Reaction of [Fe(bpy)3]Cl2 upon [MS4Cu4Cl4]2− (MMo, W) anions in acetonitrile-dichloromethane mixture gave incomplete cubanes. In the case of tungsten, [WS3.4O0.6Cu3(bpy)2Cl] (2a) was obtained and structurally characterized; orthorhombic, Pcab, a=13.942(9), b=10.415(3), c=33.739(4) Å, V=4893(3) Å3, Z=8, R=0.059 and Rw=0.064. The overall geometry of 2a is described as a cubane with a missing chloro-corner. Two copper atoms are tetrahedrally bound each of them being ligated to two sulfur and one bipyridine. The third copper has a trigonal environment, two sulfur atoms and a terminal chlorine. An oxygen-sulfur mixed occupancy was introduced for the terminal WS bond, supported by IR data. In the molybdenum analogue 2b the terminal double bond is pure MoO since the formula of 2b is [MoOS3Cu3(bpy)2Cl]. The product of oxidation of [Febpy)3]Cl2 found in the course of the preparation of 2a was characterized as [Fe(bpy)3][Fe2OCl6] (1) by X-ray structure determination. The products of oxidation of copper(I) led to [Cu(bpy)2]2[MS4Cu3Cl3]·CH3CN, MW (3a), a=13.854(2), b=16.452(2), c=22.072(4) Å, β=97.06(1)°, Z=4, and MMo (3b), a=13.886(7), b=16.451(4), c=22.054(15) Å, β=96.84(5)°, Z=4, which were also characterized by X-ray structure determination.