Azetidinone-retinoid hybrids: Synthesis and differentiative effects.

As a part of a systematic investigation on the synthesis and biological activities of new β-lactam compounds, we examined β-lactam candidates 1, 2E and 2Z and their ability to induce cell proliferation or differentiation. Azetidinone 1 was chosen for its activity (previously evaluated) as selective HDAC8 inhibitor, whereas β-lactams 2E and 2Z were designed to have a hybrid retinoid-azetidinone structure, de novo synthesized and fully characterized. Biological activities were determined in cellular assays on neuroblastoma cells SH-SY5Y. Azetidinone 1, 2E and 2Z led to a moderate effect in decreasing SH-SY5Y cell proliferation and β-lactams 2E and 2Z induced an early stage differentiation. The present results uncovered a new role of specifically designed β-lactam compounds in epigenetic regulation.