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Transformation of steroidal 5α,8α-peroxides to the 14-membered ring containing 5,10;8,9-diseco-steroid derivatives
(Elsevier, 1985)
Thermal decomposition of steroidal 5α,8α-peroxides (such as 1) resulted in bisfragmentation of the C(5)-C(10) and C(8)-C(9) bonds, and elimination of acetic acid, to produce a new type of bicyclic compounds, namely ...
Stereoselective synthesis of (-)-cytoxazone and (+)-epi-cytoxazone
(Oxford : Pergamon-Elsevier Science Ltd, 2004)
Optically pure (-)-cytoxazone was synthesized, starting from methyl p-methoxycinnamate, in six steps and in 31%, overall yield. The required anti-aminoalcohol configuration was established by combining Sharpless asymmetric ...
Selective borane reductions of progesterone
(Elsevier, 1967)
A number of selective reductions using borane end metal borohydrides has been described. In our studies of hydroboration of steroid conjugated ketones under different conditions and with different solvents we have found ...
A new type of sesqiterpene lactone isolated from artemisia annua L. arteannuin B
(Elsevier, 1973)
The structure of a new sesquiterpene lactone, arteannuin B, isolated from Artemisia annua L. is reported.
Reactions of transition metal carbonyl anions with 2-(1-bromoalkylidene)thiazolidin-4-ones: halogenophilic attack or deprotonation
(Oxford : Pergamon-Elsevier Science Ltd, 2011)
Bromophilic attack by the transition metal carbonyl anion, [Re(CO)(5)]Na (pK(a) = 21.1), on 2-(1-bromoalkylidene)thiazolidin-4-ones is significantly faster than abstraction of an acidic lactam hydrogen (pK(a) similar to ...
The structure of glycerol acetals
(Elsevier, 1967)
It is known that the condensation of with polyols yields cyclic acetals. Thus, carbonyl compounds it is known that by condensation of benzaldehyde with glycerol, a mixture of 2-phenyl-5-hydroxy-1,3-dioxane and 2-phenyl-4 ...
Bromophilic substitution/carbophilic substitution cascade reactions of alpha,alpha-dibromo-2-methoxyacetophenone with C-, N- and O-nucleophiles
(Oxford : Pergamon-Elsevier Science Ltd, 2010)
alpha,alpha-Dibromo-2-methoxyacetophenone reacts, under mild reaction conditions, with C-, N- and O-nucleophiles via a bromophilic substitution/protonation/carbophilic substitution cascade process to afford alpha-monosub ...
Favorski type rearrangement in the lead tetraacetate oxidation of enamines promoted by boron trifluoride
(Elsevier, 1980)
Favorski type rearrangement has been achieved in the lead tetraacetate oxidation of enamines in the presence of boron trifluoride etherate and alcohol.
Alkylation of carbonyl compounds in the TiCl4-promoted reaction of trimethylsilyl enol ethers with ethylene oxide
(Oxford : Pergamon-Elsevier Science Ltd, 2000)
Titanium tetrachloride promoted reaction of trimethylsilyl enol ethers with ethylene oxide affords homoaldol type products in moderate/good yields. The reaction is believed to proceed via the titanium enolates. (C) 2000 ...
Reactions with lead tetraacetate. I. Oxidation of saturated aliphatic alcohols. Part 1
(Elsevier, 1963)
It was recently shown that various steroid alcohols could react with lead tetraacetate in non-polar solvents to give tetrahydrofuran and tetrahydropyran derivatives. cyclization occurring when the position of and the ...