A two-dimensional network Compound, [{Mn(saltmen)}(4)-{Co(CN)(6)}](ClO4)center dot 9H(2)O (2) (saltmen(2-) = N,N'-(1,1,2,2-tetramethylethylene)bis(salicylideneiminate)), was synthesized. Magnetic measurements characterized the [Mn-2(saltmen)(2)](2+) Subunit its it single-molecule magnet with an S-T = 4 spin ground state, indicating that the Mn-III dinier is magnetically isolated not only by the diamagnetic [Co(CN)(6)](3-) Unit but also by the space between the layers.