| 摘要 |
<p>A process for preparing optically active N-substituted azetidine-2-carboxylic acids of the general formula (2) efficiently, simply, easily and industrially advantageously by subjecting an optically active 4-(substituted amino)-2= halogenobutyric acid of the general formula (1) to cyclization in the presence of a base; and novel compounds of the general formula (3) wherein R is a substituted oxycarbonyl type protective group or a substituted sulfonyl type protective group; X is halogeno; and * represents an asymmetric carbon atom.</p> |
