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South African Journal of Botany 2003, 69(4): 593–594 Copyright © NISC Pty Ltd Printed in South Africa — All rights reserved SOUTH AFRICAN JOURNAL OF BOTANY EISSN 1727–9321

Short Communication

Alkaloids from Cyrtanthus falcatus

EE Elgorashi and J van Staden*

Research Centre for Plant Growth and Development, School of Botany and Zoology, University of Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa * Corresponding author, e-mail: [email protected]

Received 9 June 2003, accepted in revised form 7 July 2003

The alkaloids papyramine, epipapyramine, maritidine, The structures of these alkaloids were determined by O-methylmaritidine and tazettine were isolated from the spectroscopic methods. methanolic extracts of the bulbs of Cyrtanthus falcatus.

Cyrtanthus falcatus R.A. Dyer (Amaryllidaceae) is one of Fractions B and C were combined (9g) and subjected to about 40 Cyrtanthus species found in southern Africa. It is column chromatography (35cm x 4cm) using silica gel 60 found mainly in the Natal midlands, always below 1 800m (200g) and dichloromethane mixed gradually with 2%, 5%, (Reid and Dyer 1984, Hilliard 1990). Cyrtanthus falcatus is 10%, 20%, 40% and 50% methanol as eluent. Different frac- characterised by a globose bulb of about 50–100mm in tions (50ml) were examined by silica gel thin layer chro- diameter. The bulb has a long neck usually covered in old matography and sprayed with Dragendorff’s reagent. leaf bases. The leaves, which are up to 50mm broad are Fractions of similar content were combined. Fractions present at flowering. Flowers are pendulous with a tubular (48–56) were further separated on preparative thin layer green to yellow-orange perianth. chromatography using dichloromethane : methanol : acetic Little is known about the chemistry and usage of C. falca- acid (44:4:0.5) to give 175mg of papyramine and epipapyra- tus apart from the detection of the alkaloid galanthamine mine (mixture of two epimers 1, 2) and O-methylmaritidine 3 using a radioimmunoassay (Tanahashi et al. 1990). Related (35mg). Fractions (80–82) and (93–113) yielded maritidine 4 Cyrtanthus species, however, are used in Zulu traditional (23mg) and tazettine 5 (59mg) respectively (Figure 1). medicine for the treatment of scrofula, chronic coughs, Structures of the isolated alkaloids were determined by headache, cystitis, leprosy, roundworm and tapeworm. They spectroscopic and physical methods. NMR spectra were are also used during pregnancy to ensure easy labour. recorded with a Varian 500 instrument with tetramethylsilane Spiritually, they are used as love charm emetics and protec- as internal standard. EIMS were obtained using an agilent tive sprinkling charms against storm and evil (Watt and 6890 GC with a 5973N mass selective-MS system. The Breyer-Brandwijk 1962, Hutchings et al. 1996). structures were further confirmed by comparison with those The family Amaryllidaceae contains a group of isoquino- reported in the literature. line alkaloids, Amaryllidaceae alkaloids, which are found The methanolic extracts of the bulb of Cyrtanthus falcatus exclusively in its member species. The aim of this study was yielded the alkaloids payramine and epipyramine, mixture of the isolation and structural elucidation of the alkaloid con- two epimers 1, 2 (Bastida et al. 1990, Suau et al. 1990), stituents of C. falcatus as part of our continuous investiga- maritidine 4 (Ghosal et al. 1985), O-methylmaritidine 3 tion of the Amaryllidaceae alkaloids. (Suau et al. 1990) and tazettine 5 (Codina et al. 1990). Plants of Cyrtanthus falcatus were obtained from Green The occurrence of the alkaloids papyramine and epipa- Goblin Nursery, Durban. The identity of the plant was con- pyramine as a mixture of two epimers has been reported for firmed by Prof. TJ Edwards, curator, Herbarium, University Narcissus panizzianus and N. papyraceus (Bastida et al. of Natal Pietermaritzburg. A voucher specimen (Elgorashi 6 1990, Suau et al. 1990). Similar results of inseparable mix- NU) was deposited in this herbarium. tures of two epimers have been reported for C-6 hydroxy- Dried and powdered bulbs (390g) were macerated in crinane alkaloids such as hydroxycrinamine (Viladomat et al. methanol (1.25l x 3) for 72h. The crude extract was dis- 1996) and hydroxybuphanisine (Abu-Donia et al. 2002). solved in 4% acetic acid (200ml) and then extracted with The alkaloid tazettine has been detected in a number of diethyl ether (200ml x 3) to give fraction A. The solution was South African Amaryllidaceae. These are Crinum moorei, then basified using ammonia solution to pH 9 and extracted Haemanthus albiflos, Nerine crispa, N. masonorum and N. with diethyl ether (200ml x 3) and ethyl acetate (200ml x 3) sarniensis (Viladomat et al. 1996). Investigation has to give fractions B and C respectively. revealed that tazettine is an artifact of the isolation proce- 594 Elgorashi and Van Staden

OMe olar non-tumoral fibroblasts (Weniger et al. 1995). It has also shown a slight transient fall in blood pressure at 8.71mg kg–1 in dogs but showed a lack of an analgesic effect when administered subcutaneously in mice at a concentration of MeO 100mg kg–1 (Wildman 1960). Papyramine, on the other hand, was active against human lymphoid neoplasm and murine alveolar non-tumoral fibroblasts (Weniger et al. 1995). The five alkaloids have been detected in a number of N Amaryllidaceae plants (Ghosal et al. 1985, Bastida et al. MeO 1990, Codina et al. 1990, Suau et al. 1990). These alkaloids R2 are known to occur exclusively in members of the family R1 Amaryllidacae. Their presence in Cyrtanthus falcatus is in 1 R1=H, R2=OH line with these findings. 2 R1=OH, R2=H Acknowledgements — The authors thank the University of Natal Research Fund and the National Research Foundation, Pretoria, for financial support. R References

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