Abstract. Cz0Hz6NzO2, M r = 326.1994, orthorhombic, P2~2~2~, a = 12.710(4), b = 10.115(1), c = 13.035 (4) A, U= 1675.9 (8) A 3, Z = 4, D C = 1.294 g cm -3, 2(Cu Ka) = 1.54178 ,/~, R = 0.045 for all 1532 observed reflections. Aristotelinine, (3S,4aS,5R,-10bR, 11 aR, 13R) -1,2,3,4,4a,5,11,11 a-octahydro-2,2,5-trimethyl-3,5 -ethano -10bH-pyrido[3,2-blcarbazole10b,13-diol, is a unique indole-type alkaloid isolated from the leaves and stems of A ristotelia chilensis. The nature of the ring fusions and the tertiary hydroxyl group in the five-membered ring of the indole moiety are interesting features of this alkaloid.