The purpose is to provide a silicone compound which is well compatible with polymerizable silicone monomers and other polymerizable monomers to provide a polymer having high oxygen permeability, excellent hydrophilicity and anti-staining property, excellent dimension stability, and enough durability of mechanical strength not to deteriorate in a phosphate buffer solution. The other purpose is to provide a silicone compound having a high blocked terminal ratio and a high ratio of one specific structure and a method for preparing the silicone compound. The invention provides a compound represented by the following formula (1).Further, the invention provides a method for preparing the compound, use of the compound as an ophthalmic monomer, a polymer having repeating units derived from the aforesaid compound and an ophthalmic device composed of the polymer.
