Preparation of optically active amino acid derivatives of some methylated 5-amino-azaheterocycles

The present paper describes the reduction of 1-methyl-5-nitro-benzimidazole s (1A, 2A) and 1,3-dimethyl-2H-5-nitro-benzimidazol-2-one (3) to 5-aminoben zimidazoles (4A, 5A) and 1,3-dimethyl-2H-5-amino-benzimidazol-2-one (6) res pectively with hydrazine hydrate in absolute ethanol in the presence of gra phite. Compounds 5A and 6 were converted to 2-ethyl-5-(phthaloyl-L-phenylal anyl)amino-1-methylbenzimidazole (7) and 1,3-dimethyl-5-(phthaloyl-L-phenyl alanyl)aminobenzimidazol-2-one (8). Characterization of the synthesized com pounds was done with the help of mass spectrometry and H-1 NMR spectroscopi c studies. Optical activity of the amino acid derivatives 7 and 8 was also recorded.