When heated, phenyl pyridin-2-ylcarbamate (1) decomposes to 2-isocyanatopyridine (2) which reacts with the heterocyclic compound (3) to give droxicam.[2][3][4]
References
^Jané F, Rodríguez de la Serna A (1991). "Droxicam: a pharmacological and clinical review of a new NSAID". European Journal of Rheumatology and Inflammation. 11 (4): 3–9. PMID1365488.
^US patent 4563452, Jose M. Ribalta-Baro and Jordi F. Rigola-Constansa, "Benzothiazine derivatives and their applications as medicinal products or as synthesis intermediates for medicinal products", issued 1992-07-21, assigned to Laboratorios del Dr Esteve SA