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TAXOL

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6. Conclusion
Taxol has proved itself in clinical trials and regular treatments to be a very powerful anticancer drug proving to be a life saver for thousands of patients with leukaemia, solid tumours in the breast, ovary, brain, or lung3.   However, supplies have been restricted due to environmental concerns leading to taxol being too expensive for treatment of non private patients.  This huge gap in the supply and demand has lead to many patients being denied treatment that may have cured them.  Hence much effort has been directed into the artificial synthesis of taxol and its analogues.  To date (23/02/98) three complete syntheses of taxol have been disclosed11,12,13,15,16,17 with several other groups close to completing their work. A semi-synthesis from 10-deacetylbaccatin III, a precursor of taxol lacking the C-13 side chain. and the C10 acetoxy group , that can be isolated from the twigs and needles of the European Yew tree (Taxus baccata) has also been developed.

Taxol stood for more than two decades as a challenge to synthetic chemists, pointing out the weakness of the science of organic synthesis to construct highly oxygenated and congested polycyclic frameworks10.  With the syntheses proposed by the Nicolaou11, Holton15 and Danishefsky17 groups a major barrier has been overcome and new avenues opened.  Current research groups are using the methods developed by the above groups in order to synthesise a range of taxol analogues.  The syntheses devised are, however, very complicated and involved and hence the problem still remains of how to convert the small scale syntheses that can be conducted in the laboratory into a feasible method for  large scale industrial production.  Until a simpler synthesis is devised the only large scale source of taxol will be from harvesting natural supplies and then semi-synthesis.   This means that for the foreseeable future the cost of taxol is going to remain too high for wide scale treatment of patients resulting in the death of people this drug could have conceivably helped.