| 摘要 |
The preparation of (S)-cyanohydrins by reaction of the corresponding oxo compounds with hydrocyanic acid can be achieved enzymatically with the aid of oxynitrilase (4.1.2.11) from Sorghum bicolor. This is preferably carried out in aqueous medium at pH values below 6.0, in particular below 4.5, in order to suppress competing chemical reactions and racemisations. The reaction temperatures are, in particular, between -5 DEG C and +50 DEG C. Of particular interest is the reaction of aromatic aldehydes, specifically benzaldehyde and its derivatives, and the generation of aldononitriles by reaction of aldoses, especially of sugars with 3 to 9 carbon atoms, with hydrocyanic acid. |
