In connection with a program in our laboratory directed toward the total synthesis of pyrrolophenanthridinium alkaloids for antitumor screening, 2 we required a short and general approach to the Narcissus tortuosus constituent tortuosine, 1, 3 its structural relative criasbetaine, 2, 4 from Crinum asiaticum, and ungeremine, 3. 5 Structure-activity relationship (SAR) data for antitumor efficacy within the small class of known Amaryllidaceae ...