51568-68-4 7-Ethyl-8-bromo-10-(1'-D-ribityl)isoalloxazine 8-Bromo-7,8-didemethyl-7-ethylriboflavin 8-Bromo-7-ethylriboflavin Riboflavin, 8-bromo-7,8-didemethyl-7-ethyl-