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Alkaloids from an Australian accession of Zanthoxylum nitidum (Rutaceae)
BiochemicalSystematicsand Ecology, Vol. 24, No. 1, pp. 87-W 1996 Copyright0 1996 ElsevierScience Ltd Printedin Great Britain.All rights reserved 0305-1976/96 $15.00+0.00 0305-1978(85)00098-8
Alkaloids from an Australian Accession nitidum (Rutaceae)
of Zanthoxylum
KONG DEYUN, ALEXANDER 1.GRAY, TOM G. HARTLEY” and PETER G. WATERMAN t Phytochemistry
Research Laboratories, Department of Pharmaceutical ‘Australian
Science, University of Strathclyde, Glasgow Gl lXW, U.K.; National Herbarium, GPO Box 1600, Canberra 2601, Australia
Key Word Index-Zanthoxy/um nitidum; Rutaceae; Australia; lignans; triterpenes; benzophenanthridine alkaloids; comparison with collections from other areas.
Subject and Source Zanthoxylum nifidum (Roxb.) DC (Rutaceae) is a morphologically variable species, found as a liane in rain-forest and as a shrub in dryer habitats. It is widely distributed from India and China to northern Queensland, Australia (Hartley, 1966). The material used in this study was collected in northern Queensland and a voucher, Hartley 15146, is deposited at the Australian National Herbarium, Canberra.
Previous Studies Several studies (Mester, 1983; Hisashi et a/., 1984; Zhu et al., 1986; Chen et al., 1989; Fang et a/., 1993). all carried out on material collected in India and China, have shown the presence of a wide range of alkaloids (notably benzophenanthridines) and lignans that are typical of the.Rutaceae.
Present Study Column chromatography and then preparative TLC of petrol, EtOAc and MeOH extracts yielded 12 compounds. Column chromatography of the petrol extract over silica gel eluting with petrol-EtOAc mixtures of increasing polarity gave, in order of elution, p-amyrin, dihydrochelerythrine, (-)-asirinin, (-)-sesamin. Identical treatment of the EtOAc extract gave norchelerythrine, decarine, arnottianamide, 6-methoxy-5,6dihydrofagaridine, liriodenine and decarine acetate, The MeOH extract yielded hesperidin and nitidine. All compounds except 6-methoxy-5,6-dihydrofagiridine were characterized by direct comparison with authentic samples. 6-Methoxy-5,6_dihydrofagaridine, has previously been recorded in Chinese material of Z. nitidum (Chen eta/., 1989) and spectral data were not readily available. Important factors in establishing the structure were the typical UV and ‘H NMR spectra of a 2,3,7,8_tetraoxygenated 5,6-dihydrobenzophenanthridine (Ng eta/., 1984), the presence of an oxymethine (H-6) proton (6 6.61) and a shielded methoxyl resonance (6 3.05) which necessitated placement at C-6 and an nOe enhancement of H-9 by 17% on irradiation of a second methoxyl (6 3.73). which must, therefore, be placed at C-8. These data distinguish from the known isomeric alkaloid 6-hydroxy-5,6_dihydrochelerythrine reported from another rutaceous plant, Toddalia asiatica (Sharma ef al., 1982).
Chemotaxonomic Significance All of the compounds isolated are either already reported from Indian or Chinese material of Z. nitidum or are expectable in that they occur commonly in other species of the genus. These results indicate that Z. nitidum, despite considerable morphological variability that is probably ecologically related, is chemically uniform across its extensive natural range. Acknowledgements-Financial
tAuthor to whom correspondence
support of the Henry Lester Trust (to K.D).
should be addressed.
(Received 11 July 1995; accepted 13 September 1995)
a7
88
K. DEYUN ETAL.
References Chen., Y., Yang, L., Xu, B. and Huang, Z. (1989) HuaxueXuebao 45, 1048 (through CA (1990) 112, 1 75, 616); Hartley, T. G. (1966) J. AmoldArbor. 47, 171 ; Fang, S-D., Wang, L-K. and Hecht, S. M. (1993) J. Org. Chem. 58, 5025; Hisashi, I., Tsutomu, I., Misako, A., Toshiaki, T., Masanao, T., M u n e k a z u , I., Chen, I-S. and Lu, S-T. (1984) Yakugaku Zasshi 104, 1030; i e s t e r , I. (1983) In Chemistry and Chemical Taxonomy of the Rutales (Waterman, P. G. and Grundon, M. F., eds) p. 31, Academic Press, London; Ng, K-M., Gray, A. I, and Waterman, P. G. (1984) Phytochemistry 26, 3251; Sharma, P. N., Shoed, A., Kapil, R. S. and Popli, S. P. (1982) Phytochemistry 21,252; Zhu, W., Tu, Z-B. and Ding, M-L. (1986) J. WuhanBot. Res. 4, 253,
Alkaloids from an Australian Accession nitidum (Rutaceae)
of Zanthoxylum
KONG DEYUN, ALEXANDER 1.GRAY, TOM G. HARTLEY” and PETER G. WATERMAN t Phytochemistry
Research Laboratories, Department of Pharmaceutical ‘Australian
Science, University of Strathclyde, Glasgow Gl lXW, U.K.; National Herbarium, GPO Box 1600, Canberra 2601, Australia
Key Word Index-Zanthoxy/um nitidum; Rutaceae; Australia; lignans; triterpenes; benzophenanthridine alkaloids; comparison with collections from other areas.
Subject and Source Zanthoxylum nifidum (Roxb.) DC (Rutaceae) is a morphologically variable species, found as a liane in rain-forest and as a shrub in dryer habitats. It is widely distributed from India and China to northern Queensland, Australia (Hartley, 1966). The material used in this study was collected in northern Queensland and a voucher, Hartley 15146, is deposited at the Australian National Herbarium, Canberra.
Previous Studies Several studies (Mester, 1983; Hisashi et a/., 1984; Zhu et al., 1986; Chen et al., 1989; Fang et a/., 1993). all carried out on material collected in India and China, have shown the presence of a wide range of alkaloids (notably benzophenanthridines) and lignans that are typical of the.Rutaceae.
Present Study Column chromatography and then preparative TLC of petrol, EtOAc and MeOH extracts yielded 12 compounds. Column chromatography of the petrol extract over silica gel eluting with petrol-EtOAc mixtures of increasing polarity gave, in order of elution, p-amyrin, dihydrochelerythrine, (-)-asirinin, (-)-sesamin. Identical treatment of the EtOAc extract gave norchelerythrine, decarine, arnottianamide, 6-methoxy-5,6dihydrofagaridine, liriodenine and decarine acetate, The MeOH extract yielded hesperidin and nitidine. All compounds except 6-methoxy-5,6-dihydrofagiridine were characterized by direct comparison with authentic samples. 6-Methoxy-5,6_dihydrofagaridine, has previously been recorded in Chinese material of Z. nitidum (Chen eta/., 1989) and spectral data were not readily available. Important factors in establishing the structure were the typical UV and ‘H NMR spectra of a 2,3,7,8_tetraoxygenated 5,6-dihydrobenzophenanthridine (Ng eta/., 1984), the presence of an oxymethine (H-6) proton (6 6.61) and a shielded methoxyl resonance (6 3.05) which necessitated placement at C-6 and an nOe enhancement of H-9 by 17% on irradiation of a second methoxyl (6 3.73). which must, therefore, be placed at C-8. These data distinguish from the known isomeric alkaloid 6-hydroxy-5,6_dihydrochelerythrine reported from another rutaceous plant, Toddalia asiatica (Sharma ef al., 1982).
Chemotaxonomic Significance All of the compounds isolated are either already reported from Indian or Chinese material of Z. nitidum or are expectable in that they occur commonly in other species of the genus. These results indicate that Z. nitidum, despite considerable morphological variability that is probably ecologically related, is chemically uniform across its extensive natural range. Acknowledgements-Financial
tAuthor to whom correspondence
support of the Henry Lester Trust (to K.D).
should be addressed.
(Received 11 July 1995; accepted 13 September 1995)
a7
88
K. DEYUN ETAL.
References Chen., Y., Yang, L., Xu, B. and Huang, Z. (1989) HuaxueXuebao 45, 1048 (through CA (1990) 112, 1 75, 616); Hartley, T. G. (1966) J. AmoldArbor. 47, 171 ; Fang, S-D., Wang, L-K. and Hecht, S. M. (1993) J. Org. Chem. 58, 5025; Hisashi, I., Tsutomu, I., Misako, A., Toshiaki, T., Masanao, T., M u n e k a z u , I., Chen, I-S. and Lu, S-T. (1984) Yakugaku Zasshi 104, 1030; i e s t e r , I. (1983) In Chemistry and Chemical Taxonomy of the Rutales (Waterman, P. G. and Grundon, M. F., eds) p. 31, Academic Press, London; Ng, K-M., Gray, A. I, and Waterman, P. G. (1984) Phytochemistry 26, 3251; Sharma, P. N., Shoed, A., Kapil, R. S. and Popli, S. P. (1982) Phytochemistry 21,252; Zhu, W., Tu, Z-B. and Ding, M-L. (1986) J. WuhanBot. Res. 4, 253,