Sildenafil (formerly UK92480; UK-92480; Trade name: Revatio; VIAGRA), the free base form of Sildenafil, is a potent and selective inhibitor of phosphodiesterase type 5 (PDE5) with IC50 of 5.22 nM.

Siguazodan, also known as SKF 94836, is an orally active phosphodiesterase III (PDE-III) inhibitor.

ML-030 (CID-11757146) is a novel potent and selective PDE4 inhibitor with IC50 values of 6.7 nM, 12.9 nM, 48.2 nM, 37.2 nM, 452 nM and 49.2 nM for PDE4A, PDE4A1, PDE4B1, PDE4B2, PDE4C1,and PDE4D2, respectively.

Levosimendan (trade name Simdax) is a novel and potent calcium sensitizer that has been used in the management of acutely decompensated congestive heart failure.

Cilostamide (OPC3689) is a potent and highly selective inhibitor of type III phosphodiesterase (PDE3) (IC50s of 27 nM and 50 nM for PDE3A and PDE3B, respectively), it has antithrombotic and anti-intimal hyperplastic activity.

AMG 579 is a novel, potent, selective, and highly efficacious phosphodiesterase 10A (PDE10A) inhibitor with an IC50 of 0.1 nM.

DSR-141562 is a novel, potent, and selective brain-penetrant phosphodiesterase 1 (PDE1) inhibitor.

PF-04957325 (PF04957325) is a novel, highly potent and selective PDE8 inhibitor with important biological activity.

Eurycomanone could increases spermatogenesis by inhibiting the activity of phosphodiesterase and aromatase in steroidogenesis.

MBCQ is a novel, potent and selective cGMP-specific phosphodiesterase (PDE V; PDE5) inhibitor ( IC50 = 19 nM).