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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 ...
Palladium-catalysed synthesis of allyl acetates from allenes
(Oxford : Pergamon-Elsevier Science Ltd, 2010)
Allyl acetates were synthesised from allenes utilising methodology based on the general reactivity of pi-allyl palladium intermediates which participate efficiently in transformations involving nucleophiles. Reactions of ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...