[52]Dodecaphyrin(1.1.0.1.1.0.1.1.0.1.1.0) was quantitatively oxidized with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) to the corresponding [50]dodecaphyrin. Further oxidation of [50]dodecaphyrin with MnO2 quantitatively afforded [48]dodecaphyrin. Of the three, [50]dodecaphyrin showed Hückel aromatic character as the largest aromatic molecule reported to date. Protonation of [50]dodecaphyrin with methanesulfonic acid (MSA) led to the formation of a planar tetraprotonated species that displayed a sharp and intense Soret-like band at 906 nm with ε=6.5×10(5) M(-1) cm(-1) and Q-band-like bands at 1346 and 1600 nm.
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http://dx.doi.org/10.1002/chem.201500650 | DOI Listing |
J Chromatogr B Analyt Technol Biomed Life Sci
January 2025
Universite Claude-Bernard Lyon 1, CNRS, CPE-Lyon, CP2M, UMR 5128, Villeurbanne, France. Electronic address:
Carboxylic acids and aromatic compounds are essential building blocks and starting materials for the production of a wide range of fine chemicals and materials. Their recovery from kraft black liquor, an industrial effluent from pulp and paper mills, is a promising way to produce alternative bio-based chemicals. Reliable methods are needed to identify and quantify the molecules of interest in complex mixtures such as black liquors.
View Article and Find Full Text PDFProtoplasma
January 2025
Botany Unit (SAIF & R), CSIR-CDRI, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, Uttar Pradesh, India.
Eclipta prostrata belongs to the Asteraceae family. The plant contains bioactive compounds like wedelolactone (WDL) and demethylwedelolactone (DW). Its transcriptomic information engaged with secondary metabolite biosynthesis is not available.
View Article and Find Full Text PDFAnal Chem
January 2025
Xinjiang Key Laboratory of Trace Chemical Substances Sensing, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830000, China.
The specific fluorescent detection of α-methyltryptamine (AMT) presents a great challenge because similar amine groups and benzene rings exist in a variety of amines. Here, we show the precise modulation of the electron-withdrawing strength of the π-conjugate bridge in aldehyde-containing Schiff base-based fluorescent probes for ultratrace AMT discrimination. It is found that different electron-withdrawing groups -CH, -CHN, and -CHBr as the π-conjugate bridge of the 2-dicyanomethylidene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF)-based probes can classify and identify organic amines with different amine nucleophilicities.
View Article and Find Full Text PDFAppl Environ Microbiol
January 2025
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
Lignin contains a variety of interunit linkages, leading to a range of potential decomposition products that can be used as carbon and energy sources by microbes. β-O-4 linkages are the most common in native lignin, and associated catabolic pathways have been well characterized. However, the fate of the mono-aromatic intermediates that result from β-O-4 dimer cleavage has not been fully elucidated.
View Article and Find Full Text PDFBioTech (Basel)
December 2024
The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Nishihara 903-0213, Okinawa, Japan.
Functionally important amino acid sequences in proteins are often located at multiple sites. Three-dimensional structural analysis and site-directed mutagenesis may be performed to allocate functional sites for understanding structure‒function relationships and for developing novel inhibitory drugs. However, such methods are too demanding to comprehensively cover potential functional sites throughout a protein chain.
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