Can this drain pipe service two bathroom sinks?
I can't speak to code, but what you'll want is a sanitary cross, or sanitary tee to do this. It should be legal in most areas.

The real trick here is you really need some way to allow air in. The best solution is to cut a wye or tee into the main stack further up and run pipe up back down into the new sanitary tee for your sink drains. If you can't do that, it should be acceptable to put an air admittance valve into the wall and add a vented access panel on one side (they should have had one on the sink you removed).

From this PDF