The functionalization of organic molecules with the Schiff bases having benzothiazole moiety has grown rapidly due to its multiple therapeutic and pharmacological properties. They have driven enormous studies on their stereochemistry, bioactivity and synthetic attempts. The benzothiazole moiety is infinitesimal but broadly used for industrial purposes and also exhibits a broad range of biological activities. Study carried out on Schiff bases having benzothiazole had well-known promising activities like antimicrobial, antimalarial, antifungal, antitubercular, antiviral, antitumor, analgesic, anti-inflammatory and many more. This review brings forward a systematic and comprehensive survey of the reactivity and biological properties associated with the Schiff bases-benzothiazole derivatives and their analogs.

A series of 6-chloro-N-(substituted benzylidene)benzothiazol-2-amine (3 a-e) have been synthesized under microwave irradiation and conventional heating for comparison. 2-Amino-6-chlorobenzothiazol (2) was condensed with substituted aromatic aldehyde in ethanol/DMF in the presence of glacial acetic acid as a catalyst under conventional heating and microwave irradiation to yield the Schiff base respectively (3 a-e). 2-Amino-6-chlorobenzothiazole (2) was synthesized by the reaction of p-chloroaniline (1) and KSCN in glacial acetic acid in presence of Br2 as a catalyst. Further, these Schiff bases were purified by column chromatography over silica gel using hexane: ethyl acetate (7:3) as an eluent. The structures of synthesized compounds were confirmed by IR, 1 H NMR, 13 C NMR, and Mass Spectral data.Microwave irradiation of organic reactions has gained popularity as it accelerates the reaction towards a variety of synthetic transformations, solvent-free procedures, decreased in reaction time, higher yields and easier work up as compared to conventional methods. Chemical transformations that took hours or even days to complete can now be accomplished in minutes. 1 Also the use of microwave for the synthesis of organic compounds has proved to be efficient, safe and environmentally benign techniques with shorter reaction time. 2 Benzothiazoles are bicyclic ring system, consist of a 5-membered 1,3-thiazole ring fused with a benzene ring. Benzothiazole derivatives have been studied and found to have various chemical reactivity and pharmacological activities such as antibacterial, 3 antimicrobial, 4 antidiabetic, 5 antitumor, 6 anti-inflammatory, 7 anthelmintic 8 activities and many more. The presence of hydrophobic moieties in benzothiazole derivative shows cytotoxic activity against cell lines. The -NH2, -OH, -Cl group containing benzothiazole shows better anticancer activity. 9 Azomethine groups (-C=N-) typically known as Schiff bases have been synthesized by the condensation