A series of novel 2-(5-substituted-[1, 3, 4] oxadiazol-2-yl)-benzoxazoles (7a–h) were synthesized in good yields in two different directions by involving benzoxazole-2-carboxylic acid (1) as raw material and benzoxazole-2-carbonyl chloride (2), benzoxazole-2-carboxylic acid methyl ester (3), benzoxazole-2-carboxylic acid hydrazide (4), benzoxazole-2- carboxylic acid N′-acetyl hydrazide (5a–d) and benzoxazole-2-carboxylic acid- ...