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Free-radical oxidative transformations of androst-4-ene-3β,9α,17β-triol 3,17-diacetate
(Tetrahedron, 1988)
The oxidation of androst-4-ene-3β,9α,17β-triol 3,17-diacetate (2) with lead tetraacetate resulted mainly In β-fragmentation of the C(9)-C(10) bond to give a mixture of 10α- and 10β-acetoxy-Δ4-unsaturated 9,10-seco-steroidal ...
Acid-catalyzed rearrangement of some steroidal isoxazolidines
(Elsevier, 1999)
Acid-catalyzed reaction of the steroidal Δ 1 -unsaturated 3β,5β- epoxyimino compound 2 and Δ 3 -unsaturated 1β,5β-epoxyimino products 3 and 7, results in intramolecular rearrangement involving the N-CH 3 group to give the ...
The conformational equilibrium of 1,3-dichloro-5-methylcyclohexane
(Elsevier, 1981)
Two of the stereoisomers of the title compound were prepared and their dipole moments were measured. For the r-1,c-3-dichloro-t-5-methylcyclohexane, the free energy difference between conformers with axial-axial (aa) and ...
Design, synthesis, and characterization of fullerene-peptide-steroid covalent hybrids
(Oxford : Pergamon-Elsevier Science Ltd, 2014)
The present study reports the synthesis, spectral characterization, self-assembly properties, and preliminary in vitro study of antioxidant capacity of two triple covalent hybrids consisting of fullerene C-60, peptide, and ...
5,10:13,14-Disecosteroids: novel modified steroids containing 10- and 9-membered rings
(Oxford : Pergamon-Elsevier Science Ltd, 2009)
In this paper a synthetic pathway to the modified 5,10:13,14-bisfragmentation cholestane derivatives 8-14 is described. The synthesis involves introduction of the 5α- and 14α-hydroxyl groups in the cholestane molecule and ...
Oxidative 10-membered ring expansion and contraction of stereoisomeric 1(10)-unsaturated and 1,10-epoxy-5-oxo-5,10-secosteroids induced by peracids
(Oxford : Pergamon-Elsevier Science Ltd, 2012)
The present study is concerned with the oxidative behaviour of unsaturated and epoxy 5-oxo-5,10-secosteroids in the presence of m-CPBA or TFAA-UHP as oxidants in order to investigate potential parameters controlling the ...
Reaction of silyl ketene acetals with epoxides: a new method for the synthesis of gamma-butanolides
(Oxford : Pergamon-Elsevier Science Ltd, 2004)
Titanium tetrachloride promoted reaction of silyl ketene acetals with epoxides, followed by acidic work-up, affords butanolides in moderate/good yields. With epihalohydrins the reaction is regioselective and occurs at the ...
Steroid template associated peptides: design, synthesis and 2D NMR characterization of a novel protected 18-Phe,19-Gly-containing steroidal compound
(Oxford : Pergamon-Elsevier Science Ltd, 2007)
We report herein the synthesis of a novel modified steroid with two rigidly positioned amino acids in C- and N-protected forms (Gly-OtBu and N-Fmoc-l-Phe) at the angular positions (C-18 methylamino group and C-19 carboxylic ...
Catalytic oxidations of enolizable ketones using 2-alkylidene-4- oxothiazolidine vinyl bromide
(Oxford : Pergamon-Elsevier Science Ltd, 2011)
Direct oxidation of enolizable ketones to α-hydroxy derivatives, vicinal dicarbonyls or tricarbonyl compounds has been achieved by a catalytic amount of 2-alkylidene-4-oxothiazolidine vinyl bromide in DMSO as a solvent. ...
Structure, configuration, conformation and quantification of the push pull-effect of 2-alkylidene-4-thiazolidinones and 2-alkylidene-4,5-fused bicyclic thiazolidine derivatives
(Oxford : Pergamon-Elsevier Science Ltd, 2010)
Structures of a series of push-pull 2-alkylidene-4-thiazolidinones and 2-alkylidene-4,5-fused bicyclic thiazolidine derivatives were optimized at the B3LYP/6-31G(d) level of theory in the gas phase and discussed with respect ...