CARBOXYLIC TERMINAL DETERMINATION IN SIMPLER PEPTIDES BY SELECTIVE REDUCTION OF CARBOXYLIC GROUP BY SODIUM DIHYDRO BIS‐(2‐METHOXYETHOXY) ALUMINATE

The terminal carboxylic group in acylamino acids and peptides is selectively reduced by sodium dihydro bis‐( 2‐methoxyethoxy ) aluminate to alcoholic group. On hydrolysing the reduced acylamino acids or peptides, the original carboxy terminal amino acid is liberated as amino alcohol which can be easily identified. The reaction of reduced N‐acylamino alcohol with carbonyl diimidazole yields an N‐acyl‐2‐oxazolidone derivative from which the N‐acyl group is easily removed producing 2‐oxazolidone. The possibility of selective cleavage of the terminal amino alcohol and its characterisation as 2‐oxazolidone derivative has been investigated.