Cholinesterase inhibiting, antileishmanial and antiplasmodial steroidal alkaloids from Sarcococca hookeriana of Nepalese origin

The plants of genus Sarcococca (Family Buxaceae) have an extensive use in folk medicine around South Asia including China and Japan. The popular use of these plants includes the treatment of pain, rheumatism, malaria, skin diseases, gonorrhoea etc. This genus is an important producer of 5α-pregnane type steroidal alkaloids, and most of them have been reported to exhibit anticholinesterase, antibacterial, antitumour, antileishmanial, antiplasmodial and antiulcer activities [1–4]. During our phytochemical investigation on S. hookeriana of Nepalese origin, we have isolated 11 new and 8 known steroidal alkaloids. Some of these compounds were subjected to different chemical reactions, by which 10 new derivatives were obtained [5]. We have also performed microbial transformation of compound dictyophlebine by a fungus Rhizopus stolonifer that resulted one new and two known metabolites [6]. The structure elucidation of these compounds was carried out by modern spectroscopic techniques. All these compounds were subjected to acetyl- and butyrylcholinesterase inhibition assays and were shown moderate to potent activities [1,2,4–6]. Similarly, most of these compounds were screened for antileishmanial and antiplasmodial properties and found to possess moderate to potent activities [3,4].

Acknowledgements: We wish to acknowledge Alexander von Humboldt Foundation, Germany for providing post doctoral fellowships to K. P. Devkota at Bielefeld University.

References:

1. Choudhary, M. I. et al. (2004) Helv. Chim. Acta 87:1099–1108.

2. Choudhary, M. I. et al. (2005) Steroids 7:295–303.

3. Devkota, K. P. et al. (2007) Nat. Prod. Res. 21:292–297.

4. Devkota, K. P. et al. (2007) Chem. Pharm. Bull. 55:1397–1401.

5. Devkota, K. P. et al. (2007) Z. Naturforsch. 62b:1324–1328.

6. Devkota, K. P. et al. (2007) Chem. Pharm. Bull. 55:682–684.