Synthesis of 6-Hydroxybenzothiazole-2-carboxylic Acid

Abstract

The synthesis of 6-hydroxybenzothiazole-2-carboxylic acid (1) is presented. The benzothiazole ring was obtained by ring contraction of a remarkably stable 2-alkoxy-7-hydroxy-2H-benzo[1,4]thiazine intermediate that could be isolated. 6-Hydroxybenzothiazole-2-carboxylic acid was found to slowly decarboxylate in solution at ambient temperature.

Key words

bicyclic compounds - heterocycles - benzothiazoles - benzothiazines - ring contraction - beetle luciferin

References

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