Synthesis of a Coumarin-Based Analogue of Schweinfurthin F.

The natural schweinfurthins are stilbenes with significant antiproliferative activity and an uncertain mechanism of action. To obtain a fluorescent analogue with minimal deviation from the natural structure, a coumarin ring system was annulated to the D-ring, creating a new analogue of schweinfurthin F. This stilbene was prepared through a convergent synthesis, with a Horner-Wadsworth-Emmons condensation employed to form the central stilbene olefin.

Intramolecular Pyridinium Oxide Cycloadditions: Systematic Study of Substitution, Diastereoselectivity, and Regioselectivity.

Intramolecular pyridinium oxide cycloadditions form complex polycyclic nitrogenous architectures. The diastereoselectivity and regioselectivity of pyridinium oxide cycloadditions was systematically investigated for the first time using complex substrates. Predictably high levels of diastereoselectivity and regioselectivity are observed, which can be attributed to minimization of steric (syn-pentane) and torsional strain in the products.