(2R)-2-(3-(3,5-bis(methoxycarbonyl)-2,6-dimethyl-4-(2-nitrophenyl)- pyridine-1(4H)-3-oxoacetyl)amino)-4-(methylthio)butanoic Acid
(2r)-2-(3-(3,5-bis(methoxycarbonyl)-2,6-dimethyl-4-(2-nitrophenyl)- pyridine-1(4h)-3-oxoacetyl)amino)-4-(methylthio)butanoic acid