1H-Pyrano(3',4':6,7)indolizino(1,2-b)quinoline-11-hexanoic acid, 4-ethyl-3,4,12,14-tetrahydro-4-hydroxy-3,14-dioxo-, methyl ester, (S)- 89808-79-7 Methyl (S)-4-ethyl-3,4,12,14-tetrahydro-4-hydroxy-3,14-dioxo-1H-pyrano(3',4':6,7)indolizino(1,2-b)quinoline-11-hexanoate