• simplest
  • The simplest spiro compounds are bicyclic (having just two rings), or have a bicyclic portion as part of the larger ring system, in either case with the two rings connected through the defining single common atom. (wikipedia.org)
  • third, the substiuents of the rings of the spiro compound may be such that the only reason they are chiral arises solely from the twist of their rings, e.g., in the simplest bicyclic case, where two structurally identical rings are attached via their spiro atom, resulting in a twisted presentation of the two rings. (wikipedia.org)
  • It is the simplest spiro-connected cycloalkane, a triangulane. (wikipedia.org)
  • SC-5233 (6,7-dihydrocanrenone), the C17α propanoic acid lactone of testosterone (androst-4-en-17β-ol-3-one), is the unsubstituted parent or prototype compound of the spirolactones, and is one of a few of the simplest members of the series along with SC-8109 (the 19-demethyl analogue of SC-5233) and canrenone (the 1,2-didehydro analogue of SC-5233). (wikipedia.org)
  • The simplest spiro-connected cycloalkene, it is very unstable-decomposing even below −100 °C-due to its high bond strain and does not occur in nature. (wikipedia.org)
  • synthesis
  • citation needed] In both cases, the presence of the spiro center, often with four distinct groups attached, and with its unique aspects of chirality, adds unique challenges to the chemical synthesis of each compound type. (wikipedia.org)
  • A rapid synthesis of title compounds under solvent free conditions using MWI is described. (niscair.res.in)
  • This invention relates to tetralin derivatives useful in medicine for the treatment of hypertension, to the synthesis of the compounds, to the pharmaceutical. (patents.com)
  • A simple and efficient method for the synthesis of spiro[indoline-3,9′-xanthene]trione derivatives by means of condensation between isatins and 1,3-cyclohexanedione in the presence of a catalytic amount of magnesium perchlorate at 80 °C in 50% aqueous ethanol medium has been described. (mdpi.com)
  • One-Step Synthesis and Structure of an Oligo(spiro-orthocarbonate), J. Am. Chem. (wikipedia.org)
  • Elusive bowtie pinned down - synthesis of spiropentadiene, a carbonaceous compound nicknamed bowtiediene because it is shaped like a bowtie, Science News, July 13, 1991. (wikipedia.org)
  • cyclohexane
  • From the reaction of a monoprotected cyclohexane-1,4-dione 5 with the allylic hydroperoxide 6 derived from the singlet oxygenation of methyl hydroxytiglate, one monospiro compound was obtained, the 1,2,4-trioxane ketone 7, as well as a mixture of the diastereoisomeric syn- and anti bis-1,2,4-trioxanes 8. (mdpi.com)
  • isomeric
  • Hence, in the third case, the lack of planarity described above gives rise to what is termed axial chirality in otherwise identical isomeric pair of spiro compounds, because they differ only in the right- versus left-handed "twist" of structurally identical rings (as seen in allenes, sterically hindered biaryls, and alkylidenecycloalkanes as well). (wikipedia.org)
  • nitrogen
  • In one study, a [4.5.5.enestrane was synthesized with one carbon atom replaced by nitrogen because aza- compounds and their salts are more likely to form crystalline compounds suitable for X-ray analysis than low-molecular-weight alkanes. (wikipedia.org)
  • novel
  • Spiro compounds are present throughout the natural world, some cases of which have been exploited to provide tool compounds for biomedical study and to serve as scaffolds for the design of therapeutic agents with novel shapes. (wikipedia.org)
  • Novel diol spiro orthocarbonates derived from glycerol as anti-shrinkage additives for the cationic photopolymerization of epoxy monomers, Polymer International, 59(5), 680-685 (2010), doi:10.1002/pi.2755. (wikipedia.org)
  • steroids
  • Spirolactones, also known as steroid-17α-spirolactones, 17α-spirolactosteroids, or simply 17α-spirolactones, are a group of steroids which are both spiro compounds and lactones and which feature these two structural properties combined in the form of a spirolactone ring at the C17α position. (wikipedia.org)
  • solvent
  • Tetraethoxymethane can be used as a solvent and for the alkylation of CH-acidic compounds (e.g. phenols and carboxylic acids). (wikipedia.org)
  • reactions
  • Reactions of O -peracylated C -(1-bromo-β- d -glucopyranosyl)formamides with thioamides furnished the corresponding glucopyranosylidene-spiro-thiazolin-4-one. (mdpi.com)
  • These compounds undergo intramolecularWittig reactions in boiling benzene to produce highly strained spirocyclobutenederivatives, which spontaneously undergo ring-opening reactions to produce dialkyl (E)-2-[1-(2-oxocyclopentyliden)ethyl]-2-butenedioates. (mdpi.com)
  • Spiropentadiene was synthesised from bistrimethylsilylpropynone 1 by reaction with p-toluenesulfonylhydrazide to tosylhydrazone 2 followed by treatment with sodium cyanoborohydride to allene 3 and followed by two successive reactions with chlorocarbene generated from methyllithium and dichloromethane to spiro compound 5. (wikipedia.org)
  • compositions
  • Present invention is a non-toxic, flavor stable, pleasant tasting composition releasing Zn.sup.2+ from compositions containing a highly ionizable zinc compound. (patents.com)
  • decades
  • During the past two decades, several glucopyranosylidene-spiro heterocycles have emerged as potent inhibitors of glycogen phosphorylase (GP) [ 1 , 2 , 3 , 4 , 5 ]. (mdpi.com)
  • Therefore
  • Therefore, fused bicyclic compounds have a "0" included in the brackets. (wikipedia.org)
  • Therefore, this compound is of interest for study: by finding which groups cause the tumor-promoting activity, and removing them, the new compound will only have an anti-proliferation activity, and can be used as a therapy for cancer. (wikipedia.org)
  • crystallography
  • For the strong binding of compounds A to the enzyme, X-ray crystallography of the enzyme-inhibitor complexes revealed the importance of the H-bond donor β-NH, as well as that of the α-carbonyl groups highlighted in red [ 23 , 24 ]. (mdpi.com)
  • chemical
  • Tetraethoxymethane is a chemical compound which is formally formed by complete ethylation of the hypothetical orthocarbonic acid C(OH)4 (orthocarboxylic acid violates the Erlenmeyer rule and is unstable in free state). (wikipedia.org)
  • TNP refers to the chemical compound 2,4,6-trinitrophenol, also known as Picric acid. (wikipedia.org)
  • present
  • citation needed] As well, the spiro motif is present in various practical compound types (such as dyes), as well as in a wide variety of oligo- and polymeric materials designs, for the unique shapes and properties the spiro center imparts, e.g., in the design of electronically active materials in particular. (wikipedia.org)
  • The present invention provides methods of treating or preventing autoimmune diseases with spiro 2,4-pyrimidinediamine compounds, as well as methods of treating, preventing or ameliorating symptoms associated with such diseases. (patentsencyclopedia.com)
  • The present invention relates to oxocarbon-, pseudooxocarbon- and radialene compounds as well as to their use as doping agent for doping an organic semiconductive matrix material, as blocker material, as charge injection layer, as electrode material as well as organic semiconductor, as well as electronic. (google.es)
  • method
  • Europäische Patentschrift EP 0881212 B1, Production method of aminobenzene compound, Erfinder: H. Hashimoto et al. (wikipedia.org)
  • active
  • A new anti-inflammatory active flavanone glycoside 5,7-dihydroxy-8,4 -dimethoxyflavanone-5-O-a-l-rhamno -pyranosyl-7-O-b-d-arabinopyranosyl-(1 4 )-O-b-d-glucopyranoside A along with a known compound dihydroquercetin-4 ' -methyl ether B have been isolated from the leaves of Echinops echinatus . (niscair.res.in)
  • Both compounds were active as GPIs in the low micromolar concentration range. (mdpi.com)
  • This compounds are active in the cleavage of the RNA model compound HPNP. (wikipedia.org)
  • structure
  • The structure and stereochemistry of the new compounds were established by means of NMR and electronic circular dichroism (ECD) data supported by time-dependent density functional theory ECD (TDDFT-ECD) calculations. (mdpi.com)
  • certain
  • Fenspiride (INN, brand names Eurespal, Pneumorel and others) is an oxazolidinone spiro compound used as a drug in the treatment of certain respiratory diseases. (wikipedia.org)
  • often
  • citation needed] The 2-3 rings being joined are most often different in nature, though they, on occasion, be identical [e.g., spiro[5.ndecane, just shown, and spirapentadiene, at right]. (wikipedia.org)
  • The spiroketal fragments are often important for the biological activity of the compounds containing them. (mdpi.com)