Hydrocarbons with at least one triple bond in the linear portion, of the general formula Cn-H2n-2.
Changing an open-chain hydrocarbon to a closed ring. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Rhodium. A hard and rare metal of the platinum group, atomic number 45, atomic weight 102.905, symbol Rh. (Dorland, 28th ed)
Organic chemistry methodology that mimics the modular nature of various biosynthetic processes. It uses highly reliable and selective reactions designed to "click" i.e., rapidly join small modular units together in high yield, without offensive byproducts. In combination with COMBINATORIAL CHEMISTRY TECHNIQUES, it is used for the synthesis of new compounds and combinatorial libraries.
Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
Isomeric forms and derivatives of PROPANOL (C3H7OH).
Organic or inorganic compounds that contain the -N3 group.
A chemical element having an atomic weight of 106.4, atomic number of 46, and the symbol Pd. It is a white, ductile metal resembling platinum, and following it in abundance and importance of applications. It is used in dentistry in the form of gold, silver, and copper alloys.
Alicyclic hydrocarbons in which three or more of the carbon atoms in each molecule are united in a ring structure and each of the ring carbon atoms is joined to two hydrogen atoms or alkyl groups. The simplest members are cyclopropane (C3H6), cyclobutane (C4H8), cyclohexane (C6H12), and derivatives of these such as methylcyclohexane (C6H11CH3). (From Sax, et al., Hawley's Condensed Chemical Dictionary, 11th ed)
Acyclic branched or unbranched hydrocarbons having two carbon-carbon double bonds.
A hard, brittle, grayish-white rare earth metal with an atomic symbol Ru, atomic number 44, and atomic weight 101.07. It is used as a catalyst and hardener for PLATINUM and PALLADIUM.
Synthetic organic reactions that use reactions between unsaturated molecules to form cyclical products.
The creation of an amine. It can be produced by the addition of an amino group to an organic compound or reduction of a nitro group.
Imines are organic compounds containing a functional group with a carbon-nitrogen double bond (=NH or =NR), classified as azomethines, which can be produced from aldehydes or ketones through condensation with ammonia or amines.
Saturated indolizines that are fused six and five-membered rings with a nitrogen atom at the ring fusion. They are biosynthesized in PLANTS by cyclization of a LYSINE coupled to ACETYL COENZYME A. Many of them are naturally occurring ALKALOIDS.
Vinyl compounds, in the context of medical materials, refer to synthetic polymers made from vinyl chloride or vinyl acetate monomers, which are used in the production of various medical devices and supplies such as blood bags, intravenous (IV) bags, tubing, and gloves due to their flexibility, transparency, and resistance to chemicals and heat.
A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)
Compounds similar to hydrocarbons in which a tetravalent silicon atom replaces the carbon atom. They are very reactive, ignite in air, and form useful derivatives.
Organic compounds that contain GOLD as an integral part of the molecule. Some are used as ANTIRHEUMATIC AGENTS. The term chrysotherapy derives from an ancient Greek term for gold.
Organic compounds that contain silicon as an integral part of the molecule.
A chemosterilant agent that is anticipated to be a carcinogen.
Organic compounds that contain the -NCO radical.
Compounds with two triple bonds. Some of them are CYTOTOXINS.
A technology, in which sets of reactions for solution or solid-phase synthesis, is used to create molecular libraries for analysis of compounds on a large scale.
'Ketones' are organic compounds with a specific structure, characterized by a carbonyl group (a carbon double-bonded to an oxygen atom) and two carbon atoms, formed as byproducts when the body breaks down fats for energy due to lack of glucose, often seen in diabetes and starvation states.
Ring compounds having atoms other than carbon in their nuclei. (Grant & Hackh's Chemical Dictionary, 5th ed)
A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.

Smoothing of the thermal stability of DNA duplexes by using modified nucleosides and chaotropic agents. (1/688)

The effect of alkyltrimethylammonium ions on the thermostability of natural and modified DNA duplexes has been investigated. We have shown that the use of tetramethylammonium ions TMA+along with the chemical modification of duplexes allow the fine adjustment of T m and the possibility of obtaining several duplex systems with varied isostabilizedtemperatures, some of which show greater stability than those of natural DNA. This approach could be very useful for DNA sequencing by hybridization.  (+info)

Inhibition of glutathione synthesis with propargylglycine enhances N-acetylmethionine protection and methylation in bromobenzene-treated Syrian hamsters. (2/688)

The finding that liver necrosis caused by the environmental glutathione (GSH)-depleting chemical, bromobenzene (BB) is associated with marked impairment in O- and S-methylation of BB metabolites in Syrian hamsters raises questions concerning the role of methyl deficiency in BB toxicity. N-Acetylmethionine (NAM) has proven to be an effective antidote against BB toxicity when given after liver GSH has been depleted extensively. The mechanism of protection by NAM may occur via a replacement of methyl donor and/or via an increase of GSH synthesis. If replacement of the methyl donor is an important process, then blocking the resynthesis of GSH in the methyl-repleted hamsters should not decrease NAM protection. This hypothesis was examined in this study. Propargylglycine (PPG), an irreversible inhibitor of cystathionase, was used to inhibit the utilization of NAM for GSH resynthesis. Two groups of hamsters were pretreated with an intraperitoneal (ip) dose of PPG (30 mg/kg) or saline 24 h before BB administration (800 mg/kg, ip). At 5 h after BB treatment, an ip dose of NAM (1200 mg/kg) was given. Light microscopic examinations of liver sections obtained 24 h after BB treatment indicated that NAM provided better protection (P < 0.05) in the PPG + BB + NAM group than in the BB + NAM group. Liver GSH content, however, was lower in the PPG + BB + NAM group than in the BB + NAM group. The Syrian hamster has a limited capability to N-deacetylated NAM. The substitution of NAM with methionine (Met; 450 mg/kg) resulted in a higher level of GSH in the BB + Met group than in the BB + NAM group (P < 0.05). The enhanced protection by PPG in the PPG + BB + NAM group was accompanied by higher (P < 0.05) urinary excretions of specificO- and S-methylated bromothiocatechols than in the BB + NAM group. The results suggest that NAM protection occurs primarily via a replacement of the methyl donor and that methyl deficiency occurring in response to GSH repletion plays a potential role in BB toxicity.  (+info)

Inhibition of gene expression by anti-sense C-5 propyne oligonucleotides detected by a reporter enzyme. (3/688)

Using a reporter plasmid containing the luciferase gene under the control of the insulin-like growth factor 1 (IGF-1) promoter region [including its 5' untranslated region (UTR)], we demonstrate that a 17-mer oligophosphorothioate containing C-5 propyne pyrimidines is able to inhibit luciferase gene expression in the nanomolar concentration range when the anti-sense oligonucleotide is targeted either to a coding sequence in the luciferase gene or to the 5' UTR of the gene for IGF-1. Inhibition was obtained independently of whether the plasmid and the anti-sense oligonucleotide were co-transfected or transfected separately into hepatocarcinoma cells. However, the efficiency of inhibition by the anti-sense oligonucleotides was 10-fold greater in the first case. The unmodified oligophosphorothioate targeted to the 5' UTR of IGF-1 did not inhibit luciferase gene expression at a 100-fold higher concentration unless its length was increased from 17 to 21 nt, in which case an inhibition of gene expression was obtained and an IC50 of 200 nM was observed.  (+info)

Elevated expression of liver gamma-cystathionase is required for the maintenance of lactation in rats. (4/688)

Liver gamma-cystathionase activity increases in rats during lactation; its inhibition due to propargylglycine is followed by a significant decrease in lactation. This is reversible by N-acetylcysteine administration. To study the role of liver gamma-cystathionase and the intertissue flux of glutathione during lactation, we used lactating and virgin rats fed liquid diets. Virgin rats were divided into two groups as follows: one group was fed daily a diet containing the same amount of protein that was consumed the previous day by lactating rats (high protein diet-fed rats); the other virgin group was fed the normal liquid diet (control). The expression and activity of liver gamma-cystathionase were significantly greater in lactating rats and in high protein diet-fed virgin rats compared with control rats. The total glutathione [reduced glutathione (GSH) + oxidized glutathione (GSSG)] released per gram of liver did not differ in lactating rats or in high protein diet-fed rats, but it was significantly higher in these two groups than in control virgin rats. Liver size and the GSH + GSSG released by total liver were significantly higher in lactating rats than in high protein diet-fed virgin rats, and this difference was similar to the amount of glutathione taken up by the mammary gland (454.2 +/- 36.0 nmol/min). The uptake of total glutathione by the lactating mammary gland was much higher than the uptakes of free L-cysteine and L-cystine, which were negligible. These data suggest that the intertissue flux of glutathione is an important mechanism of L-cysteine delivery to the lactating mammary gland, which lacks gamma-cystathionase activity. This emphasizes the physiologic importance of the increased expression and activity of liver gamma-cystathionase during lactation.  (+info)

Guest exchange in an encapsulation complex: a supramolecular substitution reaction. (5/688)

Encapsulation complexes are reversibly formed assemblies in which small molecule guests are completely surrounded by large molecule hosts. The assemblies are held together by weak intermolecular forces and are dynamic: they form and dissipate on time scales ranging from milliseconds to days-long enough for many interactions, even reactions, to take place within them. Little information is available on the exchange process, how guests get in and out of these complexes. Here we report that these events can be slow enough for conventional kinetic studies, and reactive intermediates can be detected. Guest exchange has much in common with familiar chemical substitution reactions, but differs in some respects: no covalent bonds are made or broken, the substrate is an assembly rather than a single molecule, and at least four molecules are involved in multiple rate-determining steps.  (+info)

Effects of a lipoxygenase inhibitor, panaxynol, on vascular contraction induced by angiotensin II. (6/688)

We investigated whether a lipoxygenase inhibitor, panaxynol, affected the vascular contraction induced by angiotensin (Ang) II and the mean arterial pressure in spontaneously hypertensive rats (SHR). Panaxynol suppressed dose-dependently the contractile responses induced by 30 nM Ang II in isolated intact and endothelial cell-denuded aorta in the hamster. IC50 values in the intact and endothelial cell-denuded aorta were 23 and 20 microM, respectively. In SHR, the mean arterial pressure after injection of 30 and 60 mg/kg panaxynol was reduced, and the maximum hypotensive values were 23 and 48 mmHg, respectively. Thus, lipoxygenase products may affect the renin-angiotensin system.  (+info)

Similarity and dissimilarity in mode and mechanism of action between YT-146, a selective adenosine receptor A2 agonist, and adenosine in isolated canine hearts. (7/688)

To elucidate the differences in mode and mechanism of action between YT-146, a highly selective adenosine A2 receptor agonist, and adenosine, we compared their effects on coronary circulation and myocardium and modifications of these effects by glibenclamide, a blocker of ATP-sensitive potassium (K) channels, in three kinds of isolated, blood-perfused canine heart preparations. YT-146 and adenosine were injected i.a. In all preparations both YT-146 and adenosine increased coronary blood flow and in this respect YT-146 was about 5 times as potent as adenosine. The increase in blood flow caused by adenosine was transient, whereas that produced by YT-146 was biphasic; the transient increase was followed by a sustained one. In isolated, blood-perfused sinoatrial (SA) node preparations, YT-146 failed to affect sinus rate, whereas adenosine reduced sinus rate by about 38% at its maximum effect. In isolated, blood-perfused atrioventricular (AV) node preparations, when injected into the artery supplying the AV node, YT-146 exerted no effect on AV conduction time, whereas adenosine prolonged AV conduction time by about 17% at the maximum effect. In isolated, blood-perfused papillary muscle preparations, the force of contraction was affected by neither YT-146 nor adenosine. In the same preparations the effect of YT-146 in increasing coronary blood flow was antagonized by glibenclamide in such a manner that the maximum increase was suppressed, but that of adenosine was not. Reactive hyperemia induced by ischemia for 30 seconds was not affected by glibenclamide. These results suggest that although both YT-146 and adenosine produce an increase in coronary blood flow via adenosine A2 receptors, the opening of ATP- or glibenclamide-sensitive K channels is involved in the action of the former, but scarcely in the action of the latter. The opening of ATP- or glibenclamide-sensitive K-channels is less likely involved in reactive hyperemia.  (+info)

NAD(+)-dependent (S)-specific secondary alcohol dehydrogenase involved in stereoinversion of 3-pentyn-2-ol catalyzed by Nocardia fusca AKU 2123. (8/688)

An NAD(+)-dependent alcohol dehydrogenase was purified to homogeneity from Nocardia fusca AKU 2123. The enzyme catalyzed (S)-specific oxidation of 3-pentyn-2-ol (PYOH), i.e., part of the stereoinversion reaction for the production of (R)-PYOH, which is a valuable chiral building block for pharmaceuticals, from the racemate. The enzyme used a broad variety of secondary alcohols including alkyl alcohols, alkenyl alcohols, acetylenic alcohols, and aromatic alcohols as substrates. The oxidation was (S)-isomer specific in every case. The K(m) and Vmax for (S)-PYOH and (S)-2-hexanol oxidation were 1.6 mM and 53 mumol/min/mg, and 0.33 mM and 130 mumol/min/mg, respectively. The enzyme also catalyzed stereoselective reduction of carbonyl compounds. (S)-2-Hexanol and ethyl (R)-4-chloro-3-hydroxybutanoate in high optical purity were produced from 2-hexanone and ethyl 4-chloro-3-oxobutanoate by the purified enzyme, respectively. The K(m) and Vmax for 2-hexanone reduction were 2.5 mM and 260 mumol/min/mg. The enzyme has a relative molecular mass of 150,000 and consists of four identical subunits. The NH2-terminal amino acid sequence of the enzyme shows similarity with those of the carbonyl reductase from Rhodococcus erythropolis and phenylacetaldehyde reductase from Corynebacterium sp.  (+info)

Alkynes are a type of hydrocarbons that contain at least one carbon-carbon triple bond in their molecular structure. The general chemical formula for alkynes is CnH2n-2, where n represents the number of carbon atoms in the molecule.

The simplest and shortest alkyne is ethyne, also known as acetylene, which has two carbon atoms and four hydrogen atoms (C2H2). Ethyne is a gas at room temperature and pressure, and it is commonly used as a fuel in welding torches.

Alkynes are unsaturated hydrocarbons, meaning that they have the potential to undergo chemical reactions that add atoms or groups of atoms to the molecule. In particular, alkynes can be converted into alkenes (hydrocarbons with a carbon-carbon double bond) through a process called partial reduction, or they can be fully reduced to alkanes (hydrocarbons with only single bonds between carbon atoms) through a process called complete reduction.

Alkynes are important intermediates in the chemical industry and are used to produce a wide range of products, including plastics, resins, fibers, and pharmaceuticals. They can be synthesized from other hydrocarbons through various chemical reactions, such as dehydrogenation, oxidative coupling, or metathesis.

Cyclization is a chemical process that involves forming a cyclic structure or ring-shaped molecule from a linear or open-chain compound. In the context of medicinal chemistry and drug design, cyclization reactions are often used to synthesize complex molecules, including drugs, by creating rings or fused ring systems within the molecule's structure.

Cyclization can occur through various mechanisms, such as intramolecular nucleophilic substitution, electrophilic addition, or radical reactions. The resulting cyclized compounds may exhibit different chemical and biological properties compared to their linear precursors, making them valuable targets for drug discovery and development.

In some cases, the cyclization process can lead to the formation of stereocenters within the molecule, which can impact its three-dimensional shape and how it interacts with biological targets. Therefore, controlling the stereochemistry during cyclization reactions is crucial in medicinal chemistry to optimize the desired biological activity.

Overall, cyclization plays a significant role in the design and synthesis of many pharmaceutical compounds, enabling the creation of complex structures that can interact specifically with biological targets for therapeutic purposes.

I'm sorry for any confusion, but "Rhodium" is not a medical term. It is a chemical element with the symbol Rh and atomic number 45. It is a rare, silvery-white, hard, corrosion-resistant, and chemically inert transition metal. It is found in small quantities in platinum or nickel ores along with some other rare metals.

It's primarily used in industrial applications, such as being a key component in catalytic converters in automobiles, which helps to reduce harmful emissions. It's also used in jewelry, electronics, and scientific instruments due to its properties of resistance to corrosion and heat.

If you have any medical terms or concepts that you would like me to explain, please let me know!

Click chemistry is a term used to describe a group of chemical reactions that are fast, high-yielding, and highly selective. These reactions typically involve the formation of covalent bonds between two molecules in a simple and efficient manner, often through the use of a catalyst. The concept of click chemistry was first introduced by K. B. Sharpless, who won the Nobel Prize in Chemistry in 2001 for his work on chiral catalysis.

In the context of medical research and drug development, click chemistry has emerged as a valuable tool for rapidly synthesizing and optimizing small molecule compounds with therapeutic potential. By using click chemistry reactions to quickly and efficiently link different chemical building blocks together, researchers can rapidly generate large libraries of potential drug candidates and then screen them for biological activity. This approach has been used to discover new drugs for a variety of diseases, including cancer, infectious diseases, and neurological disorders.

One common type of click chemistry reaction is the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, which involves the reaction between an azide and an alkyne to form a triazole ring. This reaction is highly selective and can be carried out under mild conditions, making it a popular choice for chemical synthesis in the life sciences. Other types of click chemistry reactions include the Diels-Alder cycloaddition, the thiol-ene reaction, and the Staudinger ligation.

Overall, click chemistry has had a significant impact on medical research and drug development by enabling the rapid and efficient synthesis of complex small molecule compounds with therapeutic potential. Its versatility and selectivity make it a powerful tool for researchers seeking to discover new drugs and better understand the molecular mechanisms underlying human disease.

Alkenes are unsaturated hydrocarbons that contain at least one carbon-carbon double bond in their molecular structure. The general chemical formula for alkenes is CnH2n, where n represents the number of carbon atoms in the molecule.

The double bond in alkenes can undergo various reactions, such as addition reactions, where different types of molecules can add across the double bond to form new compounds. The relative position of the double bond in the carbon chain and the presence of substituents on the carbon atoms can affect the physical and chemical properties of alkenes.

Alkenes are important industrial chemicals and are used as starting materials for the synthesis of a wide range of products, including plastics, resins, fibers, and other chemicals. They are also found in nature, occurring in some plants and animals, and can be produced by certain types of bacteria through fermentation processes.

Stereoisomerism is a type of isomerism (structural arrangement of atoms) in which molecules have the same molecular formula and sequence of bonded atoms, but differ in the three-dimensional orientation of their atoms in space. This occurs when the molecule contains asymmetric carbon atoms or other rigid structures that prevent free rotation, leading to distinct spatial arrangements of groups of atoms around a central point. Stereoisomers can have different chemical and physical properties, such as optical activity, boiling points, and reactivities, due to differences in their shape and the way they interact with other molecules.

There are two main types of stereoisomerism: enantiomers (mirror-image isomers) and diastereomers (non-mirror-image isomers). Enantiomers are pairs of stereoisomers that are mirror images of each other, but cannot be superimposed on one another. Diastereomers, on the other hand, are non-mirror-image stereoisomers that have different physical and chemical properties.

Stereoisomerism is an important concept in chemistry and biology, as it can affect the biological activity of molecules, such as drugs and natural products. For example, some enantiomers of a drug may be active, while others are inactive or even toxic. Therefore, understanding stereoisomerism is crucial for designing and synthesizing effective and safe drugs.

Molecular structure, in the context of biochemistry and molecular biology, refers to the arrangement and organization of atoms and chemical bonds within a molecule. It describes the three-dimensional layout of the constituent elements, including their spatial relationships, bond lengths, and angles. Understanding molecular structure is crucial for elucidating the functions and reactivities of biological macromolecules such as proteins, nucleic acids, lipids, and carbohydrates. Various experimental techniques, like X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and cryo-electron microscopy (cryo-EM), are employed to determine molecular structures at atomic resolution, providing valuable insights into their biological roles and potential therapeutic targets.

Catalysis is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst, which remains unchanged at the end of the reaction. A catalyst lowers the activation energy required for the reaction to occur, thereby allowing the reaction to proceed more quickly and efficiently. This can be particularly important in biological systems, where enzymes act as catalysts to speed up metabolic reactions that are essential for life.

"Propanols" is a general term that refers to a class of alcohols containing a propanol group, which is a functional group made up of a carbon atom bonded to three hydrogen atoms and a hydroxyl group (-OH). There are two primary structures for propanols: 1-propanol (n-propyl alcohol) and 2-propanol (isopropyl alcohol), which differ in the arrangement of their carbon chain.

1-Propanol, also known as n-propyl alcohol, has a linear structure with the hydroxyl group attached to one end of the carbon chain: CH3CH2CH2OH. It is a colorless liquid that is used as a solvent and in the production of other chemicals.

2-Propanol, also known as isopropyl alcohol or isopropanol, has a branched structure with the hydroxyl group attached to a branch on the second carbon atom: (CH3)2CHOH. It is a colorless, flammable liquid that is widely used as a solvent and disinfectant.

Both 1-propanol and 2-propanol have applications in various industries, including pharmaceuticals, cosmetics, and cleaning products. However, they should be handled with care due to their flammability and potential health hazards, such as irritation of the eyes, skin, and respiratory tract.

An azide is a chemical compound that contains the functional group -N=N+=N-, which consists of three nitrogen atoms joined by covalent bonds. In organic chemistry, azides are often used as reagents in various chemical reactions, such as the azide-alkyne cycloaddition (also known as the "click reaction").

In medical terminology, azides may refer to a class of drugs that contain an azido group and are used for their pharmacological effects. For example, sodium nitroprusside is a vasodilator drug that contains an azido group and is used to treat hypertensive emergencies.

However, it's worth noting that azides can also be toxic and potentially explosive under certain conditions, so they must be handled with care in laboratory settings.

I'm sorry for the confusion, but "Palladium" is not a medical term. It is a chemical element with symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. It's used in various applications, including jewelry, dental work, electronics, and chemical reactions. If you have any medical terms you would like me to define, please let me know!

Cycloparaffins, also known as naphthenes or cycloalkanes, are a type of hydrocarbon molecule that contain one or more closed rings of carbon atoms. These rings can be saturated, meaning that they contain only single bonds between the carbon atoms, and may also contain one or more alkyl substituents.

The term "cycloparaffin" is used in the context of organic chemistry and petroleum refining to describe a specific class of hydrocarbons. In medical terminology, cycloparaffins are not typically referenced directly, but they may be relevant in certain contexts, such as in discussions of industrial chemicals or environmental exposures.

Cycloparaffins can be found in various sources, including crude oil and natural gas, and they are often used as feedstocks in the production of various chemicals and materials. They are also found in some foods, such as vegetable oils and animal fats, and may be present in trace amounts in some medications or medical devices.

While cycloparaffins themselves are not typically considered to have direct medical relevance, exposure to certain types of cycloparaffins or their derivatives may be associated with various health effects, depending on the level and duration of exposure. For example, some cycloparaffin-derived chemicals have been linked to respiratory irritation, skin and eye irritation, and potential developmental toxicity. However, it is important to note that these effects are typically associated with high levels of exposure in occupational or industrial settings, rather than with normal environmental or dietary exposures.

Alkadienes are organic compounds that contain two carbon-carbon double bonds in their molecular structure. The term "alka" refers to the presence of hydrocarbons, while "diene" indicates the presence of two double bonds. These compounds can be classified as either conjugated or non-conjugated dienes based on the arrangement of the double bonds.

Conjugated dienes have their double bonds adjacent to each other, separated by a single bond, while non-conjugated dienes have at least one methylene group (-CH2-) separating the double bonds. The presence and positioning of these double bonds can significantly affect the chemical and physical properties of alkadienes, including their reactivity, stability, and spectral characteristics.

Alkadienes are important intermediates in various chemical reactions and have applications in the production of polymers, pharmaceuticals, and other industrial products. However, they can also be produced naturally by some plants and microorganisms as part of their metabolic processes.

I'm sorry for any confusion, but "Ruthenium" is not a medical term. It is a chemical element with the symbol "Ru" and atomic number 44. Ruthenium is a transition metal that belongs to the platinum group. It is typically found in ores alongside other platinum group metals and is used in various industrial applications, such as electrical contacts and wear-resistant surfaces. It does not have direct relevance to medical terminology or healthcare.

A cycloaddition reaction is a type of chemical reaction involving the formation of one or more rings through the coupling of two unsaturated molecules. This process typically involves the simultaneous formation of new sigma bonds, resulting in the creation of a cyclic structure. Cycloaddition reactions are classified based on the number of atoms involved in each component molecule and the number of sigma bonds formed during the reaction. For example, a [2+2] cycloaddition involves two unsaturated molecules, each containing two atoms involved in the reaction, resulting in the formation of a four-membered ring. These reactions play a significant role in organic synthesis and are widely used to construct complex molecular architectures in various fields, including pharmaceuticals, agrochemicals, and materials science.

Amination is a chemical process or reaction that involves the addition of an amino group (-NH2) to a molecule. This process is often used in organic chemistry to create amines, which are compounds containing a basic nitrogen atom with a lone pair of electrons.

In the context of biochemistry, amination reactions play a crucial role in the synthesis of various biological molecules, including amino acids, neurotransmitters, and nucleotides. For example, the enzyme glutamine synthetase catalyzes the amination of glutamate to form glutamine, an essential amino acid for many organisms.

It is important to note that there are different types of amination reactions, depending on the starting molecule and the specific amino group donor. The precise mechanism and reagents used in an amination reaction will depend on the particular chemical or biological context.

In the field of organic chemistry, imines are a class of compounds that contain a functional group with the general structure =CR-NR', where C=R and R' can be either alkyl or aryl groups. Imines are also commonly referred to as Schiff bases. They are formed by the condensation of an aldehyde or ketone with a primary amine, resulting in the loss of a molecule of water.

It is important to note that imines do not have a direct medical application, but they can be used as intermediates in the synthesis of various pharmaceuticals and bioactive compounds. Additionally, some imines have been found to exhibit biological activity, such as antimicrobial or anticancer properties. However, these are areas of ongoing research and development.

Indolizidines are a type of heterocyclic organic compound that contains a five-membered ring fused to a six-membered ring, with one nitrogen atom and one carbon atom common to both rings. The structure of indolizidine is similar to that of the naturally occurring alkaloids, which are found in various plants and animals and have diverse biological activities.

Indolizidines can be synthesized in the laboratory and have been studied for their potential therapeutic uses, such as anti-inflammatory, antiviral, and insecticidal properties. However, they can also have toxic effects and may interact with other drugs or chemicals in the body.

It is important to note that indolizidines are not a medical term per se, but rather a chemical classification of a specific type of organic compound.

"Vinyl compounds" is not a term used in medical definitions. It is a term used in chemistry and materials science to refer to a group of chemicals that contain carbon-based molecules with a vinyl group, which is a functional group consisting of a double bond between two carbon atoms, with one of the carbons also being bonded to a hydrogen atom (-CH2=CH-).

Vinyl compounds are used in various industrial and consumer products, including plastics, resins, adhesives, and coatings. Some vinyl compounds, such as polyvinyl chloride (PVC), have been used in medical devices and supplies, such as intravenous (IV) bags, tubing, and blood vessel catheters. However, the use of PVC and other vinyl compounds in medical applications has raised concerns about potential health risks due to the release of toxic chemicals, such as phthalates and dioxins, during manufacturing, use, and disposal. Therefore, alternative materials are being developed and used in medical devices and supplies.

Organometallic compounds are a type of chemical compound that contain at least one metal-carbon bond. This means that the metal is directly attached to carbon atom(s) from an organic molecule. These compounds can be synthesized through various methods, and they have found widespread use in industrial and medicinal applications, including catalysis, polymerization, and pharmaceuticals.

It's worth noting that while organometallic compounds contain metal-carbon bonds, not all compounds with metal-carbon bonds are considered organometallic. For example, in classical inorganic chemistry, simple salts of metal carbonyls (M(CO)n) are not typically classified as organometallic, but rather as metal carbonyl complexes. The distinction between these classes of compounds can sometimes be subtle and is a matter of ongoing debate among chemists.

Silanes are a group of chemical compounds that contain silicon and hydrogen. The general formula for silanes is Si_xH_(2x+2), where x is a positive integer. Silanes are named after their parent compound, silane (SiH4), which contains one silicon atom and four hydrogen atoms.

Silanes are colorless and highly flammable gases at room temperature. They are typically prepared by the reaction of metal silicides with acids or by the reduction of halogenated silanes. Silanes have a variety of industrial applications, including as intermediates in the production of silicon-based materials such as semiconductors and polymers.

In medical contexts, silanes are not typically used directly. However, some silane-containing compounds have been investigated for their potential therapeutic uses. For example, some organosilanes have been shown to have antimicrobial properties and may be useful as disinfectants or in the development of medical devices. Other silane-containing materials have been studied for their potential use in drug delivery systems or as imaging agents in diagnostic procedures.

It is important to note that some silanes can be hazardous if not handled properly, and they should only be used by trained professionals in a controlled environment. Exposure to silanes can cause irritation to the eyes, skin, and respiratory tract, and prolonged exposure can lead to more serious health effects.

Organogold compounds are chemical compounds that contain carbon-gold bonds, where gold is bonded directly to carbon atoms. These compounds have been synthesized and studied for their unique properties and potential applications in various fields, including medicine, catalysis, and materials science. In the medical context, organogold compounds have been explored as potential therapeutic agents, particularly in the treatment of cancer and infectious diseases. Some organogold compounds have shown promising antitumor and antibacterial activities, although their clinical use is still under investigation.

Organosilicon compounds are a class of chemical compounds that contain at least one organic group (a group of atoms composed mainly of carbon and hydrogen) bonded to a silicon atom. The organic group can be an alkyl group, aryl group, or any other group that is derived from a hydrocarbon.

The term "organosilicon" is used to describe the covalent bond between carbon and silicon atoms, which is a type of bond known as a "sigma bond." This bond is formed by the overlap of atomic orbitals between the carbon and silicon atoms. The resulting organosilicon compound can have a wide range of physical and chemical properties, depending on the nature of the organic group and the number of such groups attached to the silicon atom.

Organosilicon compounds are widely used in various industries, including electronics, coatings, adhesives, and pharmaceuticals. They are also used as intermediates in the synthesis of other chemical compounds. Some common examples of organosilicon compounds include silicones, which are polymers that contain repeating units of siloxane (Si-O-Si) bonds, and organofunctional silanes, which are used as coupling agents to improve the adhesion of materials to surfaces.

I'm sorry for any confusion, but "Hempa" is not a term commonly used in medical terminology. It's possible that there may be a typo or misunderstanding in the term you're looking for. If you're referring to "hemp," I can provide some information related to this.

Hemp is a variety of the Cannabis sativa plant species that is grown specifically for industrial purposes. It has very low concentrations of tetrahydrocannabinol (THC), the main psychoactive compound found in cannabis, making it unsuitable for use as a recreational drug. Hemp is used to produce a wide range of products, including textiles, paper, rope, biodegradable plastics, paint, insulation, biofuel, food, and animal feed.

If you meant to ask about something else or if there's more information you need regarding hemp, please let me know!

Isocyanates are a group of highly reactive chemicals that are widely used in the production of flexible and rigid foams, fibers, coatings, and adhesives. The most common isocyanates are toluene diisocyanate (TDI) and methylene diphenyl diisocyanate (MDI). Exposure to isocyanates can cause a range of health effects, including irritation of the eyes, nose, throat, and skin, as well as respiratory symptoms such as coughing, wheezing, and shortness of breath. Long-term exposure has been linked to the development of asthma and other respiratory diseases. Isocyanates are also known to be potential sensitizers, meaning that they can cause an allergic response in some individuals. It is important for workers who handle isocyanates to use appropriate personal protective equipment (PPE) and follow proper safety protocols to minimize exposure.

Diynes are organic compounds that contain two carbon-carbon triple bonds in their molecular structure. The general chemical formula for diynes is R-C≡C-C≡C-R, where R can be a hydrogen atom or any organic group. Diynes are important building blocks in organic synthesis and have been used to create complex molecules, nanomaterials, and pharmaceuticals. They are also of interest in materials science due to their unique electronic properties and potential applications in optoelectronics and photonics.

Combinatorial chemistry techniques are a group of methods used in the field of chemistry to synthesize and optimize large libraries of chemical compounds in a rapid and efficient manner. These techniques involve the systematic combination of different building blocks, or reagents, in various arrangements to generate a diverse array of molecules. This approach allows chemists to quickly explore a wide chemical space and identify potential lead compounds for drug discovery, materials science, and other applications.

There are several common combinatorial chemistry techniques, including:

1. **Split-Pool Synthesis:** In this method, a large collection of starting materials is divided into smaller groups, and each group undergoes a series of chemical reactions with different reagents. The resulting products from each group are then pooled together and redistributed for additional rounds of reactions. This process creates a vast number of unique compounds through the iterative combination of building blocks.
2. **Parallel Synthesis:** In parallel synthesis, multiple reactions are carried out simultaneously in separate reaction vessels. Each vessel contains a distinct set of starting materials and reagents, allowing for the efficient generation of a series of related compounds. This method is particularly useful when exploring structure-activity relationships (SAR) or optimizing lead compounds.
3. **Encoded Libraries:** To facilitate the rapid identification of active compounds within large libraries, encoded library techniques incorporate unique tags or barcodes into each molecule. These tags allow for the simultaneous synthesis and screening of compounds, as the identity of an active compound can be determined by decoding its corresponding tag.
4. **DNA-Encoded Libraries (DELs):** DELs are a specific type of encoded library that uses DNA molecules to encode and track chemical compounds. In this approach, each unique compound is linked to a distinct DNA sequence, enabling the rapid identification of active compounds through DNA sequencing techniques.
5. **Solid-Phase Synthesis:** This technique involves the attachment of starting materials to a solid support, such as beads or resins, allowing for the stepwise addition of reagents and building blocks. The solid support facilitates easy separation, purification, and screening of compounds, making it an ideal method for combinatorial chemistry applications.

Combinatorial chemistry techniques have revolutionized drug discovery and development by enabling the rapid synthesis, screening, and optimization of large libraries of chemical compounds. These methods continue to play a crucial role in modern medicinal chemistry and materials science research.

Ketones are organic compounds that contain a carbon atom bound to two oxygen atoms and a central carbon atom bonded to two additional carbon groups through single bonds. In the context of human physiology, ketones are primarily produced as byproducts when the body breaks down fat for energy in a process called ketosis.

Specifically, under conditions of low carbohydrate availability or prolonged fasting, the liver converts fatty acids into ketone bodies, which can then be used as an alternative fuel source for the brain and other organs. The three main types of ketones produced in the human body are acetoacetate, beta-hydroxybutyrate, and acetone.

Elevated levels of ketones in the blood, known as ketonemia, can occur in various medical conditions such as diabetes, starvation, alcoholism, and high-fat/low-carbohydrate diets. While moderate levels of ketosis are generally considered safe, severe ketosis can lead to a life-threatening condition called diabetic ketoacidosis (DKA) in people with diabetes.

Heterocyclic compounds are organic compounds that contain at least one atom within the ring structure, other than carbon, such as nitrogen, oxygen, sulfur or phosphorus. These compounds make up a large class of naturally occurring and synthetic materials, including many drugs, pigments, vitamins, and antibiotics. The presence of the heteroatom in the ring can have significant effects on the physical and chemical properties of the compound, such as its reactivity, stability, and bonding characteristics. Examples of heterocyclic compounds include pyridine, pyrimidine, and furan.

Copper is a chemical element with the symbol Cu (from Latin: *cuprum*) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. Copper is found as a free element in nature, and it is also a constituent of many minerals such as chalcopyrite and bornite.

In the human body, copper is an essential trace element that plays a role in various physiological processes, including iron metabolism, energy production, antioxidant defense, and connective tissue synthesis. Copper is found in a variety of foods, such as shellfish, nuts, seeds, whole grains, and organ meats. The recommended daily intake of copper for adults is 900 micrograms (mcg) per day.

Copper deficiency can lead to anemia, neutropenia, impaired immune function, and abnormal bone development. Copper toxicity, on the other hand, can cause nausea, vomiting, abdominal pain, diarrhea, and in severe cases, liver damage and neurological symptoms. Therefore, it is important to maintain a balanced copper intake through diet and supplements if necessary.

Alkynes form complexes with transition metals. Such complexes occur also in metal catalyzed reactions of alkynes such as alkyne ... Look up alkyne in Wiktionary, the free dictionary. Wikiquote has quotations related to Alkyne. -yne cycloalkyne Alkyne. ... Cycloaddition processes involving alkynes are often catalyzed by metals, e.g. enyne metathesis and alkyne metathesis, which ... Electrophilic alkynes are especially effective dienophiles. The "cycloadduct" derived from the addition of alkynes to 2-pyrone ...
An alkyne trimerisation is a [2+2+2] cycloaddition reaction in which three alkyne units (C≡C) react to form a benzene ring. The ... Alkyne trimerization is of no practical value, although the reaction was highly influential. The cotrimerization of alkynes and ... In terms of mechanism, the reactions begin with the formation of metal-alkyne complexes. The combination of two alkynes within ... Many variations have been developed, including cyclisation of mixtures of alkynes and alkenes as well as alkynes and nitriles. ...
... can be used in ring-closing operations and RCAM stands for ring closing alkyne metathesis. The olfactory ... Alkyne metathesis is an organic reaction that entails the redistribution of alkyne chemical bonds. The reaction requires metal ... Catalysts for alkyne metathesis "canopy catalysts" Air stable low-valent d2 rhenium alkylidyne various Schrock-based alkyne ... Ritter, S. (March 26, 2007). "Nitrile-Alkyne Cross-Metathesis". Chemical & Engineering News. Alkyne Metathesis in Organic ...
The alkyne zipper reaction is an organic reaction that involves isomerization of a non terminal alkyne into a terminal alkyne. ... essentially moving the alkyne along the alkane chain until a terminal alkyne is achieved. Once a terminal alkyne is achieved, ... 8, p. 146 "Alkyne Zipper Reaction". SynArchive. 2017. Archived from the original on December 22, 2017. Retrieved December 19, ... The conversion provides a useful approach for remote functionalization in long-chain alkynes. The reaction requires a strong ...
... es are often formed by the displacement of labile ligands by the alkyne. For example, a variety ... This kind of bonding was first implicated in complexes of the type W(CO)(R2C2)3. Because alkynes have two π bonds, alkynes can ... Metal alkyne complexes are intermediates in the semihydrogenation of alkynes to alkenes: C2R2 + H2 → cis-C2R2H2 This ... In organometallic chemistry, a transition metal alkyne complex is a coordination compound containing one or more alkyne ligands ...
The azide-alkyne Huisgen cycloaddition is a 1,3-dipolar cycloaddition between an azide and a terminal or internal alkyne to ... Unlike CuAAC in which only terminal alkynes reacted, in RuAAC both terminal and internal alkynes can participate in the ... While the copper(I)-catalyzed variant gives rise to a triazole from a terminal alkyne and an azide, formally it is not a 1,3- ... The copper (I) species generated in situ forms a pi complex with the triple bond of a terminal alkyne. In the presence of a ...
and alkynes. Phenyliodine(III) Dichloride, David W. Knight and Glen A. Russell, in Encyclopedia of Reagents for Organic ...
"Mechanistic Studies on the Reaction of Fischer Carbene Complex with Alkynes: Does the Alkyne Insertion Intermediate Form ... and alkynes. Walters graduated from Chicago in 1997 with a PhD in chemistry. She was an NIH postdoctoral fellow in Prof. Ronald ...
Ouellette, Robert J.; Rawn, J. David (2015). "Alkenes and Alkynes". Principles of Organic Chemistry. pp. 95-132. doi:10.1016/ ... being the only isomer that can reduce alkenes and alkynes to alkanes, but for a different reason: the trans isomer cannot line ...
The thiol-yne reaction (also known as alkyne hydrothiolation) is an organic reaction between a thiol and an alkyne. The ... Diphenyl disulfide reacts with alkynes to a 1,2-bis(phenylthio)ethylene. Reported alkynes are ynamides. A photoredox thiol-yne ... Yadav, J. S.; Reddy, B. V. Subba; Raju, A.; Ravindar, K.; Baishya, Gakul (2007). "Hydrothiolation of Unactivated Alkynes ... Weiss, Charles J.; Wobser, Stephen D.; Marks, Tobin J. (2009). "Organoactinide-Mediated Hydrothiolation of Terminal Alkynes ...
Also sometimes designed as ethinyl in compounds (ethinylestradiol, ethisterone (ethinyltestosterone)). See main page alkynes. ...
This reaction is used to protect alkynes: the alkyne is either converted with acetone to a 2-hydroxyprop-2-yl-alkyne or a ... A metal acetylide is formed in situ when an alkyne is treated with a strong bases such as a hydroxide or an alkoxide: HC≡CH + ... 3.0.CO;2-R. Wuts, Peter G. M.; Greene, Theodora W. (2007). "Chapter 8. Protection for the Alkynes". Greene's Protective Groups ... The Favorskii reaction is an organic chemistry reaction between an alkyne and a carbonyl group, under basic conditions. The ...
By hydration of alkynes. Such processes occur via enols and require the presence of an acid and mercury(II) sulfate (HgSO4). ... This equilibrium allows ketones to be prepared via the hydration of alkynes. C−H bonds adjacent to the carbonyl in ketones are ... Ketones containing alkene and alkyne units are often called unsaturated ketones. The most widely used member of this class of ... This reaction always produces a ketone, even with a terminal alkyne, the only exception being the hydration of acetylene, which ...
Alkyne Is an unsaturated hydrocarbon containing at least one carbon-carbon triple bond. The simplest acyclic alkynes with only ... ISBN 978-1-4058-5345-3. Alkyne. Encyclopædia Britannica Callister, W. D. "Materials Science and Engineering: An Introduction" ...
alkyne In organic chemistry, an unsaturated hydrocarbon containing at least one carbon-carbon triple bond. alloy A combination ... ISBN 978-1-4058-5345-3. Alkyne. Encyclopædia Britannica Callister, W. D. "Materials Science and Engineering: An Introduction" ...
Trimethylsilyl (TMS) protected alkynes, trimethyl germanium alkynes, and terminal alkynes can produce anti-carboalumination ... This zirconium cation can coordinate an alkene or alkyne where migratory insertion of a methyl then takes place. The resultant ... Carbometallations can be performed on alkynes and alkenes to form products with high geometric purity or enantioselectivity, ... Novel syntheses of .alpha.,.beta.-unsaturated cyclopentenones via allylzincation of alkynes". Journal of the American Chemical ...
In 1991, Utimoto reacted gold(III) (NaAuCl4) with alkynes and water. Teles identified a major drawback of this method as Au(III ... Norman, R. O. C.; Parr, W. J. E.; Thomas, C. B. (1976). "The reactions of alkynes, cyclopropanes, and benzene derivatives with ... Cationic gold(I) forms π-complexes with alkene or alkyne bonds, following the Dewar-Chatt-Duncanson model. Gold is certainly ... For instance, Hashmi reported an AuCl3-catalyzed alkyne / furan Diels-Alder reaction - a type of cycloaddition that does not ...
... salts as catalysts for reactions involving alkynes. An illustrative reaction is the hydration of terminal alkynes to produce ... Some alkynes undergo amination in the presence of gold(III) catalysts. For example, a mixture of acetonitrile and gold(III) ... In some cases where alkynes are present, phenols sometimes form (Ts is an abbreviation for tosyl): This reaction involves a ... Reetz, M. T.; Sommer, K. (2003). "Gold-Catalyzed Hydroarylation of Alkynes". European Journal of Organic Chemistry. 2003 (18): ...
Substrates for hydrozirconation are alkenes and alkynes. Terminal alkynes give vinyl complexes. Secondary reactions are ...
Similar reactions occur involving alkynes. Base is not required for electron-deficient alkenes (e.g., derivatives of ... "Nucleophilic and free-radical additions of phosphines and phosphine chalcogenides to alkenes and alkynes". Arkivoc. v (5): 12- ... acrylonitrile) and alkynes. Secondary (2°) phosphines, with the formula R2PH, are prepared analogously to the primary ...
The generation of nitrogen gas gives a vinyl carbene G, which via a 1,2-migration forms the desired alkyne H. The dimethyl ( ... A facile synthesis of alkynes". J. Org. Chem. 47 (10): 1837-1845. doi:10.1021/jo00349a007. D. G. Brown; E. J. Velthuisen; J. R ... S. Müller; B. Liepold; G. Roth & H. J. Bestmann (1996). "An Improved One-pot Procedure for the Synthesis of Alkynes from ... Reaction of Bestmann's reagent with aldehydes gives terminal alkynes often in very high yield and fewer steps than the Corey- ...
The four main categories are (1) nucleophilic attack on an alkene alkyne, or allyl ligand and (2) insertion of the alkene into ... Pohlki, F.; Doye, S. (2003). "The catalytic hydroamination of alkynes". Chem. Soc. Rev. 32 (2): 104-114. doi:10.1039/b200386b. ... Alonso, F.; Beletskaya, I.P.; Yus, M. (2004). "Transition-Metal-Catalyzed Addition of Heteroatom−Hydrogen Bonds to Alkynes". ... The unsaturated substrates that have been investigated include alkenes, dienes, alkynes, and allenes. For intramolecular ...
Other kinds of alkynes produced polymers with this treatment. With alkenes, similarly bis(difluorophosphino) is added across ... Under ultraviolet light diphosphorus tetrafluoride reacts with alkynes connected to trifluoromethyl groups to add ... "Photoreactions of tetrafluorodiphosphine with alkynes". Journal of Fluorine Chemistry. 40 (1): 41-49. doi:10.1016/S0022-1139(00 ...
Lewis, L. N.; Sy, K. G.; Bryant, G. L.; Donahue, P. E. (1991). "Platinum-catalyzed hydrosilylation of alkynes". Organometallics ...
Various aromatic alkynes can be employed to yield desired disubstituted products with satisfactory yields. Aliphatic alkynes ... It is suggested that the presence of a base results in the formation of a π-alkyne complex E. This increases the acidity of the ... It employs a palladium catalyst as well as copper co-catalyst to form a carbon-carbon bond between a terminal alkyne and an ... Copper(I) salts, such as CuI, react with the terminal alkyne and produce a copper(I) acetylide, which acts as an activated ...
It also can silylate terminal alkynes. The triflate derivative (Me3C)Me2SiOTf is used similarly but is more reactive. Bret E. ...
The typical Pd-based catalyst is tetrakis(triphenylphosphine)palladium(0). The typical unsaturated substrates are alkynes. The ...
R. J. Rahaim & J. T. Shaw (2008). "Zinc-Catalyzed Silylation of Terminal Alkynes". J. Org. Chem. 73 (7): 2912-2915. doi:10.1021 ... "Silylation of 1-alkynes with chlorosilanes promoted by Zn(OTf)2: an efficient way to the preparation of alkynylsilanes". ...
It is a terminal alkyne. A colorless liquid, 1-decyne is used as a model substrate when evaluating methodology in organic ... Ishiyama, Tatsuo; Matsuda, Nobuo; Miyaura, Norio; Suzuki, Akira (1993). "Platinum(0)-Catalyzed Diboration of Alkynes". Journal ... of Azides and Terminal Alkynes". Angewandte Chemie International Edition. 41 (14): 2596-2599. doi:10.1002/1521-3773(20020715)41 ...
The reaction with the electron-poor alkyne (C6F5)CC(C6F5) required rather harsh reaction conditions (110 °C, 7 days) and the ... In that study, 2 was reacted with three differently substituted alkynes that greatly differed in their electronic properties, ... towards alkynes in great detail. Of particular relevance was the question of whether the enhanced Lewis acidity of 2 compared 1 ... The potent Lewis acidity of 12 revealed a novel reaction pathway whereby the alkyne first adds to the borole nucleophilically, ...
Alkynes form complexes with transition metals. Such complexes occur also in metal catalyzed reactions of alkynes such as alkyne ... Look up alkyne in Wiktionary, the free dictionary. Wikiquote has quotations related to Alkyne. -yne cycloalkyne Alkyne. ... Cycloaddition processes involving alkynes are often catalyzed by metals, e.g. enyne metathesis and alkyne metathesis, which ... Electrophilic alkynes are especially effective dienophiles. The "cycloadduct" derived from the addition of alkynes to 2-pyrone ...
Alkyne agarose is a 6% crosslinked agarose resin that is activated with terminal alkyne functional groups for covalent ... Activation level 10-20 µmol alkyne groups per mL resin Bead size Spherical, 50-150 µm Support 6% Cross-linked agarose ... crosslinked agarose resin that is activated with terminal alkyne functional groups for covalent capturing azide-tagged ... Alkyne agarose is a 6% crosslinked agarose resin that is activated with terminal alkyne functional groups for covalent ...
What is the name of this Alkyne? CH3CH2C=C (Note: the above = symbol should be 3. ... An alkyne has a carbon-carbon triple bond in it. Thats all there is to it. b. If an alkyne is progressively hydrogenated by an ... Methane is a good example of a complex alkyne hydrocarbon. . Methane (CH4) is the simplest alkane, not an alkyne. Answer is D. ... Cyclic Alkyne reaction with KMnO4 and O3. Since the molecule contains both alkene and alkyne functional groups, you should ...
Adding Aryl Iodides to Alkynes. Author: ChemistryViews.org. Alkenyl halides are useful synthetic intermediates with a C=C ... The team used a range of aryl iodides and substituted alkynes as substrates, Ni(cod)2 as a catalyst (cod = 1,5-cyclooctadiene ... This radical adds to the alkynes triple bond, recombines with the nickel iodide complex, and the final product is released via ... One approach for their synthesis is the insertion of an alkyne into the carbon-halogen bond of an organohalogen compound, ...
Room temperature palladium catalysed coupling of acyl chlorides with terminal alkynes. Download Prime PubMed App to iPhone, ... Room temperature palladium catalysed coupling of acyl chlorides with terminal alkynes.. Chem Commun (Camb). 2005 Feb 28CC ... Room Temperature Palladium Catalysed Coupling of Acyl Chlorides With Terminal Alkynes. Chem Commun (Camb). 2005 Feb 28;(8)1037- ... Room temperature palladium catalysed coupling of acyl chlorides with terminal alkynes. Chem Commun (Camb). 2005. ...
Torregrosa, R. R. P., Ariyarathna, Y., Chattopadhyay, K., & Tunge, J. A. (2010). Decarboxylative Benzylations of Alkynes and ... For example, Buchwald reported the cross-coupling of benzyl halides with alkynes using stoichiometric Cs2CO3; unfortunately, ... the basic reaction conditions often induce isomerization of the product benzylic alkynes to isomeric allenes.2 Negishi reported ...
Alkenes are double bonded hydrocarbons and alkynes are triple bonded hydrocarbons. Like all hydrocarbons, they are composed ... Were going to use pre- the suffix y-n-e, yne, which is the same thing as you can [IB] is alkynes have y-n-e, so if you have ... Alkenes and alkynes are unsaturated bonds that contain one or more double or triple bonds (e.g., ethene, propene, butene, etc ... Well alkenes and alkynes are unsaturated meaning that they do not have the maximum amount of hydrogen that can, that it can ...
In addition, the proposed mechanism indicates usefulness of this concept for both internal and terminal alkynes, eliminates the ... and revealing thermodynamic aspects allowing higher yields for alkynes with para-electron-donating groups. ... In other words, the scan of the N-I∙∙∙Calkyne(1) coordinate with NIS, or either of the Si-N1∙∙∙Calkyne(1) or Si-N=N=N3∙∙∙C ... Reaction on Terminal Alkynes with NIS and TMSN3 in Acetonitrile. According to experiments [22], terminal alkynes give nitriles ...
The curious relative rates in stepwise addition of HCl or HBr to alkynes show that halogen substituents are both electron ... Chapter 5. Stepwise Addition to Alkynes - Competing Influences of Halogen [00:43:16]. Now lets look at the influence of ... CHEM 125b - Lecture 11 - Carbocations and the Mechanism of Electrophilic Addition to Alkenes and Alkynes. Chapter 1. Alkene ... Carbocations and the Mechanism of Electrophilic Addition to Alkenes and Alkynes. Overview. Substitution stabilizes alkenes, and ...
The initially disordered 1-decaboranethiolate changed into ordered (√3×√3)R 30° lattices on Au{111} typical of alkyne SAMs, ... Formation of Highly Ordered Terminal Alkyne Self-Assembled Monolayers on the Au{111} Surface through Substitution of 1- ...
AgN3-Catalyzed Hydroazidation of Terminal Alkynes and Mechanistic Studies. Z. Liu, P. Liao, X. Bi, Org. Lett., 2014, 16, 3668- ... General Silver-Catalyzed Hydroazidation of Terminal Alkynes by Combining TMS-N3 and H2O: Synthesis of Vinyl Azides. Zhenhua Liu ... A general silver-catalyzed hydroazidation of unactivated terminal alkynes with trimethylsilyl azide in the presence of water ...
Migratory Insertion reaction with alkynes tutorial of Introduction to Organometallic Chemistry course by Prof A.G. Samuelson of ... Alkynes η2 bonding - Metal dihydrogen and hydrides - Migratory Insertion reaction with alkynes - ηm (m=4 dienes and m=2n, ...
Regioselective Reductive Hydration of Alkynes To Form Branched or Linear Alcohols. L. Li, S. B. Herzon, J. Am. Chem. Soc., 2012 ... hydration of the alkyne, and hydrogenation of the intermediate aldehyde. A wide array of terminal alkynes are efficiently ... Synthesis of 1,3-Amino Alcohols, 1,3-Diols, Amines, and Carboxylic Acids from Terminal Alkynes ... Anti-Markovnikov Reductive Hydration of Terminal Alkynes. Mingshuo Zeng, Le Li and Seth B. Herzon*. *Department of Chemistry, ...
Recent number of edits (within past 90 days ...
Alkenes and alkynes:. The melting points and boiling points of alkenes and alkynes increase with an increase in molecular ... Alkenes and alkynes generally have physical properties similar to those of alkanes. ... what is the effect of melting point and boiling point on branching in alkanes , alkenes and alkynes? ...
Which of the following combinations describe the triple bond in an alkyne group? [A] The triple bond consists of two 𝜎 bonds ... Alkyne molecules contain a carbon-carbon triple bond functional group called an alkyne group. R and R dash can be an alkyl ... Alkynes are a series of organic compounds, all with the same general formula C𝑛H2𝑛−2, where 𝑛 is a nonfractional number such as ... Question Video: Describing the Bond Types of the Three Bonds in a Triple Bond in an Alkyne Group Chemistry Start Practising ...
Bifunctional 8-Arm PEG reagents have two functional groups biotin and alkyne at specific ratio of 1:7, 2:6, 4:4 , 6:2, 7:1. The ... Bifunctional 8-Arm PEG reagents have two functional groups biotin and alkyne at specific ratio of 1:7, 2:6, 4:4 , 6:2, 7:1. The ... Home / Products / PEG Products / / 8-Arm PEG-Biotin(1)/Alkyne(7), MW 20k ... biotin and alkyne functionality groups are quantitated using spectroscopic techniques and colorimetric assays. ...
... , ChemInform, June 2010, Wiley, DOI: 10.1002/chin.199911324. You ...
... Ans: Hint: A lower pH indicates that the solution is more acidic, ... Hence, alkynes are more acidic than alkanes and alkenes.. Note:. The most commonly used alkyne in industry is acetylene, which ... An alkyne is an unsaturated hydrocarbon with at least one carbon-carbon triple bond in organic chemistry. A homologous sequence ... The alkynes are more electronegative due to the presence of more character. Hydrogen atoms can therefore be liberated as ...
Applicated in medical research, drug-release, nanotechnology and new materials research, cell culture. In the study of ligand, polypeptide synthesis support, a graft polymer compounds, new materials, and polyethylene glycol-modified functional coatings and other aspects of the active compound. ...
Alkynes - Quiz - Alkynes - Chapter 3 - Alkynes , Organic Chemistry 2. Chemistry Coach ... C ≡ C bond of alkynes:. 1 σ bond ⇒ formed from 2 sp orbitals of carbon atoms. 2 π bonds ⇒ formed from 4 p orbitals of carbon ... How many distinct alkynes are there with a molecular formula of C4H6? ... nBuLi (pKa ~ 50) = MeMgBr (pKa ~ 50) , Alkynes (pKa = 25) , MeONa (pKa = 15-16) ...
01) Draw an example of each of the four types of hydrocarbons: alkane, alkene, and alkyne. (02) Answer True or False for the ...
We are providing something unique, useful and most importantly fun. By giving students a tool to find instant solutions to their doubts, were trying to make every student self-sufficient in practicing & completing their homework. ...
The sample is a polymerized alkyne; the paramagnetism arises from free radicals trapped in the polymer structure. An ... The sample is a polymerized alkyne; the paramagnetism arises from free radicals trapped in the polymer structure. An ... "Dynamic polarization in polymerized alkynes." (1964) Masters Thesis, Rice University. https://hdl.handle.net/1911/90347. ...
Biotin alkyne // Biotin propargylamide // N-Propargylbiotinamide // (+)-Biotin propargyl amide ...
The alkyne proton is acidic enough to react with the dissolving metal to give the anion, giving the metal alkynide as it shown ... According to my book terminal alkynes are not observed in Birch reduction.Why is this so? The only property I know about them ... Hema Anyway, I am looking for a textbook with the mention that terminal alkynes are not suited for Birch reduction; would you ...
Connelly, NG 1992, Organometallic electrochemistry of metal alkyne and related complexes. in AJL Pombiero & JA McCleverty (eds ... 1992). Organometallic electrochemistry of metal alkyne and related complexes. In AJL. Pombiero, & JA. McCleverty (Eds.), ... Organometallic electrochemistry of metal alkyne and related complexes. In Pombiero AJL, McCleverty JA, editors, Molecular ... Organometallic electrochemistry of metal alkyne and related complexes. / Connelly, NG. Molecular electrochemistry of inorganic ...
Learn while having fun by playing the Alkens alkynes matching game ...
  • Like other hydrocarbons, alkynes are generally hydrophobic. (wikipedia.org)
  • That's why most hydrocarbons are gaseous and however, the difference between alkenes and alkynes versus alkanes, is that they're much more reactive. (brightstorm.com)
  • 01) Draw an example of each of the four types of hydrocarbons: alkane, alkene, and alkyne. (mithilanchalgroup.com)
  • Alkynes or Acetylene Acyclic unsaturated hydrocarbons containing a carbon-carbon triple bond are called alkynes or acetylenes. (org.in)
  • Bifunctional 8-Arm PEG reagents have two functional groups biotin and alkyne at specific ratio of 1:7, 2:6, 4:4 , 6:2, 7:1. (creativepegworks.com)
  • Alkenes and alkynes are unsaturated bonds that contain one or more double or triple bonds (e.g., ethene, propene, butene, etc.) and have different chemical compounds and properties. (brightstorm.com)
  • Alkenes and alkynes are much more reactive than alkanes. (brightstorm.com)
  • So we're going to talk about alkenes and alkynes. (brightstorm.com)
  • Well alkenes and alkynes are unsaturated meaning that they do not have the maximum amount of hydrogen that can, that it can have around carbon. (brightstorm.com)
  • We're going to use pre- the suffix y-n-e, yne, which is the same thing as you can [IB] is alkynes have y-n-e, so if you have two carbons of ethyne, three carbons of propyne, four carbons of butyne and then again when you get to betyne you're start dealing with the same issue that you had in alkenes, and betenes. (brightstorm.com)
  • So what are some properties of alkenes and alkynes? (brightstorm.com)
  • what is the effect of melting point and boiling point on branching in alkanes , alkenes and alkynes? (topperlearning.com)
  • The melting points and boiling points of alkenes and alkynes increase with an increase in molecular weight. (topperlearning.com)
  • Alkenes and alkynes generally have physical properties similar to those of alkanes. (topperlearning.com)
  • Why are alkenes and alkynes called unsaturated compounds? (socratic.org)
  • Alkenes and alkynes are called unsaturated compounds because the carbon atoms that they contain are bonded to fewer hydrogen atoms than they can possibly hold. (socratic.org)
  • Alkenes and alkynes are called unsaturated compounds because the carbon atoms do not have as many hydrogen atoms as they possibly could. (socratic.org)
  • Alkenes such as but-2-ene (CH₃-CH=CH-CH₃) and alkynes such as but-2-yne, (CH₃-C≡C-CH₃) are unsaturated because the middle carbons contain fewer hydrogen atoms than they possibly could. (socratic.org)
  • the so-called, " carbocation pathway " that includes addition of HX and H 3 O+ and explore how many of the reactions of alkenes we're familiar with can also be used with alkynes . (esterlium.net)
  • The number of hydrogens is, therefore, 5.A hydrocarbon with no double or triple bonds is called an a. alkane b. alkene c. alkyne d. aromatic hydrocarbon Please see the attached file. (brainmass.com)
  • In the event there is a functional group of higher priority, the alkene or alkyne should be written after the root of the name . (brainmass.com)
  • 44185 IR Tables to distinguish between 1-butyne, 2-butyne, and 2-butene Use IR tables to locate absorption bands of the stretching frequencies of the alkyne C - H bond, the alkyne C - (triple bond)- C , and the alkene C - H bond. (brainmass.com)
  • Since the molecule contains both alkene and alkyne functional groups, you should expect oxidative cleavage of both alkene and alkyne groups when subject the molecule in acidic solution of permanganate (KMnO4/H3O+). (brainmass.com)
  • And because they have they contain double if they're an alkene or triple bonds if they are an alkyne in the parent carbon chain. (brightstorm.com)
  • The definition of alkene or alkyne meaning it, that it has a double or triple bond within it. (brightstorm.com)
  • So the smallest amount of carbons that an alkene or alkyne can contain, is two. (brightstorm.com)
  • Alkyne agarose is a 6% crosslinked agarose resin that is activated with terminal alkyne functional groups for covalent capturing azide-tagged biomolecules. (vectorlabs.com)
  • Methyltetrazine-PEG4-Alkyne is a heterobifunctional reagent, activated with terminal alkyne and methyltetrazine groups connected through a PEG4 spacer. (crbdiscovery.com)
  • Methyltetrazine-PEG4-Alkyne is a heterobifunctional azide-to-TCO crosslinker with terminal alkyne and methyltetrazine groups connected through a PEG4 spacer. (crbdiscovery.com)
  • Takuya Kurahashi, Seijiro Matsubara, and colleagues, Kyoto University, Japan, have developed an intermolecular, nickel-catalyzed reaction of alkynes with aryl iodides that gives alkenyl iodides (pictured). (chemistryviews.org)
  • the reaction is tolerant of a wide variety of acyl chlorides and terminal alkynes and provides a convenient one-pot route to acetylenic ketones. (unboundmedicine.com)
  • unfortunately, the basic reaction conditions often induce isomerization of the product benzylic alkynes to isomeric allenes.2 Negishi reported the benzylic cross-coupling with acetylides via stoichiometric alkynyl zinc bromides that must be prepared from ZnBr2.3 Not only do these methods require stoichiometric bases or organometallics, but they also utilize benzyl halides that are expensive, hazardous, and more difficult to handle than related benzyl alcohol derivatives. (ku.edu)
  • Reaction profiles agree with several experimental observations, offering evidence for the formation of molecular I 2 , interpreting the necessity to increase the temperature to finalize the reaction, and revealing thermodynamic aspects allowing higher yields for alkynes with para-electron-donating groups. (mdpi.com)
  • there is considerable evidence to suggest that this reaction in fact proceeds not through a carbocation intermediate, but through a "termolecular" reaction incorporating two equivalents of H-X and the alkyne . (esterlium.net)
  • Through these improvements the method became more synthetically practical and increased the reaction substrate scope to include unreactive azides and alkynes. (fsu.edu)
  • This compound, a white solid, has been characterized by Terminal alkynes, like acetylene itself, are mildly acidic, with pKa values of around 25. (wikipedia.org)
  • The acidic hydrogen on terminal alkynes can be replaced by a variety of groups resulting in halo-, silyl-, and alkoxoalkynes. (wikipedia.org)
  • Why is ammonia less acidic than terminal alkynes? (stackexchange.com)
  • The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series with the general chemical formula CnH2n−2. (wikipedia.org)
  • A homologous sequence is formed by the simplest acyclic alkynes, which have only one triple bond and no other functional groups. (vedantu.com)
  • This dissertation describes the development of alternative products from the copper-catalyzed azide-alkyne cycloaddition (CuAAC). (fsu.edu)
  • Chapter 5 summarizes the work conducted on modifying the conditions applied to the copper catalyzed azide alkyne cycloaddition (CuAAC). (fsu.edu)
  • The title compound, C12H11N5.2H2O, which crystallizes as a dihydrate, was obtained by Cu(I)-catalysed azide-alkyne cyclo-addition from 2-azido-1-methyl-imidazole and phenyl-ethyne. (who.int)
  • atop \displaystyle {H}}{C}}}}{\ce {-H}}} 1-Butyne In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon-carbon triple bond. (wikipedia.org)
  • An alkyne is an unsaturated hydrocarbon with at least one carbon-carbon triple bond in organic chemistry. (vedantu.com)
  • The biotin and alkyne functionality groups are quantitated using spectroscopic techniques and colorimetric assays. (creativepegworks.com)
  • Disulfide Biotin alkyne is an azide-activated cleavable biotin probe that allows for efficient recovery of avidin-bound protein complexes in affinity-based assays. (broadpharm.com)
  • This reagent contains a biotin moiety linked to an alkyne group through a spacer arm containing a cleavable disulfide linker. (broadpharm.com)
  • 6-ROX alkyne is an excellent azide-reactive fluorescent reagent for labeling alkyne-containing biological molecules through click chemitry. (addexbio.com)
  • Hydrozirconation of an alkyne with the Schwartz reagent forms a vinyl zirconium intermediate, which directly undergoes a copper-catalyzed electrophilic enamidation with dioxazolones. (elsevierpure.com)
  • Alkynes are traditionally known as acetylenes, although the name acetylene also refers specifically to C2H2, known formally as ethyne using IUPAC nomenclature. (wikipedia.org)
  • Structure of Triple bond Ethyne is the first member of alkynes series. (org.in)
  • Methane (CH4) is the simplest alkane, not an alkyne . (brainmass.com)
  • The most commonly used alkyne in industry is acetylene, which is used as a fuel and a precursor to other compounds such as acrylates. (vedantu.com)
  • Write an equation for the synthesis of 2-hexanone by a. oxidation of an alcohol b. hydration of an alkyne 4. (brainmass.com)
  • An air-stable half-sandwich ruthenium complex is a highly active catalyst for the anti-Markovnikov reductive hydration of alkynes, involving the decarboxylation of formic acid, hydration of the alkyne, and hydrogenation of the intermediate aldehyde. (organic-chemistry.org)
  • In course of the past 8 years, we have developed a wide range of rhodium-catalyzed, branched-selective allylation reactions starting from either alkynes or the isomeric allenes, both terminal and internal. (uni-freiburg.de)
  • The team used a range of aryl iodides and substituted alkynes as substrates, Ni(cod) 2 as a catalyst (cod = 1,5-cyclooctadiene), 4,4′-di- tert -butyl-2,2′-dipyridyl (dtbdp) as a ligand, and toluene as solvent. (chemistryviews.org)
  • Nevertheless, a large potential has not been touched so far, with many more pronucleophiles, internal alkyne and allene substrates and applications in total synthesis possible. (uni-freiburg.de)
  • The carbanions generated by deprotonation of terminal alkynes are called acetylides. (wikipedia.org)
  • Alkynes are a series of organic compounds, all with the same general formula C𝑛H2𝑛−2, where 𝑛 is a nonfractional number such as one, two, three, and so on. (nagwa.com)
  • The second chapter describes a method for the preparation of 5-iodo-1,2,3-triazoles directly from organic azides and terminal alkynes. (fsu.edu)
  • The method described in Chapter 3 is a simple and rapid process for the synthesis of bistriazoles from organic azides and terminal alkynes under oxidative conditions ( oxygen atmosphere) with a broad substrate scope. (fsu.edu)
  • Why can't terminal alkynes take part in Birch reduction? (stackexchange.com)
  • According to my book terminal alkynes are not observed in Birch reduction.Why is this so? (stackexchange.com)
  • The methodological enhancements of the procedure described in Chapter 2 provides high conversion as well as high iodo/protio selectivity through the reduction in equivalents of alkyne, and employment of [Tri(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (TBTA). (fsu.edu)
  • : 628 Those containing triple bonds are called alkyne . (wikipedia.org)
  • Methane is a good example of a complex alkyne hydrocarbon. (brainmass.com)
  • Internal alkynes feature carbon substituents on each acetylenic carbon. (wikipedia.org)
  • Alkynes having four or more carbon atoms can form different structural isomers by having the triple bond in different positions or having some of the carbon atoms be substituents rather than part of the parent chain. (wikipedia.org)
  • The curious relative rates in stepwise addition of HCl or HBr to alkynes show that halogen substituents are both electron withdrawing and electron donating. (yale.edu)
  • Since carbocations are stabilized to a greater extent by electron releasing alkyl substituents than by hydrogen, the new carbocation will form at the end of the alkyne bearing the carbon substituent. (esterlium.net)
  • The initially disordered 1-decaboranethiolate changed into ordered (√3×√3) R 30° lattices on Au{111} typical of alkyne SAMs, indicating the complete substitution of 1-decaboranethiolate moieties, as determined by nanoscale imaging with scanning tunneling microscopy and X-ray photoelectron spectroscopy. (acs.org)
  • Nowadays, the growing maturity of this particular field of research makes hydro- functionalizations of alkynes and allenes a worthy, atom-economic alternative to previously established methods such as allylic substitution or oxidation reactions. (uni-freiburg.de)
  • Draw the simpler alkyne and alkyl bromide that could be combined to give the alkyne shown: (see image attached). (brainmass.com)
  • A wide array of terminal alkynes are efficiently processed to linear alcohols using as little as 2 mol % of catalyst at ambient temperature. (organic-chemistry.org)
  • In systematic chemical nomenclature, alkynes are named with the Greek prefix system without any additional letters. (wikipedia.org)
  • Alkyne molecules contain a carbon-carbon triple bond functional group called an alkyne group. (nagwa.com)
  • Which of the alkyne addition reactions below involves an enol intermediate? (chemistry.coach)
  • As mentioned above, the reactions of alkynes with HBr and HI (as well as HF, just in case you're curious) follow the exact same pathway. (esterlium.net)
  • We can also get this product if we simply add two equivalents of H-Cl to the starting alkyne . (esterlium.net)
  • A copper-catalyzed electrophilic enamidation starting from alkynes is reported. (elsevierpure.com)
  • One approach for their synthesis is the insertion of an alkyne into the carbon-halogen bond of an organohalogen compound, catalyzed by transition-metal complexes. (chemistryviews.org)
  • High functional group tolerance of hydrozirconation enables the use of functionalized alkynes including esters. (elsevierpure.com)
  • Terminal alkynes have the formula RC2H. (wikipedia.org)
  • How many distinct alkynes are there with a molecular formula of C 4 H 6 ? (chemistry.coach)
  • The first step is protonation of the alkyne with H-Cl in such a manner as to give the most stable carbocation intermediate. (esterlium.net)
  • In the language of valence bond theory, the carbon atoms in an alkyne bond are sp hybridized: they each have two unhybridized p orbitals and two sp hybrid orbitals. (wikipedia.org)
  • The two carbon atoms at a triple alkyne bond each have two 2p orbitals, one in the 𝑦-plane and one in 𝑧-plane. (nagwa.com)
  • Which of the following combinations describe the triple bond in an alkyne group? (nagwa.com)