Design and Synthesis of Novel Quinoline Tethered Tricyclic 1,5-Benzothiazepine Derivatives via 1,3-Dipolar Cycloaddition Reaction

A series of novel substituted-[1,2,4] oxadiazolo[5,4-d][1,5] benzothiazepine derivatives contain quinoline ring 5a-5l were synthesized by the reaction of benzothiazepines 4a-4c and substituted-benzohydroximinoyl chlorides through the 1,3-dipolar cycloaddition reaction in the presence of Et3N at room temperature. The structures of the obtained adducts were elucidated by MS, IR, H-1 NMR, and elemental analyses. In addition, the structures of 5e were further confirmed by X-ray single crystal diffraction study.