Coordination complexes, [Cu-2(H2L)(bpy)(2)].2H(2)O, (1a), [Cu(H3L)(2) (H2O)(4)].(H(2)bpypa)(2).6H(2)O, (2a) and [Cu(H3L)(4)] [Cu(H2O)(6)].(H(2)bpypa)(4).20H(2)O, (2b), of mellitic acid, H6L, with 4,4'-bipyrdine, (bpy), and 1,3-bis(4-pyridyl) propane, (bpypa), have been prepared and the three-dimensional structures are established by single crystal X-ray diffraction unequivocally. The complex 1a was prepared following hydrothermal method, while the complexes 2a and 2b were obtained concomitantly from an aqueous solution at room temperature. In the crystals of 1a, both acid and the aza-donors form coordination bonds with metal ions, while in 2a and 2b coordination bonding prevails between metal and acid molecules only, with azadonor molecules remain intact without coordinating to metal species. Further, 1a and 2b are noted to be yielding a hostguest network, whereas 2a forms planar sheets that are stacked in three-dimensional arrangemen