4,24-Dioxa-9,22-diazatetracyclo(19.3.1.1(10,14).0(3,5))hexacosane, maytansine deriv. 78987-28-7 B820915K135 DEMETHYLTREWIASINE B820915K135 Demethyltrewasine Demethyltrewiasine Maytansine, N(2')-deacetyl-N(2')-demethyl-15-methoxy-N(2')-(2-methyl-1-oxopropyl)- Maytansine, N2'-deacetyl-N2'-demethyl-15-methoxy-N2'-(2-methyl-1-oxopropyl)- N'-Demethyltrewiasine NSC348700