(4S)-4-ethyl-4-hydroxy-11-(4-hydroxybutan-2-yl)-1H-pyrano[3',4':6,7]indolizino[1,2-b]quinoline-3,14(4H,12H)-dione

butyl 3-methyl-4-phenylsulfanylpent-2-enoate

n-butoxytri(sec-butyl)silane

tri(butan-2-yl)silane

butyl 2-methylbenzoate