Preparation of betulinic acid derivatives by chemical and biotransformation methods and determination of cytotoxicity against selected cancer cell lines

Several novel 2,4-dinitrophenylhydrazone betulinic acid derivatives have been prepared by chemical and biotransformation methods using fungi and carrot cells. Some compounds showed significant cytotoxicity and selectivity against some tumor cell lines. The most active, 3-[(2,4-dinitrophenyl)hydrazono]lup-(20R)-29-oxolupan-28-oic acid, showed IC50 values between 1.76 and 2.51 μM against five human cancer cell lines. The most selective, 3-hydroxy-20-[(2,4-dinitrophenyl)hydrazono]-29-norlupan-28-oic acid, was five to seven times more selective for cancer cells when compared to fibroblasts. Cell cycle analysis and apoptosis induction were studied for the most active derivatives. [Display omitted] •Betulinic acid (BA) derivatives were synthesized or obtained by biotransformation.•Cytotoxicity and selectivity towards 5 human cancer cell lines were investigated.•Compounds 4 and 5, aldehyde of 2,4-DNPH BA, were the most cytotoxic derivatives.•The tested compounds showed to be more selective toward human tumor cell lines.•Compound 4 induces apoptosis in human lung cancer A549 cells.