Connecting H bridge to micro-controller
You can't directly drive the PNP's with your microcontoller, as they would need 12V High signals to shut off.

Edit:
In response to your clarification, the pnp transistors are OFF when you set the base to 5V, and ON when you set the base to 0V.  You can tie the bases of A and B together, and control them with the same bit, and only one will be on at any given time.  Same with C and D.