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Structure-reactivity relationship in the solvolysis of 5,10-secosteroidal 5-p-nitrobenzoates
(Pergamon Press, 1979)
The solvolysis of (Z)- and (E)-3β-acyloxy-5,10-seco-1(10)-cholesten-5β-ol p-nitrobenzoates 4 and 5 has been investigated and compared with the solvolytic reactivity of the epimeric (Z)- and (E)-5α-p-nitrobenzoates 1 and ...
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; ...
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 ...
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 ...
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 ...
2-Alkylidene-4-oxothiazolidine S-oxides: synthesis and stereochemistry
(Oxford : Pergamon-Elsevier Science Ltd, 2013)
A series of 5-unsubstituted and 5-substituted 2-alkylidene-4-oxothiazolidine-S-oxides were synthesized by the sulfur-oxidation with m-CPBA. The stereochemistry of 5-substituted sulfoxides was determined by means of NMR ...
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 ...
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 ...