(S)-7-(Acetylamino)-5,6,7,9-tetrahydro-1,3-dimethoxy-10-(methylthio)-9-oxobenzo(a)heptalen-2-yl chloroacetate 148731-67-3 2-Catc 2-Chloroacetyl-2-demethylthiocolchicine Acetic acid, chloro-, 7-(acetylamino)-5,6,7,9-tetrahydro-1,3-dimethoxy-10-(methylthio)-9-oxobenzo(a)heptalen-2-yl ester, (S)-