PREPARATION OF (S)-2-SUBSTITUTED SUCCINATES BY STEREOSPECIFIC REDUCTIONS OF FUMARATE AND DERIVATIVES WITH RESTING CELLS OF CLOSTRIDIUM-FORMICOACETICUM

Fumarate derivatives have been reduced to (S)-2-methylsuccinate 2a, (S)-2-ethylsuccinate 3a and (S)-2-chlorosuccinate 4a in up to 1 M concentrations with Clostridium formicoaceticum. Formate was the electron donor and viologens or anthraquinone-2,6-disulphonate acted as artificial electron mediators. Reductions with freeze-dried cells in (H2O)-H-2-buffers led to the (2R,3S)-[2,3-H-2]-dideuterated succinate derivatives. The productivity numbers(1) ranged from 450 to 5000 and the enantiomeric excess of all (S)-2-substituted succinates was greater than or equal to 99%.