Discovery of indolizine lactones as anticancer agents and their optimization through late-stage functionalization.

Indolizines fused with a seven-member lactone ring were identified as a promising scaffold in the search for new anticancer agents. Through a modular synthetic sequence, a library of and indolizines lactones had their antiproliferative activity evaluated against hormone-refractory prostate DU-145 and triple-negative breast MDA-MB-231 cancer cell lines. A methoxylated analogue was identified as an initial hit against MDA-MB-231 and late-stage functionalization of the indolizine core led to analogues within potencies up to twenty times higher than the parent precursor.