Several sulphur & nitrogen containing heterocyclic compounds have been studied because of their interesting biological properties such as Anti-bacterial, Anti-fungal, Anti-hypertensive, Anti-HIV, Anti-inflammatory, Anti-microbial, Anti-rheumatic, Aldose reductase inhibitor, ATP-sensitive potassium channel opener. 1,4-Benzothiazine forms an important class of heterocyclic system. Several studies are available for 1, 4-Benzothiazine formation and their application in drugs. 1, 4-benzothiazine and thiazoles constitute an important class of sulfur and nitrogen heterocytes. The utility of thiazole as medicaments is finally established. Recently that attention is being directed towards the synthesis of 1,4-benzothiazine, as they are structurally analogues to phenothiazine nucleus. Luciferin and rifamycin are 1,4-benzothiazine derivatives and are obtained by biosynthesis and found to posses immense pharmacological activities and also have application is dyestuff, photographic developer, UV light absorber and antioxidants.