Pyrimidodiazepine derivatives underwent an unexpected gold-catalyzed retro-Mannich-type carbon-carbon bond cleavage and intramolecular nucleophilic cyclization. The pyrimidodiazepines bearing an alkyne moiety showed novel orthogonal reactivity in the presence of a gold catalyst, as opposed to the alkynophilicity that is commonly observed with gold catalysts. The ring transformation reaction of pyrimidodiazepines probably proceeds through an acyclic iminium intermediate. The potential of this synthetic method for the skeletal diversification of pyrimidine-containing macrocycles was also demonstrated.
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http://dx.doi.org/10.1021/acs.orglett.6b03520 | DOI Listing |
J Nat Prod
January 2025
Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.
Six new aurovertins (-) and a new citreoviridin derivative (), together with six known analogues (-), were isolated from the marine-derived sp. OUCMDZ-5930. Their structures were determined based on detailed spectroscopic analysis and ECD calculations.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Key Laboratory of Enzyme Engineering of Agricultural Microbiology (Ministry of Agriculture), School of Life Sciences, Henan Agricultural University, Zhengzhou, Henan Province, 450046, China.
The antibiotic tetracycline (TC) is an emerging pollutant frequently detected in various environments. Although enzymatic remediation is a promising strategy for mitigating TC contamination, the availability of effective TC-degrading enzymes remains limited, and their mechanisms and applications are not fully understood. This study developed a comprehensive TC-degrading enzyme library from the gut microbiome of the highly TC-resistant saprophagous insect, black soldier fly larvae (BSFL), using an integrated metagenomic and comparative metatranscriptomic approach, identifying 105 potential novel TC-degradation genes.
View Article and Find Full Text PDFRSC Adv
January 2025
Department of Chemistry, Universidad de Los Andes Carrera 1 No. 18A-10 Bogotá 111711 Colombia
An isomerization reaction of 7-aryl-3-formylpyrazolo[1,5-]pyrimidines to 5-aroyl-NH-pyrazolo[3,4-]pyridines proceeding with high yields in aqueous NaOH under microwave conditions is reported. This unprecedented transformation occurs by adding and eliminating a water molecule an ANRORC mechanism (adding the nucleophile, ring-opening, and ring-closing) studied using DFT calculations. The product's utility was proved as they have aroyl and NH groups that simple methods and readily available reagents easily modified; likewise, their optical properties were studied, highlighting their high potential as highly emissive modular dyes ( up to 99%).
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Yunnan University, Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, East Outer Ring Road, 650500, Kunming, CHINA.
The reduction of carboxylic esters to aldehydes and alcohols is a fundamental functional group transformation in chemistry. However, the inertness of carbonyl group and the instability of ketyl radical anion intermediate impede the reduction of carboxylic esters via photochemical strategy. Herein, we described the reduction of aliphatic carboxylic esters with synergistic dual photocatalysis via phenolate-catalyzed single electron transfer process and thiol-catalyzed hydrogen atom transfer process.
View Article and Find Full Text PDFCell Biochem Biophys
January 2025
Department of Electronics and Communication Engineering, Hajee Mohammad Danesh Science and Technology University, Dinajpur, 5200, Bangladesh.
Blood components play a crucial role in maintaining human health and accurately detecting them is essential for medical diagnostics. A cutting-edge sensor utilizing PCF revealed to precisely identify a wide range of blood components with WBCs (white blood cells), RBCs (red blood cells), HB (hemoglobin), platelets, and plasma. A numerical analysis was performed using COMSOL Multiphysics software to assess the capabilities of the sensor.
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