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Octahedral Pt(IV) complexes ( 2Pt–R ) containing a glycoconjugate carbene ligand were prepared and fully characterized. These complexes are structural analogues to the trigonal bipyramidal Pt(II) species ( 1Pt–R ) recently described. Thus, an unprecedented direct comparison between the biological properties of Pt compounds with different oxidation states and almost indistinguishable structural features was performed. The stability profile of the novel Pt(IV) compounds in reference solvents was determined and compared to that of the analogous Pt(II) complexes. The uptake and antiproliferative activities of 2Pt–R and 1Pt–R were evaluated on the same panel of cell lines. DNA and protein binding properties were assessed using human serum albumin, the model protein hen egg white lysozyme, and double stranded DNA model systems by a variety of experimental techniques, including UV–vis absorption spectroscopy, fluorescence, circular dichroism, and electrospray ionization mass spectrometry. Although the compounds present similar structures, their in-solution stability, cellular uptake, and DNA binding properties are diverse. These differences may represent the basis of their different cytotoxicity and biological activity.

The growing concern about global warming and the consumption of fossil fuels has driven in recent decades the use of biomass as a renewable feedstock. In this context, vegetable oils, the corresponding fatty acids (FAs) and esters (FAEs) have primary importance: their esterification and transesterification lead to innovative products, that find application in several sectors, from biofuels to solvents, from surfactants to cosmetic ingredients and plasticizers. Lewis acid catalysis represents the most accredited methodology for developing processes of esterification and transesterification in line with sustainability requirements. The results available so far reveal the prevalent catalytic role of Zn(II) salts and coordination compounds, due to their beneficial eco-toxicological profile, combined with an appropriate acidity, finely tunable through selective functionalization. This review provides a picture of the state of the art in this important sector of biomass valorization. Roberto Esposito received his PhD in Chemical Sciences in 2018 at the University of Naples Federico II under the supervision of prof. F. Ruffo. He is researcher at the Department of Chemical Science of the University of Naples Federico II and his main research topics are W (VI), Zn(II) and Fe(III) based catalysts for conversion of biomasses and chemistry of tetra-coordinated and penta-coordinated complexes of Pt(II). Massimo Melchiorre graduated in Chemical Sciences in 2018. He is Board Member of ISusChem s.r.l., innovative start-up and university spin-off at the Dipartimento di Scienze Chimiche of the Università di Napoli Federico II. Company activity consists in biomass conversion and bio-based products development.

An unprecedented direct oxidation of high‐oleic triglycerides to produce azelaic glycerides has been carried out by using a catalytic system based on H2WO4/H2O2. The results are highly competitive with those reported so far for simpler feedstock: at low catalyst loading the oxidation proceeds with satisfactory yields also starting from a real waste oil matrix without any prior purification.

This work describes the use of simple zinc(II) salts (ZnCl 2 , ZnCO 3 , Zn(OAc) 2 , ZnO, Zn(ClO 4 ) 2 , Zn(TfO) 2 , and Zn(BF 4 ) 2 ) as effective catalysts for the esterification of fatty acids with long-chain alcohols and simple polyols through a homogeneous system that allows the gradual and selective removal of water. The results show that the catalytic activity depends on the nature of the counterion: the most effective are the salts with poorly coordinating anions (perchlorate and triflate) or containing basic Brønsted anions (oxide, acetate, and carbonate). However, only with the latter is it possible to fully recover the catalyst at the end of each run, which is easily filtered in the form of zinc carboxylate, given its insolubility in the ester produced. In this way, it is possible to recycle the catalyst numerous times, without any loss of activity. This beneficial prerogative couples the efficiency of the homogeneous catalysis with the advantage of the heterogeneous catalysis. The process is, therefore, truly sustainable, given its high efficiency, low energy consumption, ease of purification, and the absence of auxiliary substances and byproducts.