New orally active PDE4 inhibitors with therapeutic potential Original Research Article

The design, synthesis, and biological evaluation of a series of pyrazolopyridines was carried out. Structural optimization of the aniline moiety of 4-anilinopyrazolopyridine derivative 3a, which is one of the newly discovered chemical leads for PDE4 inhibitors from our in-house library, was performed successfully. The details of the discovery of new orally active PDE4 inhibitors, which are expected to show therapeutic potential, are presented and their structure–activity relationships are discussed. Pharmacological evaluation and pharmacokinetic data for representative compounds are also presented.