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Ionic liquids are used in various fields due to their unique physical properties and are widely utilized as reaction solvents in the field of synthetic organic chemistry. We have previously proposed a new organic synthetic method in which the catalyst and reaction reagents are supported on ionic liquids. This method has various advantages, such as the ability to reuse the reaction solvent and catalyst and its facile post-reaction treatment. In this paper, we describe the synthesis of an ionic liquid-supported anthraquinone photocatalyst and the synthesis of benzoic acid derivatives using this system. This synthesis of benzoic acid derivatives via the cleavage of vicinal diols by an ionic liquid-supported anthraquinone photocatalyst is an environmentally friendly process, and furthermore, it has a simple post-reaction process, and the catalyst and solvent can both be reused. To the best of our knowledge, this is the first report on the synthesis of benzoic-acid derivatives via the cleavage of vicinal diols using light and an ionic-liquid-supported catalyst.

Background: Bortezomib (BTZ), a primary treatment for MM, but its effectiveness can be reduced by interactions with vicinal diol moieties (VDMs) in polyphenols. Despite this, it’s debated whether BTZ therapy necessitates avoiding polyphenol-rich products, given the low bioavailability of polyphenols. Additionally, it remains unclear whether the structure of polyphenols contributes to their BTZ antagonism. Therefore, our study aims to unravel the structure-activity relationship of dietary polyphenols and their BTZ antagonism at daily diet-achievable physiological concentrations. Methods: We assessed the antagonistic effects of 25 polyphenols against BTZ using cell viability assays in RPMI 8226 cells. ChemGPS-NP helped analyze the structural similarity. Additionally, long-term cytotoxicity assays evaluated these effects at physiologically relevant concentrations. Results: By cell viability assays, we found a positive correlation between the number of VDMs in gallotannins and their BTZ antagonism. Moreover, the origin and configuration of VDMs, rather than the total VDM concentration, play a pivotal role in the combined antagonistic effects against BTZ in gallotannins. Additionally, ChemGPS-NP analysis indicated that the aromaticity and C-3 hydroxyl group in flavonoids’ C-rings enhance their BTZ antagonism. Finally, long-term cytotoxicity assays reveal that gallic acid (GA), epigallocatechin (EGC), and epigallocatechin gallate (EGCG), at their physiological concentrations—attainable through tea consumption—significantly and synergistically antagonize BTZ. Conclusion: Due to the potential for these polyphenols to reduce the effectiveness of BTZ, it is advisable for MM patients undergoing BTZ treatment to reduce their consumption of foods high in VDM-containing polyphenols.

Epoxide hydrolases (EHs) are present in all living organisms. They have been extensively characterized in mammals; however, their biological functions in plants have not been demonstrated. Based on in silico analysis, we identified AtEH1 (At3g05600), a putative Arabidopsis thaliana epoxide hydrolase possibly involved in cutin monomer synthesis. We expressed AtEH1 in yeast and studied its localization in vivo. We also analyzed the composition of cutin from A. thaliana lines in which this gene was knocked out. Incubation of recombinant AtEH1 with epoxy fatty acids confirmed its capacity to hydrolyze epoxides of C18 fatty acids into vicinal diols. Transfection of Nicotiana benthamiana leaves with constructs expressing AtEH1 fused to enhanced green fluorescent protein (EGFP) indicated that AtEH1 is localized in the cytosol. Analysis of cutin monomers in loss-offunction Ateh1-1 and Ateh1-2 mutants showed an accumulation of 18-hydroxy-9,10-epoxyoctadecenoic acid and a concomitant decrease in corresponding vicinal diols in leaf and seed cutin. Compared with wild-type seeds, Ateh1 seeds showed delayed germination under osmotic stress conditions and increased seed coat permeability to tetrazolium red. This work reports a physiological role for a plant EH and identifies AtEH1 as a new member of the complex machinery involved in cutin synthesis.

Vicinal diols are important signaling metabolites of various inflammatory diseases, and some of them are potential biomarkers for some diseases. Utilizing the rapid reaction between diol and 6-bromo-3-pyridinylboronic acid (BPBA), a selective and sensitive approach was established to profile these vicinal diols using liquid chromatography-post column derivatization coupled with double precursor ion scan-mass spectrometry (LC-PCD-DPIS-MS). After derivatization, all BPBA-vicinal-diol esters gave a pair of characteristic isotope ions resulting from 79Br and 81Br. The unique isotope pattern generated two characteristic fragment ions of m/z 200 and 202. Compared to a traditional offline derivatization technique, the new LC-PCD-DPIS-MS method retained the capacity of LC separation. In addition, it is more sensitive and selective than a full scan MS method. As an application, an in vitro study of the metabolism of epoxy fatty acids by human soluble epoxide hydrolase was tested. These vicinal-diol metabolites of individual regioisomers from different types of polyunsaturated fatty acids were easily identified. The limit of detection (LOD) reached as low as 25 nM. The newly developed LC-PCD-DPIS-MS method shows significant advantages in improving the selectivity and therefore can be employed as a powerful tool for profiling vicinal-diol compounds from biological matrices.

ObjectivesTo investigate the efficiency of a new cascade biocatalysis system for the conversion of R, S-β-amino alcohols to enantiopure vicinal diol and β-amino alcohol.ResultsAn efficient cascade biocatalysis was achieved by combination of a transaminase, a carbonyl reductase and a cofactor regeneration system. An ee value of > 99% for 2-amino-2-phenylethanol and 1-phenyl-1, 2-ethanediol were simultaneously obtained with 50% conversion from R, S-2-amino-2-phenylethanol. The generality of the cascade biocatalysis was further demonstrated with the whole-cell approaches to convert 10–60 mM R, S-β-amino alcohol to (R)- and (S)-diol and (R)- and (S)-β-amino alcohol in 90–99% ee with 50–52% conversion. Preparative biotransformation was demonstrated at a 50 ml scale with mixed recombinant cells to give both (R)- and (S)-2-amino-2-phenylethanol and (R)- and (S)-1-phenyl-1, 2-ethanediol in > 99% ee and 40–42% isolated yield from racemic 2-amino-2-phenylethanol.ConclusionsThis cascade biocatalysis system provides a new practical method for the simultaneous synthesis of optically pure vicinal diol and an β-amino alcohol.

In this study, a 4-vinylphenylboronic acid-functionalized graphene oxide (GO) material was prepared via atom-transfer radical polymerization (ATRP) method and applied for the first time as a novel matrix for the selective enrichment and analysis of small-molecule compounds with vicinal diols, which have been the focus of intense research in the field of life science, by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) in positive-ion mode. There are two main factors playing a decisive role in assisting laser D/I process comparing to some traditional matrices: (1) GO provides π-conjugated system by itself for laser absorption and energy transfer; (2) the modified 4-vinylphenylboronic acid can selectively capture small-molecule compounds with vicinal diols. The results demonstrate that the novel material has distinct advantages over previously reported matrices in enriching and assisting the highly efficient ionization of target molecules for mass spectrometry analysis. This work indicates a new application branch for graphene-based matrices and provides an alternative solution for small-molecules analysis. Graphical Abstract ᅟ

The γ-radiation-induced transformations of α-diols in deaerated aqueous solutions at pH 7 have been studied. The composition and radiation-chemical yields of the main products of their radiolysis were determined. It has been established that dehydration by a chain mechanism is a characteristic process for α‑diols with terminal positions of hydroxyl groups (1,2-propanediol and 1,2-butanediol). In the radiolysis of an α-diol with the central arrangement of hydroxyl groups (2,3-butanediol), chain processes did not occur: dehydration and destruction of the diol via C–C bond scission occurred with approximately equal probabilities. The observed effects were explained, and the importance of the obtained results for studying the mechanisms of free-radical fragmentation reactions of hydroxyl-containing biomolecules induced by ionizing radiation was stated.

Michael adduct of levoglucosenone and cyclohexanone, 1,6-anhydro-3,4-dideoxy-4- C -(2-oxocyclohexan-1-yl)-β-D-erythrohexo-2-ulose, was treated with ethylene glycol in the presence of oxalic acid, and the resulting mixed ketal, 2-{(4a′ S ,6a′ S ,10a′ R ,10b′ R )-octahydrospiro[1,3-dioxolane-2,2′-pyrano[2,3- c ]chromen]-6a′(1′H)-yloxy}ethanol, was used a chiral auxiliary in the synthesis of vicinal diols.

Nowadays, a new approach to the synthesis of glycerol-free biodiesel is being developed in the framework of sub- and supercritical fluid (SCF) technologies, which is based on the use of supercritical ethanol as an active medium for the transesterification of triglycerides. This approach involves in situ lipophilization of the liberated glycerol to give products compatible with the biodiesel medium. To get an insight into the mechanism of this process, the transformations of supercritical ethanol itself have been studied. Samples of ethanol obtained after supercritical fluidization have been found to contain a set of compounds interrelated through redox and condensation reactions, starting from acetaldehyde diethyl acetal. The latter, as well as its higher homologs, could trap glycerol and convert it to lipophilized products. A number of new reactions have been revealed, and compounds specific for supercritical fluid conditions have been identified.

Terminal vicinal diols are important chiral building blocks and intermediates in organic synthesis. Reduction of α‐hydroxy ketones provides a straightforward approach to access these important compounds. In this study, it has been found that asymmetric reduction of a series of α‐hydroxy aromatic ketones and 1‐hydroxy‐2‐pentanone, catalyzed by Candida magnolia carbonyl reductase (CMCR) with glucose dehydrogenase (GDH) from Bacillus subtilis for cofactor regeneration, afforded 1‐aryl‐1,2‐ethanediols and pentane‐1,2‐diol, respectively, in up to 99 % ee. In order to evaluate the efficiency of the bioreduction, lyophilized recombinant Escherichia coli whole cells coexpressing CMCR and GDH genes were used as the biocatalyst and α‐hydroxy acetophenone as the model substrate, and the reaction conditions, such as pH, cosolvent, the amount of biocatalyst and the presences of a cofactor (i.e., NADP+), were optimized. Under the optimized conditions (pH 6, 16 h), the bioreduction proceeded smoothly at 1.0 m substrate concentration without the external addition of cofactor, and the product (S)‐1‐phenyl‐1,2‐ethanediol was isolated with 90 % yield and 99 % ee. This offers a practical biocatalytic method for the preparation of these important vicinal diols. Self‐sufficient catalysis! Lyophilized recombinant Escherichia coli coexpressing Candida magnolia carbonyl reductase (CMCR) and glucose dehydrogenase (GDH) genes served as an effective self‐sufficient biocatalyst for the reduction of α‐hydroxy acetophenones at high substrate concentrations. The products were isolated with high yield and excellent optical purity, offering a practical biocatalytic method for the preparation of vicinal diols.