On November 9th, 3675 Market Street will officially open its doors to the public about two years after its ceremonial groundbreaking. So far, the 14-story building is exactly what its partners — the Science Center, Cambridge Innovation Center (CIC), Wexford Science and Technology, BioLabs and Ventas — promised it would be, a 345,000 square foot mixed-use property that houses lab, clinical, office, educational, event and co-working space. The Science Center is relocating its headquarters there, leasing 50,000 square feet of the property, and the organization has even turned is ever-popular Quorum entrepreneur’s clubhouse into a two-story 15,000-square-foot hub that’s now accessible from the ground level.