(9aS,13aS)-2,8-Dioxo-5,6,9,9a,10,11,12,13-octahydro-2H,8H-pyrano[4',3':3,4]pyrido[2,1-i]indole-4-carboxylic acid methyl ester 在
sodium hydroxide 、 sodium tetrahydroborate 作用下,
生成 (9aS,13aS)-2,8-Dioxo-1,4,5,6,9,9a,10,11,12,13-decahydro-2H,8H-pyrano[4',3':3,4]pyrido[2,1-i]indole-4-carboxylic acid