Similar cyclization. Medical search. Frequent questions

We carried out the DFT calculation of intramolecular cyclization reaction of α-sulfenyl-, α-sulfinyl-, α-sulfonyl-5-(R)-5-hexenyl radicals and 2,5-hexadienyl radicals by density functional theory. (ntnu.edu.tw)
Similar results were obtained for the substituents at the C6 position, and the activation energies for the intramolecular cyclization were decreased by 0.2 - 4.8 kcal/mol and the reaction rate increased from 2 to 2800 times. (ntnu.edu.tw)
In general, the reaction of 1,3-diketones and hydroxylamine affords isoxazoles through intramolecular cyclization followed by dehydration of isolable monoxime intermediates. (tracks-movie.com)
It attaches to the isonitrile group, producing the imidoyl radical, which then undergoes intramolecular cyclization, ultimately leading to the formation of 6-(difluoromethyl)phenanthridine. (thenewshacker.com)

We discover one dominant mutation is sufficient to activate cyclization, and together with two additional residues comprise a network of strongly epistatic interactions that activate, suppress or reactivate cyclization. (sri.com)
But further tests revealed that it was pa r t of a network of three residues that together interact to activate, suppress or reactivate cyclisation. (chemistryworld.com)

The preparation of the trans olefinic cyclisation precursor was investigated and metal facilitated carbonylation was used to generate a requisite aldehydic intermediate. (ucl.ac.uk)
A similar disconnection was applied to the dehydrogeosmin system and optically pure ketals of butan-2,3-diol used in lithium perchlorate solution to generate a precursor in 70% enantiomeric excess. (ucl.ac.uk)
The tripeptides were then coupled using triphosgene/collidine, giving a precursor for the cyclization step. (chemistryviews.org)
ketoimine linear precursor undergoes spontaneous cyclization to precolibactin 886 on HPLC purification. (omicsdi.org)

The Nazarov cyclization reaction (often referred to as simply the Nazarov cyclization) is a chemical reaction used in organic chemistry for the synthesis of cyclopentenones. (wikipedia.org)
As the reaction has been developed, variants involving substrates other than divinyl ketones and promoters other than Lewis acids have been subsumed under the name Nazarov cyclization provided that they follow a similar mechanistic pathway. (wikipedia.org)
The mechanism of the classical Nazarov cyclization reaction was first demonstrated experimentally by Charles Shoppee to be an intramolecular electrocyclization and is outlined below. (wikipedia.org)
In this way, the Nazarov cyclization is a rare example of a stereoselective pericyclic reaction, whereas most electrocyclizations are stereospecific. (wikipedia.org)
Research involving the reaction was relatively quiet in subsequent years, until in the mid-1980s when several syntheses employing the Nazarov cyclization were published. (wikipedia.org)
A similar reaction between the 2-hydroxyethylamine and the aziridinium ion does not take place at pH 7.4. (aspetjournals.org)
A study of the Hajos-Parrish reaction - an amino acid catalysed intramolecular cyclisation - was undertaken to evaluate the effects of solvent and amino acid choice on enantioselectivity. (ucl.ac.uk)
The cyclization reaction of the dimethylamides 2b, 5, 6 and 7, resulting from the reaction of mandelic acid with the aminoazirine 1, yields the 6-, 9-, 12- and 15-membered cyclic depsipeptides 10 - 13, respectively. (uzh.ch)
Finally, combined quantum mechanical/molecular mechanical (QM/MM) modelling of the IdmH reaction shows that the active site of the enzyme provides an appropriate environment to promote indane-ring formation, supporting the assignment of IdmH as the key Diels-Alderase catalysing the final step in the biosynthesis of indanomycin through a similar mechanism to other recently characterized Diels-Alderases involved in polyketide-tailoring reactions. (iucr.org)
Studies showed that Calicheamicin binds to the DNA in the minor groove, and then they undergo a reaction similar to Bergman's cyclization to generate diradical substances. (bocsci.com)

On-line HPLC-ion spray mass spectrometry was more practical and useful than conventional HPLC alone for characterizing the products of these cyclization reactions. (elsevierpure.com)

The success of the Nazarov cyclization as a tool in organic synthesis stems from the utility and ubiquity of cyclopentenones as both motifs in natural products (including jasmone, the aflatoxins, and a subclass of prostaglandins) and as useful synthetic intermediates for total synthesis. (wikipedia.org)
Recently, significant advances have taken place in the use of SmI 2 for the synthesis of nitrogen heterocycles, enabled in large part by the unique combination of high reducing power of this reagent (E 1/2 of up to −2.8 V) with excellent chemoselectivity of the reductive umpolung cyclizations mediated by SmI 2 . (mdpi.com)
We have recently shown this in the stereoselective total synthesis of the antiviral sesquiterpene (+)-schisanwilsonene by a cyclization/1,5-acetoxy migration/intermolecular cyclopropanation. (unboundmedicine.com)
In this synthesis, the cyclization/1,5-acetoxy migration is faster than the alternative 1,2-acyloxy migration that would result in racemization. (unboundmedicine.com)
It has been successfully utilized in the synthesis of peptides, particularly in peptide cyclization and modifications. (genengnews.com)
The similar reductive-cyclisation of the oxime of ethyl alpha-2-acetylcyclo-hexyl phenylacetate was also investigated, and the method was extended in a modified form to the synthesis of 1-benzyldecahydroisoquinoline. (gla.ac.uk)
After various challenges, a short and facile formal total synthesis relying on a cascade cyclization was developed. (jyu.fi)

Cyclization washighly regioselective, givinga41mixtureof[48]anditsregioisomer. (forex-consultant.com)

The emergence of terpene cyclization was critical to the evolutionary expansion of chemical diversity yet remains unexplored. (sri.com)
Here we report the first discovery of an epistatic network of residues that controls the onset of terpene cyclization in Artemisia annua. (sri.com)

alpha-2-AcetyIcyclohexylphenyl- acetonitrile, prepared by the Michael condensation of 1-acetylcyclohex-1-ene and phenylacetonitrile, underwent reductive-cyclisation when hydrogenated in alcohol solution over copper chromite catalyst to yield two stereoisomeric N-alkyl-4-phenyl-1-methyldecahydroisoquinolines, the nature of the N-alkyl group depending on the alcohol used as solvent. (gla.ac.uk)
Muons accompanying electrons, called muoniums, preferentially added to the carbon atom of the isonitrile unit, forming an intermediate that subsequently underwent a cyclization process. (thenewshacker.com)

When this 'gateway' mutation was transferred to wild-type BFS, it was enough to generate cyclisation. (chemistryworld.com)
Click chemistry is a term introduced by Professors Valery V. Fokin and Nobel laureate K.B. Sharpless to describe chemistry tailored to generate substances quickly and reliably by joining small units together similar to the modular strategy adopted by Mother Nature. (genengnews.com)

We have also developed stereospecific syn-additions, which probably occur through similar intermediates. (unboundmedicine.com)
Sathyamoorthi, Shyam We have developed a highly stereospecific cyclization of aziridine silanols into 1′-amino-tetrahydrofurans. (ku.edu)

They also select for dithiol type redox proteins, like Trx, based on kinetic reversibility and offer fast cyclization due to the preorganization by annelation (JACS 2021). (uni-muenchen.de)

Remarkably, this epistatic network of equivalent residues also controls cyclization in a BFS homologue from Citrus junos. (sri.com)
The team started with amorpha-4,11-diene synthase (ADS) and (E)-ß-farnesene synthase (BFS), a pair of enzymes from the plant which are structurally very similar - 49% of the amino acid residues are the same. (chemistryworld.com)
They reasoned that the important parts of the enzyme enabling cyclisation would lie within the active site or nearby, and thus focused their attention on the residues within 6Å of this region. (chemistryworld.com)

While literature syntheses of 1′-amino-tetrahydrofurans exist, only one example, contemporaneous with our work, uses a similar cyclization for their construction. (ku.edu)

Cyclization stabilizes the peptide molecule by locking its conformation, thus increasing potency and in vivo half-life. (genengnews.com)
on-resin cyclization of peptide ligands of the vascular endothelial growth factor receptor 1, etc. (genengnews.com)
Cyclisation is an optional modification, to aid in the constrained conformation of a peptide with a disulphide bond. (nridigital.com)
Peptide byproducts could be identified from the series of multiply charged ions observed, even when some of these peptides eluted from the HPLC with similar retention times. (elsevierpure.com)
In addition to the desired cyclic peptide, the peptide byproducts observed following the cyclization using BOP (benzotriazol-1-yl-oxy- tris(dimethylamino)phosphonium hexafluorophosphate) were the linear peptide, the cyclic dimeric peptide and the linear peptide resulting from aspartimide rearrangement. (elsevierpure.com)

Several MO caging strategies have been devised, employing hairpin structures, 7 intermolecular duplexes, 8 , 9 nucleobase modifications, 10 or oligonucleotide cyclization. (cdc.gov)

Similarly, β-substitution directed inward restricts the s-trans conformation so severely that E-Z isomerization has been shown to occur in advance of cyclization on a wide range of substrates, yielding the trans cyclopentenone regardless of initial configuration. (wikipedia.org)
Then again, cyclization gave trans furan 11 in acceptable yield. (organicchemistry.eu)

This radical served as the starting point for the isonitrile insertion and cyclization processes within the isonitrile group. (thenewshacker.com)

This versatility allows similar peptides to function in different ways and, in some cases, lead to complete inhibition. (nridigital.com)
We offer head-to-tail cyclisation, side-chain cyclisation, stapled, and other constrained peptides. (nridigital.com)

The major prior art in this field has applied cyclic 5-membered disulfides (1,2 dithiolanes) as substrates for TrxR in a similar way to create such tools. (uni-muenchen.de)

Differential scanning calorimetry demonstrates that the [Cu(PyED) 2 ](NO 3 ) 2 ( 11 ) exhibits a Bergman cyclization temperature (156 °C) which is dramatically reduced from that of the corresponding [Cu(PyED) 2 ](PF 6 ) ( 19 ) analogue (326 °C), indicating that large differences in the reactivities of these metalloenediynes can be accessed by variations in metal oxidation state. (figshare.com)
The distorted, 4-coordinate dichloride compound Cu(PyED)(Cl) 2 ( 15 ) exhibits a cyclization temperature (265 °C) between those of 11 and 19 , suggesting that variation in geometry of the copper center is responsible for the wide range of reactivities. (figshare.com)
An evaluation of the antibacterial activities of the products showed that the synthetic pargamicin A exhibits similar potency to the natural product, but the diastereomer did not (pictured, MIC = minimum inhibitory concentration). (chemistryviews.org)
Ustat A exhibits potent anti-tumor activity (GI₅₀ = 15.5 nM) and its biological mechanism varies from other structurally similar scaffolds. (sdsu.edu)

The cyclization of a linear dynorphin A (Dyn A) analogue to give the lactam derivative cyclo[D-Asp 2 ,Dap 5 ]Dyn A(1-13)NH 2 (where Dap = α,β-diaminopropionic acid) was studied to evaluate the usefulness of different coupling reagents for side chain to side chain lactam formation. (elsevierpure.com)
NMR, however, can help distinguish subtle chemical differences, such as C5 side-chain alterations, cyclization, or substitutions of a carboxylic acid and hydroxyl (OH) group. (terpenesandtesting.com)

To circumvent legal restrictions, semi-synthetic derivatives of CBD are now frequently added to cannabis products, producing 'high' effects similar to those induced by Δ9-THC. (wendyjanehhc.com)
The first semi-synthetic cannabinoid to appear in the EU was obtained through cyclization and hydrogenation of CBD, and is known as hexahydrocannabinol (HHC). (wendyjanehhc.com)

A novel strategy to construct the dehydrogeosmin skeleton was designed, employing a 'biomimetic' intramolecular polyene cyclisation as the key step. (ucl.ac.uk)
In own of their key step, they were using a Mukaiyama type cyclization. (organicchemistry.eu)

markers (theta(pC) = 0.042) was small and similar to that based EPZ-6438 chemical structure on the five nuclear microsatellite markers (theta(p) = 0.054). (inhibitorlibrary.com)

Find Similar Structures. (tracks-movie.com)
Because cannabinoids have very similar structures, some instrumental methods will be hard-pressed to differentiate them. (terpenesandtesting.com)

Though cyclizations following the general template above had been observed prior to Nazarov's involvement, it was his study of the rearrangements of allyl vinyl ketones that marked the first major examination of this process. (wikipedia.org)

Molecular mechanics/dynamics calculations reveal that the geometries of these metal centers force the alkyne termini to a wide range of distances (3.85−4.20 Å), thereby accounting for the variability in Bergman cyclization temperatures. (figshare.com)

This graph shows the total number of publications written about "Cyclization" by people in this website by year, and whether "Cyclization" was a major or minor topic of these publications. (rush.edu)

As originally described, the Nazarov cyclization involves the activation of a divinyl ketone using a stoichiometric Lewis acid or protic acid promoter. (wikipedia.org)

Eastern fragment 3 should be synthesized from 6 using similar cyclization conditions. (organicchemistry.eu)
Using the same conditions as before, cyclization gave the desired furan which was transformed into the unsaturated ester 16 by metathesis. (organicchemistry.eu)

Showing items with similar title or keywords. (jyu.fi)

They directed a beam of positive muons (subatomic particles similar to protons but nine times lighter) towards the isonitrile group and carefully observed the changes in their spins. (thenewshacker.com)

In NHPs, 16-BrSalA caused dose-dependent increases in the neuroendocrine biomarker prolactin, similar to other KOR agonists, at doses without robust sedative effects. (ku.edu)

Similar results are obtained for the benzoenediyne and quinoline analogues. (figshare.com)

sativum), leeks (A. The code would be similar to location pathMyWebSite overrideModeAllow system. (forex-consultant.com)

Organisms4

Chemicals and Drugs44

Analytical, Diagnostic and Therapeutic Techniques and Equipment7

Phenomena and Processes12

Disciplines and Occupations1

Technology, Industry, Agriculture3

Information Science1

Intramolecular cyclization4

Suppress or reactivate2

Precursor4

Reaction10

Reactions1

Synthesis7

Regioselective1

Terpene2

Underwent2

Generate2

Stereospecific2

20211

Residues3

Syntheses1

Peptide5

Intermolecular1

Trans2

Processes1

Peptides2

Substrates1

Exhibits4

Side-chain2

Synthetic2

Step2

Chemical1

Structures2

General1

Wide range1

Total1

Activation1

Conditions2

Keywords1

Times1

Effects1

Results1

System1