4-hydroxy-3-(3-methylbutanoyl)-2-methylmercapto quinoline

4-chloro-3-(3-methylbutanoyl)-2-methylmercaptoquinoline

4-chloro-3-(3-methyl-2-butenoyl)-2-methylmercapto quinoline

2-isopropyl-4-methylmercapto-3(2H)-oxofuro(3,2-e)quinoline

ethyl 3-keto-5-methyl-2-[phenylamino(methylmercapto)methenyl]hexanoate