Butanedioic acid, (4S)-4,11-diethyl-3,4,12,14-tetrahydro-4-hydroxy-3,14-dioxo-1H- pyrano[3',4':6,7]indolizino[1,2-b]quinolin-9-yl (2R)-3,4-dihydro-2,5,7,8-tetramethyl-2- [(4R,8R)-4,8,12-trimethyltridecyl]-2H-1-benzopyran-6-yl ester