Pergamon 0031-9422(95) 00452-1 Phytochemistry, Vol. 40, No. 5, pp. 1563 1565, 1995 Copyright © 1995 Elsevier Science Ltd Printed in Great Britain. All rights reserved 0031-9422/95 $9.50 + 0.00 2,7-DIHYDROXY- 3-FORMYL- 1-(3'-METHYL-2'-BUTENYL)CARBAZOLE FROM CLAUSENA LANSIUM VIJAY KUMAR,* KAYALVILY VALLIPURAM,ADELEKE C. ADEBAJO~"and JOHANNES REISCH3~ Department of Chemistry, University of Peradeniya, Peradeniya, Sri Lanka; fDepartment of Pharmacognosy, Obafemi Awolowo University, lle-Ife, Nigeria; :~(deceased) lnstitut fiir Pharmazeutische Chemie, Westf~ilische Wilhelms Univerit~it, 48149 Miinster, Germany (Received in revisedform 22 March 1995) Key Word lndex--Clausena lansium; Rutaceae; root bark; coumarins; carbazole alkaloids; 2,7- dihydroxy-3-formyl-1-(3'-methyl-2'-butenyl)carbazole. Abstract--Clausena lansium root bark contained chalepensin, chalepin, gravelliferone, angustifoline, indizoline and the new carbazole alkaloid, 2,7-dihydroxy-3-formyl-l-(3'-methyl-2'-butenyl)carbazole. INTRODUCTION Clausena lansium is a shrub which has been introduced into Sri Lanka. Its roots and fruits are utilized in Chinese folk medicine [1], while its leaves are used in Sri Lanka as a substitute for curry leaf in cooking. Previous studies on C. lansium include the isolation of carbazole alkaloids from the root [1] and leaf [2], and a secondary amine from the leaf [2]. We now report the presence of four coumarins, chalepensin, chalepin, gravelliferone and an- gustifolin, together with sitosterol and the carbazole al- kaloids, indizoline and the new 2,7-dihydroxy-3-formyl- 1-(Y-methyl-2'-butenyl)carbazole. RESULTS AND DISCUSSION The dichloromethane extract of C. lansium root bark contained the 3-(1', l'-dimethylallyl) coumarins, chalepen- sin (1), chalepin (2), gravelliferone (3) and angustifolin (4), together with sitosterol and two carbazole alkaloids, indizoline and a new carbazole, 2,7-dihydroxy-3-formyl- 1-(3'-methyl-2'-butenyl)carbazole (5). The 13 C NMR data of 1-4 which have not been previously reported are given in Table 1. Carbazole 5 gave a yellow colour with Dragendorff's reagent and its UV spectrum was characteristic of car- bazole alkaloids. The IR spectrum of 5, molecular for- mula C18HtTO3N from HR mass spectrometry, showed a broad band at Vmax 3500-2400cm -1 for chelated OH and NH groups and an intense peak at Vmax 1660--1610 cm- 1 for a carbonyl group. *Author to whom correspondence should be addressed. 1 2 R 3: CH2-CH=CMe 2 4: H 5 4 ~ CHO .o- v, -o. 4 ' ~ 5' 7 6 ~ CHO HO-' ~ '~ ~ "O The 1HNMR spectrum of 5 contained two methyl singlets, a CH2 doublet and a CH triplet characteristic of an isopentenyl substituent on an aromatic ring. A singlet at ~9.80 indicated the presence of an aldehyde group, while molecular formula considerations suggested that two hydroxyl substituents were also present. Four aro- matic proton signals in its 1H NMR spectrum gave addi- tional evidence that 5 was a tetrasubstituted carbazole. 1563