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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 ...
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 ...
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 ...
Preparation and photolysis of 2-diazo-6-oximino- and 2,6-bisdiazo-4-tert. Butylcyclohexanone
(Elsevier, 1967)
Reaction mechanism of diazoketone photolysie is assumed
to involve the formation ofd-keto-carbene intermediates, final products being dependent on the molecular structure and
reaction medium. Numerous example8 of ...
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 ...
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 ...
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.
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.