Uh, no. Microsoft took the code and made it into Windows 1.0.Riiight. When Windows 1.0 came out in 1985, OS/2 was a baby not yet born.
Windows NT was a fresh code base developed by a team lead by one of the guiding lights behind the DEC VMS operating system.
Dave Cutler of VMS fame designed the kernel of Windows NT, but much of the middleware (including the bootloader and filesystem, as well as the design of the Win32 API) was taken away from OS/2. The desktop was a completely new design that was shared with Windows 3.1 at first, and then Windows 95 later.