NPD-001 is an effective inhibitor of TbrPDEB1. NPD-001 is 10-fold more potent on hPDE4 (hPDE4B1 IC50 = 0.6 nM) than on TbrPDEB1 (IC50 = 4 nM).

Endo CNTinh-03 具有抑制作用，可阻止 cAMP 和 cGMP 通过 G 蛋白偶联受体、腺苷酸环化酶及鸟苷酸环化酶的激动剂而升高（IC50为 4 μM）。此外，该化合物能够抑制霍乱毒素与Escherichia coli(STa) 毒素导致的氯离子电流，有效改善小鼠分泌性腹泻的症状，并在多囊肾病模型中防止囊肿的形成。

Deltasonamide 2 is a competitive, high affinity PDEδ inhibitor with a Kd of ~385 pM.

PF-04449613 is a phosphodiesterase 9A (PDE9A) inhibitor (IC50= 22 nM).1It is selective for PDE9A over PDE1C (IC50= >1,000 nM), as well as over a variety of other PDEs, inhibiting PDE2-8, -10, and -11 activity by less than 30% in a panel of enzymes, ion channels, and transporters at 1 μM but does inhibit the human dopamine transporter (DAT; Ki= 293 nM). PF-04449613 (0.1-100 mg/kg, s.c.) increases cerebrospinal fluid (CSF) levels of cyclic GMP (cGMP) in rats. Subcutaneous administration of PF-04449613 (10 mg/kg) increases the rate of dendritic spine formation and elimination in mouse primary motor cortex pyramidal neuronsin vivo.2It increases the average running speed of mice in an accelerating rotarod task, indicating improved motor learning, at the same dose. 1.Claffey, M.M., Helal, C.J., Verhoest, P.R., et al.Application of structure-based drug design and parallel chemistry to identify selective, brain penetrant, in vivo active phosphodiesterase 9A inhibitorsJ. Med. Chem.55(21)9055-90

Pterine-6-carboxylic acid (6-Carboxypterin) 是叶酸的光降解产物，可被用作光敏感剂研究UVA 破环DNA 结构的分子机制。

Lirimilast（IC50 = 49 nM）是一种高效、选择性好且具有口服活性的磷酸二酯酶 4（PDE4）抑制剂 。Lirimilast具备显著的抗炎作用，可用于哮喘及慢性阻塞性肺疾病（COPD）相关研究。