Spectroscopic studies of ether rifamycins (1-9) have shown that all these compounds tend to be zwitterions with different localizations of intramolecularly transferred proton, which influences their solubility and logP values. According to ESI MS studies, rifamycins 3 and 4 form complexes with Li(+) or Na(+), while the other ones (7-9) coordinate small organic molecules, which can be further replaced by Na(+) cation. Biological assays revealed that the use of 7-9 in the form of complexes with small organic molecules improves their antibacterial potency as a result of changed: logP, solubility and binding mode with bacterial RNA polymerases.
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http://dx.doi.org/10.1016/j.bmcl.2015.07.043 | DOI Listing |
Anal Chem
January 2025
Department of Pharmaceutical Biosciences, Spatial Mass Spectrometry, Science for Life Laboratory, Uppsala University, SE-75124 Uppsala ,Sweden.
Multiomics analysis of single tissue sections using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) provides comprehensive molecular insights. However, optimizing tissue sample preparation for MALDI-MSI to achieve high sensitivity and reproducibility for various biomolecules, such as lipids, -glycans, and tryptic peptides, presents a significant challenge. This study introduces a robust and reproducible protocol for the comprehensive sequential analysis of the latter molecules using MALDI-MSI in fresh-frozen rodent brain tissue samples.
View Article and Find Full Text PDFRSC Adv
January 2025
Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University Changsha 410081 China
Herein, we discuss the idea that fluorescent materials/molecules should logically show potential photoelectrochemistry (PEC) activity, and, in particular, the PEC of fluorescent small molecules (previously usually acting only as dye sensitizers for conventional semiconductors) is explored. After examining the PEC activities of some typical inorganic or organic fluorescent materials/molecules and by adopting methyl violet (MV) with the highest PEC activity among the examined fluorescent small molecules, a new and efficient (MV/Au nanoparticles (AuNPs))/fluorine-doped tin oxide (FTO) photoanode without conventional semiconductor(s) is prepared by layer-by-layer alternating the electrodeposition of AuNPs and the adsorption of MV. A bilirubin oxidase (BOD)/CuCoO/FTO bio-photocathode is prepared by electrodeposition, calcination and cast-coating.
View Article and Find Full Text PDFTurk J Chem
October 2024
Supramolecular Compounds Division, Institute of General and Inorganic Chemistry, Uzbekistan Academy of Sciences, Tashkent, Uzbekistan.
The cocrystal (or supramolecular complex) between the Cu(II) complex of salicylic acid and uncoordinated piracetam has been synthesized. Its structure is characterized by elemental analysis, FT-IR, UV-Vis spectroscopy, and X-ray crystallography. Spectroscopic methods confirm the formation of the metal complex, while X-ray crystallography establishes the molecular and crystal structure of the obtained compound.
View Article and Find Full Text PDFTurk J Chem
November 2024
Division of Organic Chemistry, Department of Chemistry, Faculty of Engineering, İstanbul University-Cerrahpaşa, İstanbul, Turkiye.
The detection of intracellular biothiols (cysteine, N-acetyl cysteine, and glutathione) with high selectivity and sensitivity is important to reveal biological functions. In this study, a 2-(2-methoxy-4-methylphenoxy)-3-chloro-5,8-dihydroxynaphthalene-1,4-dione (DDN-O) compound was newly synthesized and used as a fluorogenic probe (detector molecule) in the fluorometric method for the rapid, highly selective, and sensitive determination of biothiols. The intensity values (λ = 260 nm, λ = 620 nm) of the product were measured by adding biothiols to the reaction medium at varying concentrations and the glutathione equivalent thiol content values of each biothiol were calculated.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of Science and Technology Beijing, School of Chemistry and Biological Engineering, CHINA.
Designing and realizing new topologies represent one of the most important ways toward developing new structures and functionalities for molecule-based frameworks including SOFs, MOFs, and COFs. Herein, Aldol condensation between 5,10,15,20-tetrayl(tetrakis(([1,1':3',1''-terphenyl]-4,4''-dicarbaldehyde)))-porphyrin (TTEP) and 2,4,6-trimethyl-1,3,5-triazine (TMT) affords the vinylene-linked 3D covalent organic framework Por-COF-cya. Powder X-ray diffraction (PXRD) in combination with structural simulation reveals its high crystalline structure with an unprecedented cya topology in the molecule-based frameworks reported thus far.
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