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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 ...
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.
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 ...
The conversion of unbranched primary alkyl and arylalkyl amines to nitriles by means of lead tetraacetate
(Elsevier, 1965)
The only amino compounds oxidized so far with lead tetroacetate were primary aromatic amines, which gave mainly the corresponding azo compounds(1), and some tertiary aryldialkyl amines, which in glacial acetic acid in the ...
Synthesis, biological evaluation, and modeling of a C,D-seco-taxoid
(Oxford : Pergamon-Elsevier Science Ltd, 2005)
A C,D-seco-paclitaxel derivative 12 was prepared and tested for biological activity. The key step in the synthesis was a free radical fragmentation of the bicyclic tertiary alcohol 7 under the conditions of the hypobromite ...
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 ...
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 ...
An improved preparation of 3-α-acetoxy-11,20-diketo-(5β)-pregnane, the key intermediate in the synthesis of 11-oxygenated corticosteroids
(Elsevier, 1967)
Although microbiological methods of introducing oxygen at C-11 of the steroid molecule are effective, it is obvious that purely synthetic way of producing cortisone and its analogs from bile acids or hecogenin have never ...
X-ray and carbon-13 nuclear magnetic resonance characterization of cyclopropane derivatives obtained by solvolysis of (E)-3α- and (E)-3β-hydroxy-5,10-seco-1(10)-cholesten-5-one tosylates
(Pergamon Press, 1979)
The stereochemistries and conformations of the cyclopropane ring containing compounds derived from (E-3α- and (E)-3β-hydroxy-5,10-seco-1(10)-cholesten-5-one tosylates have been determined by X-ray methods and the results ...