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Oxidative hydrolysis and acid-catalyzed rearrangement of steroidal isoxazolidines
(Elsevier, 1991)
Treatment of steroidal isoxazolidines 3a, 3b and 5b with N-methylhydroxylamine hydrochloride in boiling ethanol-pyridine (1:1) solution results in elimination of the CH3NH2fragment, affording products of oxidative hydrolysis ...
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 ...
Acetoxylation of steroidal lactones by means of lead tetraacetate
(Elsevier, 1970)
One of the structural features of many bitter principles ls the presence of a &-lactone ring. Some of these compounds differ from one another by the state of oxidation of the molecule as a whole and also by the state of ...
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 ...
Novel trioxygenated caryophyllenes from Inula Spiraefolia
(Pergamon Press, 1982)
The identification of two novel isomeric trioxygenated caryophyllenes from the plant species Inula Spiraefolia is reported. © 1982.
Reactions of ortho-substituted α,α-dibromoacetophenones with nucleophiles: first examples of combined carbophilic and bromophilic attack on C-Br bonds
(Oxford : Pergamon-Elsevier Science Ltd, 2009)
An efficient method for the formation of α-carbonyl-monosubstituted acetophenones from ortho-methoxy- and ortho-hydroxy-α,α-dibromoacetophenones and a range of selected nucleophiles, occurring via a carbophilic ...
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 ...
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.
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 ...
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.