Cardura
Doxazosin mesylate, a quinazoline compound sold by Pfizer under the brand name Cardura, is an alpha blocker used to treat high blood pressure and benign prostatic hyperplasia. It works by blocking the action of adrenaline on smooth muscle of the bladder and the blood vessel walls.
Its empirical formula is C23H25N5O5•CH4O3S, and it has a molecular weight of 547.6.