The title compound（C25H16Cl2N3O3S）,as a thiopyran derivative,has been synthe-sized by the cyclization of an organic intermediate obtained from Baylis-Hillman adducts with a β-aroylthioamide using copper（I） salt as the catalyst.The crystal belongs to the monoclinic system,space group P21/c with a = 13.668（3）,b = 8.4803（17） c = 21.999（4） ,β = 113.57（3）°,V = 2337.2（10） 3,Z = 4,Mr = 510.38,Dc = 1.451 g/cm3,μ = 0.401 mm-1,F（000） = 1048,the final R = 0.0487 and wR = 0.1079 for 3678 observed reflections with I〉 2σ（I）.
The title compound （C19H17BrN2O4） was synthesized via a one-pot procedure starting from 4-bromobenzaldehyde, dimethyl acetylenedicarboxylate （DMAD） and phenylhydrazine with pyridine as the catalyst. Its structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 11.115（3）, b = 8.090（2）, c = 20.211（5） , β = 97.032（5）°, V = 1803.7（8） 3, Z = 4, Mr = 417.25, Dc = 1.536 g/cm3, μ = 2.306 mm-1, F（000） = 852, the final R = 0.0403 and wR = 0.0895 for 2215 observed reflections with I 2σ（I）.
