Three new monomeric carbazole alkaloids, 3-formylcarbazole (1), N-methoxy-3-formyl-carbazole (2), and pyrayaquinone-C (3), and two new binary carbazoles, murrafoline-E (4) and murrafoline-F (5), were isolated from root bark of Murraya euchrestifolia hayata (rutaceae) collected in Taiwan, and their structures were elucidated. © 1988, The Pharmaceutical Society of Japan. All rights reserved.