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Fullerene bisadduct regioisomers containing an asymmetric diamide tether
(Oxford : Pergamon-Elsevier Science Ltd, 2017)
Four macrocyclic bis(pyrrolidino)fullerene regioisomers with e-edge, e-face, trans-4 and cis-2 addition patterns were synthesized from the corresponding monoadduct by Prato's cycloaddition in a yield of 50%, and fully ...
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 ...
Alkylation of carbonyl compounds in the TiCl4-promoted reaction of trimethylsilyl enol ethers with epoxides
(Oxford : Pergamon-Elsevier Science Ltd, 2001)
Titanium tetrachloride promoted reaction of trimethylsilyl enol ethers with ethylene oxide affords homoaldol type products in moderate/good yields. Monosubstituted epoxides react regioselectively: the nucleophilic attack ...
Photochemically induced mercuric oxide - iodine oxidation of some unsaturated steroid compounds
(Pergamon, 1994)
Photochemically induced HgO/I2 oxidation of cholest-5-en-3α-ol (6) and cholest-5-en-3β-ol (7) afforded (Scheme 3) products arising from the corresponding alkoxy radicals (12, 13 and 14a,b) and from attack of the I2O ...
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 ...
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 ...
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 ...
Unusual mode of reactivity of 2-alkylidene-4-oxothiazolidine S-oxides under the Pummerer reaction conditions
(Oxford : Pergamon-Elsevier Science Ltd, 2013)
The reactivity of 2-alkylidene-4-oxothiazolidine S-oxides under the Pummerer reaction conditions, using Ac2O, TFAA, SOCl2 and SOBr2 as initiators, has been examined. Almost all reactions proceeded with absolute regioselectivity ...
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 ...