The asymmetric unit of the title compound, C(30)H(27)N(2)O(4)PS(2), consists of two crystallographically independent mol-ecules. The thieno[2,3-b]thio-phene ring systems are planar. One of the terminal ethyl groups is disordered over two positions; the site occupancy factors are ca 0.7 and 0.3. The crystal structure is stabilized by N-H⋯N, N-H⋯O and C-H⋯O hydrogen bonds.