PDE4B-IN-6 (compound 4i) is a potent and selective PDE4B inhibitor with an IC50 of 7.42 nM. PDE4B-IN-6 shows ~195- and ~169-fold selectivity for PDE4B over PDE4A (IC50 = 1540 nM) and PDE4C (IC50 = 1260 nM), respectively. PDE4B-IN-6 increases cAMP level and suppresses TNF-α expression. PDE4B-IN-6 shows favorable antioxidant profiles and low cytotoxicity. PDE4B-IN-6 can be used for chronic obstructive pulmonary disease (COPD) research[1].
