This is the Davut Paşa Mosque. The founder was Grand Vezir under Sultan Beyazit II. It has a very shallow dome, which is rightly praised in the guide Strolling through Istanbul; Redhouse. Also “the pendentives of the dome are an unusually magnificent example of the stalactite form, here boldly incised and brought far down the corners of the walls.” The guide complains a restoration is urgently needed, in 2006 I found it had been executed.