The asymmetric unit of the title compound, C(21)H(20)N(4)O(3)S, contains two independent mol-ecules. The dihedral angles between the two benzene rings are 47.6 (1) and 30.2 (1)°, the corresponding values between the p-methoxy-benzene and thia-diazol rings are 12.3 (1) and 24.7 (1)°, respectively, for the two mol-ecules. The conformations of the N-H and C=O bonds are anti with respect to each other. The enone groups show a trans configuration. The crystal structure is stabilized by N-H⋯O and N-H⋯N inter-actions. The absolute structure could not be determined from the X-ray data but the absolute configuration has been assigned by reference to an unchanging chiral centre in the synthetic procedure.