Constituents of Clausena excavata. Isolation and structural elucidation of seven new carbazole alkaloids and a new coumarin

Abstract

Seven new carbazole alkaloids, named clauszoline-A (1), -B (2), -C (3), -D (4), -E (5), -F (6), and -G (7), and a new coumarin named 5-geranyloxy- 7-hydroxycoumarin (8) were isolated from stem bark of Clausena excavata (Rutaceae) collected in Singapore, and their structures were elucidated by means of spectral methods.