Synthesis and differential antiproliferative activity of Biginelli compounds against cancer cell lines: Monastrol, oxo-monastrol and oxygenated analogues.

The synthesis and differential antiproliferative activity of monastrol (1a), oxo-monastrol (1b) and eight oxygenated derivatives 3a,b-6a,b on seven human cancer cell lines are described. For all evaluated cell lines, monastrol (1a) was shown to be more active than its oxo-analogue, except for HT-29 cell line, suggesting the importance of the sulfur atom for the antiproliferative activity. Monastrol (1a) and the thio-derivatives 3a, 4a and 6a displayed relevant antiproliferative properties with 3,4-methylenedioxy derivative 6a being approximately more than 30 times more potent than monastrol (1a) against colon cancer (HT-29) cell line.