ABSTRACT A study of reaction of methyl substituted phenols with a,13 unsaturated acids in presence of polyphosphoric acid afforded a mixture of corresponding xanthone and fluorenone derivatives which constitute an important class of naturally occurring as well as synthetic compounds. Subjecting the crude reaction mixture to careful chromatography resulted in the separation of the two compounds. t,t,i 2 aft. ORIGINAL RESEARCH ARTICLES A VERSATILE ROUTE FOR SYNTHESIS OF XANTHONES AND FLUORENONE DERIVATIVES Cherian E. and Patani A.* (Received 20 January 2009) (Accepted 11 February 2009) Keywords: Xanthone, Fluorenone, Methyl substituted phenols,a,3 - unsaturated acids. INTRODUCTION Xanthones Xanthones which is dibenzo-y-pyrone form an important class of organic compounds which are either naturally occurring or are synthesised. The parent compound does not, so far as is known, occur in nature, but a number of its oxygenated derivatives have been isolated from a variety of natural sources. The flavonoids' and the chromones2 derivatives of xanthones are reported as having varying pharmacological activity such as antibacterial3, analgesic and antipyretic'', antitubercular5' 6• 7, antispasmodic8, anthelmintic9 and antiphlogistic10. Mauss and Wichlinghausen" prepared many such derivatives and found them to possess anthelmintic activity. Few naturally occurring xanthones that have been isolated and characterized occur in the plants as their glycosides 12,13,14 *For correspondence Dr. Patani Scientific and Industrial Research (PSIR) Inga Complex Mahakali caves road Andheri- East, Mumbai- 400093. E-mail: psir79@gmail.com Xanthones in general, occur in various parts of flowering plants belonging to the families Gentianaceae, Guttiferae and Anacardiaceae. Xanthones also occur as metabolic products of members of the lower fungi. A few of the naturally occuring xanthones are listed here: Decussatin, Euxanthone, Euxanthic acid, Corymbiferin, Gentisin, lsogentisin, Griseoxanthone C, Jacareubin, Mangiferin, Lichexanthone, Mangostin, Pinselin and Pinselic acid, Ravenelin, Sterigmatocystin, Swerchirin, Swertianoi and Swertinin. Numerous reports have appeared in literature concerning the efficiency of xanthone and of synthetically produced xanthone derivatives, as commercial pesticides and wood preservatives. Some synthetic xanthones, (carrying basic constituents) are reported to be tuberculostatic and some to be active in schistosomiasis13 . Various synthetic routes which have been adopted for preparing this important class of compounds with versatile applications, also include condensation of 6-hydroxy-2,3-dimethoxy benzoic acid with phioroglucinol followed by methylation to give 0-methyl decussatin, condensation of eve rninic 12 INDIAN DRUGS 46(8) AUGUST 2009 / 610