7-METHOXY-4-METHYL-6,8-DIOXO-3,4,6,8,12,12A-HEXAHYDRO-2H-(1,3)OXAZINO(3,2-D)PYRIDO(1,2-A)PYRAZINE-9-CARBOXYLIC ACID, (4R,12AS)-
7-methoxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2h-(1,3)oxazino(3,2-d)pyrido(1,2-a)pyrazine-9-carboxylic acid, (4r,12as)-