Novel alkaloids, lythranine (III), lythranidine (VI), and lythramine (VII), were isolated from Lythrum anceps Makino. Lythranine, C28H37O5N5 was hydrolyzed with weak alkali to give lythranidine, C26H3504N. Lythranine on reaction with formalin gave lythramine, C29H3705N. Functional groups were investigated on these alkaloids and all of the O- and N-functions were clarified. © 1970, The Pharmaceutical Society of Japan. All rights reserved.