Roussel Uclaf

Hoechst Marion Roussel

Christian Richard

Jean-Yves Godard

Philippe Mackiewicz

Jean Buendia

Denis Prat

Francis Brion

A process for the preparation of a compound of the formula ##STR1## wherein R.sub.1 is selected from the group consisting of hydrogen and alkyl of 1 to 8 carbon atoms, R.sub.2 and R.sub.4 are alkyl of 1 to 4 carbon atoms and R.sub.3 is alkyl of 1 to 8 carbon atoms comprising reacting a compound of the formula ##STR2## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are defined as above or an amine salt thereof with an electrophilic halogenating agent to obtain a compound of the formula ##STR3## wherein Hal.sub.1 is halogen, reacting the latter with a halohydroxylating agent to obtain a compound of the formula ##STR4## wherein Hal.sub.2 is halogen, reacting the latter with a base to obtain a compound of the formula ##STR5## reacting the latter with a diastereoselective reducing agent to obtain a compound of the formula ##STR6## reacting the latter with a reducing agent to obtain a cis racemic compound of formula I and optionally resolving the latter with a resolution agent to obtain the desired optical form and novel intermediates.

Preparation of 4-phenyl-1,2,3,6-tetrahydropyridines

A compound of the formula ##STR1## wherein R is hydrogen or an ester remainder, X is hydrogen or fluorine and Y combined with the doted lines represents ##STR2## or X is hydrogen and and Y combined with the dotted lines is ##STR3## and R.sub.1 is the remainder of an enol ether or ester.

Intermediates for the preparation of 6.alpha., 9.alpha.-difluoro steroids

A process for the preparation of 6.alpha.,9.alpha.-difluoro steroids of the formula ##STR1## wherein R is hydrogen or an ester remainder.

Preparation of 6.alpha., 9.alpha.-difluoro steroids

Mixtures of compounds of ##STR1## or a mixture of the latter and a compound of the formula ##STR2## which are useful intermediates for the preparation 20-keto-21(S)-hydroxy steroids.

Preparation process for 20-keto 21(S) hydroxy steroids compounds and

An improved process for the preparation of 20-keto-21(S)-hydroxy steroids of the Formula ##STR1## wherein R.sub.1 is alkyl of 1 to 3 carbon atoms, R.sub.2 is alkyl of 1 to 12 carbon atoms, and R.sub.3 is alkyl of 1 to 4 carbon atoms and novel intermediates therefrom.

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Rosny Sous Bois, France

Christian Richard