Phosphoramidate Derivatives of Betulin, New Molecules with Promising Biological Activity: Synthesis and Characterization

Studies of natural products and their semisynthetic derivatives are a valuable source of therapeutic agents. The aim of this work was to obtain new 30-phosphoramidate derivatives of betulin and determine their biological potential. The synthetic approach utilized the Staudinger reaction (the introduction of a phosphoramidate group), the Steglich reaction (the introduction of an alkynyl group), and the Jones reaction (the introduction of a carboxyl group). The structures of the target compounds were determined using spectroscopic methods (¹H NMR, ¹³C NMR, ³¹P NMR, and HRMS). The new derivatives were tested for antiproliferative activity against MV4-11, A549, MCF-7, PC-3, and HCT116 cancer cells and against normal MCF-10A cells using the MTT and SRB methods. Apoptosis studies were performed for the most active compounds (<b>6B</b> and <b>7A</b>), potential molecular targets (AutoDock software) were identified, and lipophilicity parameters (RP-TLC method, SwissADME website) were determined. The greatest effect on apoptosis and caspase 3/7 activation was observed for the diester derivative <b>7A</b>. Compound <b>7A</b> showed a high lipophilicity parameter in the study group.