A Structure-Activity Relationship Study of Amino Acid Derivatives of Pterostilbene Analogues Toward Human Breast Cancer.

Pterostilbene is the dimethylated analogue of Resveratrol, a compound with well-known biological activities, such as antioxidant, chemopreventive, anti-diabetic, anti-obesity, and cardioprotective. Despite many studies on the general effect of such polyphenolic molecules and their derivatives, a deep comprehension of their action and systematic structure-activity relationship studies are still rare. Herein, three different analogues of functionalizable Pterostilbene were efficiently synthesized and derivatized with a selected library of antioxidant amino acids, allowing for a highly diversified exploration of the chemical space. The library was analyzed towards cancer cells. Collectively, our data demonstrated the enhanced anti-proliferative activity of Tryptophan-conjugated compounds. In breast cancer cells, the treatment with Tryptophan-conjugated analogues induced the activation of cellular stress pathways, including autophagy signaling.

A LC-QTOF Method for the Determination of PEGDE Residues in Dermal Fillers.

Hyaluronic acid is one of the most important ingredients in dermal fillers, where it is often cross-linked to gain more favorable rheological properties and to improve the implant duration. Poly(ethylene glycol) diglycidyl ether (PEGDE) has been recently introduced as a crosslinker because of its very similar chemical reactivity with the most-used crosslinker BDDE, while giving special rheological properties. Monitoring the amount of the crosslinker residues in the final device is always necessary, but in the case of PEGDE, no methods are available in literature. Here, we present an HPLC-QTOF method, validated according to the guidelines of the International Council on Harmonization, which enables the efficient routine examination of the PEGDE content in HA hydrogels.