Free radical scavenging and hepatoprotective effects of salidroside analogs on CCl 4 -induced cytotoxicity in LO2 cells

Salidroside, a phenylpropanoid glycoside isolated from a traditional Chinese medicinal plant Rhodiola rosea L. displays a broad spectrum of pharmacological properties. It has been found to play a hepatoprotective role in liver diseases through inhibiting apoptosis of hepatocytes and proliferation of hepatic stellate cells, decreasing serum aminotransferase, reversing hepatic fibrosis, and improving liver function. In this study as an ongoing study on the discovery and development of new hepatoprotective agents, about 12 novel glycosides were synthesized, and 2,2-diphenyl-1-picrylhydrazyl radical scavenge activity of each glycoside was evaluated. 2-(3,4,5-trihydroxyphenyl)ethyl β- d -glucopyranoside ( 4g ) and 2-(3,4,5-trihydroxyphenyl)ethyl β- d -galactopyranoside ( 4h ) exhibited significant activity prior to salidroside with an IC 50 value of 38.05 and 35.85 μM, respectively. The hepatoprotective effect of compounds 4g and 4h on CCl 4 -induced cytotoxicity in LO2 cells was assessed for further research. Graphical abstract 2-(3,4,5-Trihydroxyphenyl)ethyl β- d -glucopyranoside ( 4g ) and 2-(3,4,5-trihydroxyphenyl)ethyl β- d -galactopyranoside ( 4h ) exhibited significant hepatoprotective activity prior to salidroside.