摘要 |
<p>The title compounds are obtained by racemic resolution of D, L-homoalanin-4-yl-(methyl)phosphinic acid by precipitating out one of the diastereomeric salts with chiral bases such as quinine or cinchonine. The yield of desired enantiomers can be increased by transformed racemic resolution, the diastereomeric salt being precipitated when the undesired enantiomer is racemised in the presence of (hetero)aromatic aldehydes. The racemisation method is also suitable for optically active amino acids having other structures.</p> |