Pharmaceutically active compounds

Abstract

There is provided a general formula I: 1 or a pharmaceutically or veterinarily acceptable salt or polymorph and/or solvate thereof, wherein R1 represents H; C(O)C1-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.

Dependencies are inferred from the claim text.