(2E)-3-De(2-(acetylmethylamino)-1-oxopropoxy)-2,3-didehydro-22-demethylmaytansine 22-Demethylmaysine 52978-29-7 Maysine, 22-demethyl- Maytansine, 3-de(2-(acetylmethylamino)-1-oxopropoxy)-2,3-didehydro-22-demethyl-, (2E)- NSC 219973 Normaysine