abstract |
There is provided a general formula (I) or a pharmaceutically or veterinarily acceptable salt or polymorph and/or solvate thereof, wherein R1 represents H; C(O)C¿1?-C4 alkyl; C(O) aryl; C(O)heteroaryl. And which is useful in the curative and prophylactic treatment of a medical condition for which inhibition of a cyclic guanosine 3',5'-monophosphate phosphodiesterase (and in particular cGMP PDE5) is desired. |