The introduction of biomass-derived compounds as an alternative feed into the refinery structure that already exists can potentially converge energy uses with ecological sustainability. Herein, we present an approach to produce a bio-oil based on carbohydrate-derived isopropylidene ketals obtained by reaction with acetone under acidic conditions directly from second-generation biomass. The obtained bio-oil showed a greater chemical inertness and miscibility with gasoil than typical bio-oil from fast pyrolysis. Catalytic upgrading of the bio-oil over zeolites (USY and Beta) yielded gasoline with a high octane number. Moreover, the co-processing of gasoil and bio-oil improved the gasoline yield and quality compared to pure gasoil and also reduced the amount of oxygenated compounds and coke compared with pure bio-oil, which demonstrates a synergistic effect.

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Human kallikrein 5 (KLK5) and 7 (KLK7) are potential targets for the treatment of skin inflammation and cancer. Previously, we identified isomannide derivatives as potent and competitive KLK7 inhibitors. The introduction of Nprotected amino acids into the isomannide-based scaffold was studied. Some KLK5 inhibitors with submicromolar affinity (K i values of 0.3−0.7 μM) were identified, and they were 6-to 13-fold more potent than our previous hits. Enzyme kinetics studies and the determination of the mechanism of inhibition confirmed that the new isomannide-based derivatives are competitive inhibitors of both KLK5 and KLK7. Molecular docking and MD simulations of selected inhibitors into the KLK5 binding site provide insight into the molecular mechanism by which these compounds interact with the enzyme. The promising results obtained in this study open new prospects on the design and synthesis of highly specific KLK5 and KLK7 inhibitors.

Sugar cane biomass is a rich and powerful source of carbon atoms for renewable fuel generation. However, its efficient introduction into the standard refinery installations is still a challenge. Recently, we have shown the possibility to produce gasoline compounds through refinery-friendly biocrudes obtained by one-pot hydrolysis−ketalization reaction of second-generation sugar cane biomass. Herein, we describe the development and validation of a liquid chromatography−triple quadruple mass spectrometry (LC−MS/MS) method to quantify four carbohydrate-derived O-isopropylidene ketals present in biocrudes obtained by different reaction conditions and also the identification of six other compounds based on MS/MS fragmentation experiments. The validated method was selective, precise, accurate, and linear over the range of 0.2−25 μg mL −1 , with correlation coefficient values higher than 0.99. The reaction carried out at 90 °C for 3 h resulted in a biocrude with 34.2% (w/w) of biomass conversion and 38.1% formation of the monitored O-isopropylidene ketals, with xylose diacetonide being the most abundant and rapidly formed compound. In addition, disaccharides of pentose and pentose−hexose containing from one to three O-isopropylidene units have been identified. This LC−MS/MS analysis permitted a better understanding of the chemical composition of biocrudes and, therefore, could remarkably improve the possibility of tailor-made biocrudes in function of the regular refinery process.