Synthetic and Biological Studies of Hemiketal E2 & Gaining Molecular Insight on the Synthesis of Nanoparticles

Abstract

Since the discovery that nonsteroidal anti-inflammatory drugs (NSAIDs) prevent pain, swelling, and inflammation by inhibiting the enzymes cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), there has been interest in anti-inflammatory drugs and their mechanisms. Arachidonic acid metabolites play an important role in many inflammatory diseases such as cancer, diabetes, asthma, and multiple sclerosis. Enzymatic metabolic pathways, like the transformation of arachidonic acid to prostaglandins or leukotrienes that utilize the enzymes COX-2 and 5-lipooxygenase (5-LOX) are physiologically relevant. Nonenzymatic pathways also exist, which involve reactive oxygen species (ROS) and ultimately lead to isoprostanes and isofurans. Unfortunately, arachidonic acid metabolites are not readily available. Specifically, newly discovered arachidonic acid metabolites, hemiketals D2 (HKD2) and E2 (HKE2) are only available in microgram quantities. Thus, in order to further elucidate the biological roles of HKD2 and HKE2 in the inflammatory response, a total synthesis is necessary. Understanding their roles could ultimately lead to the improvement of human health in preventing or treating various inflammatory diseases. & Modern bottom-up synthesis to nanocrystalline solid-state materials often lacks the reasoned product control that molecular chemistry boasts from having over a century of research and development. This systematic study demonstrates how rationally matching the reactivity of metal precursors to that of the main group precursor is necessary for the successful production of metal tellurides. Six transition metals including iron, cobalt, nickel, ruthenium, palladium, and platinum were reacted with the mild reagent didodecyl ditelluride in their acetylacetonate, chloride, bromide, iodide, and triflate salts. The first colloidal syntheses of iron and ruthenium tellurides (FeTe2 and RuTe2) are reported. Originally, Hard‒soft acid-base (HSAB) theory and lattice energies were used to explain these initial results, but upon analysis of the second and third-row metals this hypothesis failed. Thus, inquiries regarding the mechanistic implications of why certain metal telluride phases formed were explored, using metal triflate precursors, and radical stability was found to be a better predictor of reactivity.