The present invention relates to compounds of formula (I) or formula (II) or pharmaceutically acceptable salt, solvate or hydrate thereof, wherein said compound of formula (I) and said compound of formula II each comprises at least one ONO2 or ONO moiety; R1 is C1-C3alkyl; R2 is H, C1-C6alkyl, C3-C6cycloalkyl, C1-C2alkoxy, C2-C4alkenyl; R3 is C1-C4alkyl optionally substituted with C1-C2alkoxy, C3-C4cycloalkyl, C2-C4alkenyl; R4 and R5 are each independently H or C1-C6alkyl optionally substituted with F, OH, ONO, ONO2, COOH, C1-C3alkoxy, C3-C6cycloalkyl; or together with the nitrogen atom to which they are attached form a heterocyclic ring, wherein preferably said heterocyclic ring is selected from aziridine, azetidine, pyrollidine, piperidine, morpholine, piperazine, homo-piperazine, 2,5-diazabicyclo[2,2,1]heptane and 3,7-diazabicyclo[3,3,0]octane, wherein said heterocyclic ring is optionally substituted with independently one or more R6; R6 is C1-C6alkyl optionally substituted with independently one or more halogen, OH, ONO, ONO2, C1-C3alkoxy, C1-C3haloalkoxy, COOR7, NR8R9, C=NR10; R7 is H, or C1-C4alkyl optionally substituted with F, OH, ONO, ONO2, NR8R9; R8 and R9 are independently H, or C1-C4alkyl optionally substituted with ONO, ONO2; R10 is C1-C4alkyl optionally substituted with F, ONO, ONO2; C3-C6cycloalkyl; pharmaceutical compositions thereof, and their use in methods of treating or preventing a disease alleviated by inhibition of PDE5 in a human or in a non-human mammal.
