22072-19-1Relevant academic research and scientific papers
Conformational Analysis. 46. Conformational Equilibria in 3-Hydroxy-, 3-Methoxy-, and 3-Acetoxythianes, Their Sulfoxides and Sulfones, and Some Corresponding 3-Methyl Homologues
Brunet, Ernesto,Eliel, Ernest L.
, p. 677 - 686 (1986)
Conformational equilibria have been measured, by low-temperature carbon-13 and proton NMR spectroscopy, for 3-hydroxythiane, its two epimeric sulfoxides, and the corresponding sulfone and their methyl ethers and acetates, as well as the corresponding derivatives of 3-methyl-3-hydroxythiane and their acetates.Of particular note are large solvent and concentration effects on the conformational free energies, ΔG0ae, especially in cases where intramolecular and intermolecular hydrogen bonding are competitive.Thus, in 3-hydroxythiane, ΔG0 rises from -1.20 kcal/mol in 4 M CD2Cl2 to -0.22 kcal/mol in 0.0011 M CD2Cl2; for the corresponding cis sulfoxide the rise is from +1.3 kcal/mol in 0.0023 M CD2Cl2 and in the sulfone it is from -1.3 kcal/mol in 0.3 M CD3COCD3 to -0.9 kcal/mol in 0.3 M CD2Cl2 to -0.16 kcal/mol in 0.002 M CD2Cl2.
Synthesis of Novel Cyclic Sulfone Dihydropyridines Facilitated by a Selective Ethyl Diazoacetate Ring Expansion
Dodd, John H.,Schwender, Charles F.,Gray-Nunez, Yolanda
, p. 1453 - 1456 (2007/10/02)
A series of novel cyclic sulfone dihydropyridines with five to nine membered rings have been synthesized.Anomalous intermediates isolated from the Hantzch condensation were found to vary depending on the sulfone ring size and aromatic substitution.Tin tetrachloride has been shown to be a superior Lewis acid catalyst for ethyl diazoacetate ring expansion of the requisite β-keto cyclic sulfone precursors.
PHARMACEUTICALLY USEFUL SUBSTITUTED THIACYCLOALKENO [3,2-B]PYRIDINES, COMPOSITIONS AND METHOD OF USE
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, (2008/06/13)
Novel substituted thiacycloalkeno [3,2-b]pyridines are described. These compounds are useful as calcium channel antagonists with cardiovascular, antiasthmatic and antibronchoconstrictor activity.
Enzymes in organic syntheses. 19. Evaluation of the stereoselectivities of horse liver alcohol dehydrogenase; catalyzed oxidoreductions of hydroxy- and ketothiolanes, -thianes, and -thiepanes
Jones, J. Bryan,Schwartz, Harold M.
, p. 1574 - 1579 (2007/10/02)
The specificity of horse liver alcohol dehydrogenase (HLADH) with respect to unsubstituted five-, six-, and seven-membered ring 3- and 4-thiaketone and -thiaalcohol substrates has been examined.The enzyme is found to have a broad tolerance of the structural variations within this series.HLADH also exhibits encouraging (up to 46percent) enantiotopic and enantiomeric specifity in preparative-scale reduction and oxidation reactions of the heterocyclic ketones and alcohols respectively.
