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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; ...
Criteria for the determination of the stereochemistry of steroidal indolizidines
(Elsevier, 1974)
E/F-Indolizidine steroids, which represent a structural unit of Solanum alkaloids, have been synthesized and used to evaluate criteria (IR—Bohlmann bands,1a-c —hydrogenbond,2a-e NMR,3a-c mass spectra,4 kinetic studies of ...
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 ...
Lead tetra-acetate oxidation of saturated aliphatic alcohols-V. Factors influencing the formation of cyclic ethers and carbonyl compounds
(Elsevier, 1966)
Factors influencing the relative rates of the homolytic and heterolytic processes in the lead tetra-acetate oxidation of unbranched primary and secondary aliphatic alcohols have been investigated, with a view to determine ...
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 ...
The reaction of lead tetra-acetate with some acyclic hydroxy-ethers
(Elsevier, 1966)
By means of lead tetra-acetate in refluxing benzene open-chain 1,2-, 1,3-, 1,4- and 1,5-hydroxy-ethers are mainly converted to the corresponding five-membered or six-membered cylic products. Thus, 2-alkoxy-1-ethanols afford ...
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 ...