Two years ago the building where I rent office space changed owners. I was told that the original lease would be honored. I want to know if I can leave even though I still have 2 years left on lease? I never signed anything with new owners. This is in New York.

Unless your lease specifically gives you the right to cancel the lease if the building changes ownership, which is very unlikely, you are still obligated to the terms of the lease. It wasn't necessary for you to sign anything with the new owners. Your lease was assigned from the former owner to the current owner.