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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 ...
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 ...
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 ...
A highly regioselective, protecting group controlled, synthesis of bicyclic compounds via Pd-catalysed intramolecular cyclisations
(Oxford : Pergamon-Elsevier Science Ltd, 2013)
Intramolecular Pd-catalysed cyclisation reactions for the preparation of bicyclic compounds have been studied as a model system towards the synthesis of corialstonine and corialstonidine. Significant differences in reactivity ...
Study of the intramolecular Heck reaction: synthesis of the bicyclic core of corialstonidine
(Oxford : Pergamon-Elsevier Science Ltd, 2015)
The intramolecular Heck reaction has been examined for the preparation of the core bicyclic structure of corialstonidine. Initial attempts to cyclise a vinyl iodide moiety onto a cyclic allyl alcohol were complicated by ...
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 ...
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 ...
Titanium tetrachloride promoted reaction of silyl ketene acetals with epoxides: a new method for the synthesis of gamma-butanolides
(Oxford : Pergamon-Elsevier Science Ltd, 2002)
A new method for the synthesis of gamma-butanolides is described. The titanium tetrachloride promoted reaction of silyl ketene acetals with epoxides, followed by acidic work-up, affords the corresponding butyrolactones in ...
Magnetic criteria of aromaticity in a benzene cation and anion: how does the Jahn-Teller effect influence the aromaticity?
(Oxford : Pergamon-Elsevier Science Ltd, 2012)
The aromatic/antiaromatic behavior of the Jahn-Teller UT) active benzene cation and anion has been investigated using Density Functional Theory (DFT) calculations of Nuclear Independent Chemical Shifts (NICS) and magnetic ...
Linear free energy relationships of half-wave reduction potentials of (E)-4-aryl-4-oxo-2-butenoic acids
(Elsevier, 2010)
Half-wave reduction potentials of a set of twelve (E)-4-aryl-4-oxo-2-butenoic acids obtained by direct current polarography in methanol are reported. E1/2 is correlated with Hammett sigma values as well as with values of ...