title: Letter: Novel maytansinoids. Structural interrelations and requirements for antileukemic activity.
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000302:isolation & purification*; D055598:Chemical Phenomena; D002621:Chemistry; D009025:Morpholines / Q000302:isolation & purification; D013329:Structure-Activity Relationship
chemical_list: D000903:Antibiotics, Antineoplastic; D009025:Morpholines