New acetylenic derivatives of betulin and betulone, synthesis and cytotoxic activity.

Betulin and its semisynthetic derivatives exhibit a cytotoxic activity toward various cancer cell lines. These compounds are a promising and potential anticancer candidates. A series of betulin derivatives was prepared and tested for the antiproliferative activity in vitro against T47D breast cancer, CCRF/CEM leukemia, HL-60 promyelocytic leukemia, SW707 colorectal, murine P388 leukemia, as well as BALB3T3 normal fibroblasts cell lines. Cisplatin and betulin were used as a reference compounds. Some derivatives of betulin showed a higher cytotoxic activity than the parent compound . Two derivatives ( and ) were 24-fold potent than betulin against the human promyelocytic leukemia cell line (HL-60), with an IC value of 0.3 µg/mL.