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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 ...
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 ...
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 ...
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.
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 ...
On the choice of optimal conformation in linear free-energy relationships. Reactivity of 2-[(carboxymethyl)sulfanyl]-4-oxo-4-arylbutanoic acids with diphenyldiazomethane
(Amsterdam : Elsevier, 2012)
Rate constants for the esterification of eleven 2-[(carboxymethyl)sulfanyl]-4-oxo-4-arylbutanoic acids
with diphenyldiazomethane in ethanol at 30 C were determined, and correlated with substituent constants
using classical ...
A novel tandem process leading to functionalized glutarimides
(Oxford : Pergamon-Elsevier Science Ltd, 2005)
The synthesis of various functionalized or spirobicyclic glutarimides by a novel tandem process has been disclosed. The reaction involves a base-catalyzed Michael addition of active methylene compounds to secondary conjugated ...
Annulations of isoquinoline and beta-carboline ring systems: synthesis of 8-oxoprotoberberine derivatives
(Oxford : Pergamon-Elsevier Science Ltd, 2011)
Annulation processes of isoquinoline and p-carboline compounds have been investigated leading to synthetic routes for the preparation of 8-oxoprotoberberine derivatives. The key steps combined a diene formation/Diels-Alder ...
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 ...
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 ...