Background: Boronic acids form di-ester bonds with cis-hydroxyl groups in carbohydrates. The formation of these adducts could impair the physical and chemical properties of the precursors, even their biological activity. Methods: Two carbohydrate-derivatives from D-fructose and D-arabinose and phenylboronic acid were synthesized in a straightforward one-step procedure and chemically characterized by spectroscopy and X-ray diffraction crystallography. Also, an acute toxicity test was performed to determine their Lethal Dose50 (LD50) by using the Lorke’s method. Results: Analytical chemistry assays confirmed adducts by the generation of the diester bonds with a β-D-pyranose of carbohydrates, including signals corresponding to the formation of new bonds, like the stretching of B-O bonds. The NMR spectra yielded information about the stereoselectivity in the synthesis reaction by the finding of just one signal in the range for the anomeric carbon in the 13C NMR spectra of both adducts. The acute toxicity tests showed that LD50 value for both compounds is 1265 mg/kg, while Effective Dose 50 for sedation is 531 mg/kg. However, differences were in the onset and lapse of sedation. Conclusions: These adducts are bioactive and highly safe agents. Further biological evaluation is desirable to explore medical purposes.

Abstract: Formation of DNA adducts is a key event for a genotoxic mode of action and its formation is often use as surrogate for mutation and cancer. Interest in DNA adducts are twofold, first, to demonstrate exposure, and second, to link DNA adduct location to subsequent mutations or altered gene regulation. High chemically specific mass spectrometry methods have been established for DNA adduct quantitation and elegant bio-analytic methods utilizing enzymes, various chemistries, and molecular biology methods to visualize the location of DNA adducts. Traditionally, these highly specific methods cannot be combined, and the results are incomparable. Initially developed for single-molecule DNA sequencing, nanopore-type technologies are expected to enable simultaneous quantitation and location of DNA adducts across the genome. We will briefly summarize the current methodologies for state-of-the-art quantitation of DNA adduct levels and mapping of DNA adducts and describe novel single-molecule DNA sequencing technology that is expected to achieve both measures simultaneously. Emerging technologies are expected to soon provide a comprehensive picture of the exposome and identify gene regions susceptible to DNA adduct formation.

Dubermatinib (DMB, TP-0903), a benzenesulfonamide, is an inhibitor of the tyrosine kinase AXL, which is a member of the TAM family, and can prevent GAS6-mediated activation of AXL in cancer cells. Patients with previously treated chronic lymphocytic leukemia are being studied in phase I/II clinical trials to determine its antineoplastic potential (CLL). In the current work, the reactive intermediates of DMB were studied using liquid chromatography-mass spectrometry (LC-MS). Human liver microsomes (HLMs) were exposed to dimethylbenzene in a laboratory setting, and the resulting metabolites were collected through protein precipitation. Intense reactivity toward nucleophilic macromolecules was seen in the metabolites of the piperazine and pyrimidine rings in DMB, iminium and 2,5-quinone-imine, respectively. To assess the toxicities of the possibly reactive metabolites, DMB was incubated with HLMs in the presence of 1.0 mM KCN and 1.0 mM glutathione. The DMB metabolites found by LC-MS/MS were seven in vitro phase I metabolites, three cyano adducts, and two GSH conjugates. Phase I in vitro metabolic reactions included N-demethylation, hydroxylation, and dechlorination. The in vitro metabolism of DMB and the metabolites it produces have not been studied before.

The World Health Organization identifies alcohol as a cause in several neoplasias of the oro-pharynx cavity, esophagus, gastrointestinal tract, larynx, liver, or female breast. This study re-views ethanol's nonoxidative and oxidative metabolism and one-carbon metabolism that en-compasses both redox and transfer reactions that influence crucial cell proliferation machinery. Ethanol favors the uncontrolled production and action of free radicals that interfere with the maintenance of essential cellular functions. We focus on the generation of protein, DNA, and lipid adducts that interfere with the cellular processes related to growth and differentiation. Ethanol's effects on stem cells responsible for building and repairing tissues are reviewed. Cancer stem cells suffer disturbances related to the expression of cell surface markers, enzymes, and transcription factors after ethanol exposure with consequent dysregulation of mechanisms related to cancer metastasis or resistance to treatments. Our analysis aims to underlie and discuss potential targets that show more sensitivity to ethanol's action and identify specific metabolic routes and metabolic realms that may be corrected to recover metabolic homeostasis after pharmacological interven-tion. Specifically, research should pay attention to reestablish metabolic fluxes by fine-tuning the functioning of specific pathways related to one-carbon metabolism and antioxidant processes.