Synthesis of peptides based on betulinic acid scaffold and betulinic-butyrolactone derivatives / Habsah Zahari

Several Betulinic acid peptides here synthesized by incorporating BA with neutral amino acids using standard coupling protocols in the presence of HoBt, HBtu and DiPEA. In addition enantiopure betulinic-acid- cyclohexene silyl ether peptides was successly synthesized in a good yield. Futher olefinic cleavage reaction, afforded betulinic acid -y- butylrolactone peptides, which undergoes benzylation reaction to furnish desired end product benzylated BA-y-butylrolactone product. Five new synthesized betulinic acid derivatives were tested for their in vitro cytotoxicity against human corrected carainoma cell lines ( HT116). The result of preliminary biological activities showed that three compounds betulinic acid-cyclohexene silyl ether peptides, benzylated betulinic acid-alanine peptide, and benzylated betulinic acid-y-butylrolactone peptides with more hydrosolubility compare to betulinic acid, possessed impressive cytotoxicity with the IC50 values of 50.00, 36.67, 25.33 (ug/ml) respectively