Abstract
Structure-activity relationship studies on oleanolic acid (
) have resulted in facile syntheses of its new C-28 esters
by way of one-pot reaction of
with a variety of alkylating agents. Oleanolic acid and its new esters were studied for their in vitro antiproliferative effect on healthy human peripheral blood mononuclear cell isolated phytohemagglutinin activated T cells. Results showed that compounds
,
, and
exhibited significant inhibitory activity on T-cell proliferation. Compound
was found to be the most potent, with an IC
value of 4.249 μg/mL, among all tested compounds, and its activity could be attributed to the presence of bromine atom in the molecule.