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Non-sensitized photooxygenation of some steroidal isoxazolidines
(Pergamon press, 1991)
UV irradiation of the steroidal isoxazolidines 2a, 2b, and 2c in various solvents in the presence of molecular oxygen, results in oxidative cleavage of the epoxyimino bridge to give several products; the N-unsubstituted ...
Circular dichroism of some cyclopropane ring containing 1,3-cyclo-5,10-seco-steroidal ketones
(Elsevier, 1982)
Circular dichroism of the rearranged keto steroids 3 and 4, containing a condensed three and nine-membered ring system, shows that the conformation of the nine-membered ring is the same in solution as in the crystal; ...
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 ...
Organocatalyzed Tsuji-Trost reaction: a new method for the closure of five- and six-membered rings
(Oxford : Pergamon-Elsevier Science Ltd, 2009)
A combination of organotransition metal catalysis and organocatalysis allows for Tsuji-Trost 5-exo- and 6-exo-cyclizations of aldehydes. This transformation can also be accomplished as a catalytic asymmetric reaction, which ...
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 ...
Synthesis and properties of bis(pyrrolidino)fullerenes bridged by a flexible alkyl-tether
(Oxford : Pergamon-Elsevier Science Ltd, 2015)
The one-pot bistycloaddition of alkyl-tethered diglycines to C-60 provided five series of bridged bis(pyrrolidino)fullerenes with good regioselectivity, giving mainly cis-2 and cis-3 products. An influence of the bridge ...
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 ...
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 ...