。
The pharmacy is at the end of this road.
Literal
Pharmacy [topic-は] this road [gen-の] dead-end [loc-に] exists.
突き当たり literally 'the place of striking against,' i.e., where a road terminates and you can't go further — the T-intersection or dead-end at the far end. 薬屋 is the older colloquial word for a pharmacy (lit. 'medicine shop'), a touch less formal than 薬局. あります is the standard polite locative existence verb for inanimate things.