Design, Synthesis, and Anti-Hepatic Fibrosis Evaluation of Cordycepin Derivatives

Activation of hepatic stellate cells (HSCs) featuring upregulated expression of α-smooth muscle actin (α-SMA) is recognized as a key driver for hepatic fibrosis, which provides a promising strategy for seeking anti-liver fibrogenic agents via suppressing the activation event. In this study, we designed and synthesized twenty-eight cordycepin derivatives through structural modifications at the C2 position and the C6-NH₂ group of the purine moiety. These compounds were screened for their inhibitory effects on HSC activation by detecting the mRNA expression of α-SMA using quantitative real-time polymerase chain reaction (qPCR) in the LX-2 cell model. Most compounds displayed inhibitory activity comparable to cordycepin, with compound <b>3a</b> bearing a C2-chloro and a N6-methyl-N6-(2-chlorobenzyl) substituent, demonstrating enhanced in vitro anti-fibrotic effect. This compound was able to dose-dependently downregulate α-SMA and collagen-I at both mRNA and protein levels, inhibited LX-2 cell migration, and exhibited improved metabolic stability in liver microsomes. The Western blotting result also indicated that <b>3a</b> could activate the AMPK signaling pathway. Overall, these results suggest <b>3a</b> may serve as a lead compound for further investigation.