Enantioselective synthesis of both enantiomers of 2-amino-2-(2-furyl)ethan-1-ol as a flexible building block for the preparation of serine and azasugars

A short synthesis of d-[1-(14) C]-serine of high enantiomeric purity

Herein, we report a short, three-step synthesis of d-[1-(14) C]-serine (4) in high enantiomeric purity. Starting from [(14) C]-KCN and 2-(benzyloxy)acetaldehyde, Strecker reaction using (R)-1-phenylethylamine as the chiral auxiliary gave two diastereomeric aminonitriles 1 and 2 in the ratio of 4:3, which were conveniently separated and purified chromatographically. Following hydrolysis and subsequent hydrogenolysis, the purified major diastereomer 1, was smoothly converted to d-[1-(14) C]-serine (4) in an enantiomeric excess of >99%, thus circumventing time intensive chiral HPLC enantiomeric resolution.