(S)-Hexahydropyrrolo(1,2-a)pyrazine-1,4-dione-4-17O 97011-16-0 Cyclo(pro-O-gly) Cyclo(pro-gly) Cyclo(prolylglycyl) Pyrrolo(1,2-a)pyrazine-1,4-dione-4-170, hexahydro-, (S)- Pyrrolo(1,2-a)pyrazine-1,4-dione-4-17O, hexahydro-, (S)-