ANTIMITOTIC AND CYTOTOXIC COMPOUNDS FROM TROPICAL PLANTS

Abstract

Starting from the discoveries of navelbine and taxotere, two potent analogs of natural antitumour compounds, the search of new antitumour drugs has continued at Gif-sur-Yvette, by associating classical cytotoxicity assays with other mechanism involved in the cell replication pathway. The tubulin-microtubules system, an easy and efficient method, is one of the targets used in finding new antimitotic drugs. Through various research programmes in tropical countries and in the framework of the long-term cooperation between the University of Malaya and CNRS, a number of molecules have been shown to possess activity on tubulin. Among them, rhazinilam, isolated from a Malaysian Kopsia, K. singapurensis Ridley, Apocynaceae. It has specific activity on microtubules. Studies of structure-activity relationships guided by the tubulin-test have led to a better knowledge of the properties of rhazinlam and to the design of analogs. Cytotoxic prenylxanthones have also been isolated from Vietnaamese Garcinia, G. nigrolineata (Clausiaceae). Nigrolineatin and its analogues possess anti-oncogene activity on FPTase. Other xanthone derivatives like xanthochymol were isolated from a Malaysian Garcinia, G. pyrifera and were found to possess activity on tubulin. Structure-activity relationships studies on these series have been done.


Key Words: Antimitotic properties, Tubulin, Kopsia singapurensis, rhazinilam, Garcinia species, xanthones


Nig. J. Nat Prod. And Med. Vol.3 1999: 9-14