Csir

Aeci Limited

Christopher John Parkinson

Neil Stockenstrom Gardiner

Stephanus Francois Marais

Jennifer Ann Chaplin

Dean Brady

Lucia H Steenkamp

Etienne Van Eeden Skein

Robin Kumar Mitra

Shavani Reddy

Madrie Portwig

Deborah Nicole Davidson

Dana Helen Braithwaite

Butana Andrew Mboniswa

Owen Lungile Njamela

Thebeeapelo John Khaile

Melanie Daryl Evans-Dickson

Christa Maria Jungmann

A process of separating a single desired stereoisomer from a racemic mixture of eight stereoisomers of a compound of formula (III), wherein Rrepresents an isopropanol group, an isopropyl group or an isopropylene group, includes the steps of: contacting the racemic mixture in a suitable organic solvent with an esterifying agent and a stereospecific enzyme which stereoselectively esterifies the &#x2014;OH group of the desired stereoisomer, for a time sufficient to convert a desired percentage of the desired stereoisomer to a compound of formula (IV), wherein Ris as defined above and Ris an alkyl or an aryl group, to give a first reaction product including the compound of formula (IV), the organic solvent, the unconverted stereoisomers of the compound of formula (III), excess esterifying agent and by-products of the reaction; and separating the compound of formula (IV) from the first reaction product. The process is of particular application for the production of (&#x2212;)-menthol

Process for preparing (-) menthol and similar compounds

A process for the production of disubstituted propionic acid derivatives which are intermediates in the synthesis of .alpha.-arylpropionic acids such as naproxen, involves the reaction of a naphthalene derivative such as 2-methoxynaphthalene, with an alkylating agent such as an alkyl pyruvate in the presence of a catalyst, and then dehydrating and hydrogenolising, or directly hydrogenolising, or derivatising and then hydrogenolising the product thereof, to produce the desired compound.

Synthesis and resolution of propionic acid derivatives

Growing community of inventors

Modderfontein, South Africa

Christopher John Parkinson