6-O-[3-(3-quinoyl)-2propen-1-yl]-9-keto-2',4''-benozoate-11,12-cyclic carbamate erythromycin A Suppliers, 6-O-[3-(3-quinoyl)-2propen-1-yl]-9-keto-2',4''-benozoate-11,12-cyclic carbamate erythromycin A Manufacturers.