INTRODUCTIONThe small and simple benzothiazole nucleus is present in compounds involved in research aimed at evaluating new products that possess interesting biological activities like- antitumour1-4, antimicrobial5-7,, antitubercular8, antimalarial9, anticonvulsant10,11, anthelmintic12, analgesic and anti-inflammatory activity.13,14 The benzothiazole ring is present in various marine or terrestrial natural compounds, which have useful biological activities. Heterocycles containing the thiazole moiety are present in many natural products such as bleomycin, epothilone A, lyngbyabellin A & dolastatin 10.15 Benzothiazole is a privileged bicyclic ring system. Due to their important pharmaceutical utilities, the synthesis of these compounds is of considerable interests. Chemistry of benzothiazole nucleusBeing a heterocyclic compound, benzothiazole finds use in research as a starting material for the synthesis of larger, usually bioactive structures. Its aromaticity makes it relatively stable, although as a heterocycle, it has reactive sites, which allow for functionalization. Benzothiazole is a colorless, slightly viscous liquid with a melting point of 2C, and a boiling point of 227-228 C. The density of benzothiazole is home buyers 1.644 gm/ml, and molecular mass is 139.19 gmol-1. Benzothiazole has no household use. It is used in industry and research. Structure of benzothiazole (C7H5NS): 1-thia-3-azaindene MEDICINAL IMPORTANCE of Benzothiazole NUCLEUS A large number of therapeutic agents are synthesized with the help of Benzothiazole nucleus. During recent years there have been some interesting developments in the biological activities of benzothiazole derivatives. These compounds have special significance in the field of medicinal chemistry due to their remarkable pharmacological potentialities. Benzothiazole with analgesic activity: Series of sulphonamide derivatives were prepared by condensation of 2-(4-aminophenyl sulphonamido)-6-substituted benzothiazoles with alkyl isothiocynates by Siddiqui et al (2004).13 The compound (1) with methoxy substitution showed maximum analgesic activity in the series. (1) 6-fluoro-7-substituted-2-(1,3-oxazolo[3,2-b][1,2,4]triazo-3-amino) benzothiazoles and 6-fluoro-7-substituted-2-(1,3-thiazolo[3,2-b] [1,2,4] triazol-3-amino) benzothiazoles were synthesized by Gurupadayya et al (2005).14 The compounds (2a and 2b) exhibited 60% and 71.79% analgesic activity.