Synthesis and factor Xa inhibitory activity of apixaban derivatives

Based on the current structure-activity relationship of apixaban, keeping P₁ portions unchanged and replace δ-valerolactam in P₄ portions with aromatic amide group, a series of dihydropyrazolopyridinones not reported were designed and synthesized. The structures of all the synthesized derivatives were identified by IR, ¹H NMR and MS. And then their anti-factor Xa activity was tested. The results showed that all the tested compounds exhibited factor Xa inhibitory activity, but with less potency than that of apixaban.