| 摘要 |
<p>It is intended to provide a process for conveniently producing on an industrial scale an optically active α-methylcysteine derivative or its salt in the form of an L- or D-compound, which is useful as an intermediate of a drug, etc., from a less expensive and easily available material. Namely, a process for producing an optically active α-methylcysteine derivative or its salt in the form of an L- or D-compound which comprises D-selectively cyclizing a racemic N-carbamoyl-α-methylcysteine derivative or its salt with the use of hydantoinase to give a D-5-methyl-5-thiomethylhydantoin derivative or its salt and N-carbamoyl-α-methyl-L-cysteine derivative or its salt, and then deblocking and hydrolyzing the amino group and the sulfur atom of each product.</p> |
