Highly lipophilic benzoxazoles with potential antibacterial activity.

A series of lipophilic 2-substituted 5,7-di-tert-butylbenzoxazoles was prepared in average yields by the reaction of 3,5-di-tert-butyl-1,2-benzoquinone with amino acids and dipeptides bearing N-terminal glycine. Dipeptides having other N-terminal amino acids undergo oxidative deamination. 5,7-Di-tert-butylbenzoxazoles have shown activity against Mycobacterium tuberculosis and some nontuberculous strains where isoniazid has been inactive. Antifungal activity was mediocre.