Synthesis and crystal structure of novel [1,2,4]oxadiazolo[5,4‐d][1,5]benzothiozepine derivatives containing pyrazole moiety

A series of new substituted‐1,2,4]oxadiazolo5,4‐d]1,5]benzothiazepine derivatives containing pyrazole ring 4 / 4′ was synthesized by substituted‐pyrazolo1,5]benzothiazepines 2 / 2′ and substituted‐benzohydroximinoyl chlorides 3 through the 1,3‐dipolar cycloaddition reaction in the presence of Et₃N at room temperature, and characterized by MS, IR, ¹H NMR and elemental analyses. In addition, the structure of 4′l was determined by X‐ray crystallography. J. Heterocyclic Chem., 2011.