Progress in the Synthesis of 2-Aminobenzothiazoles

2-Aminobenzothiazoles are an important class of N-heterocyclic compounds which have been widely available in numerous bioactive compounds such as pharmaceuticals and agrochemicals. Due to the versatile biological activities, great attention has been paid to their synthesis. Therefore, multitudinous synthetic approaches have been developed for accessing these compounds, including the intramolecular cyclization of arylthioureas via C-H functionalization/C-S bond formation, the intramolecular cyclization of 2-haloarylthioureas via dehydrogenative C-S bond formation, and the intermolecular C-N cross-coupling of benzothiazole with amines, 2-chlorobenzothiazole with amines, 2-aminobenzothiazole with aryl halides, etc. In this paper, the syntheses of N-substituted 2-aminobenzothiazoles are systematically reviewed, and their synthetic methods are also classified and summarized based on the varieties of the utilized substrates. Finally, the future perspective of these compounds is described.