The eleven-step preparation of the bicyclic 2-pyridone dipeptide mimetic 1 [(3S)-6-(benzyloxycarbonylamino)-5-oxo-1,2,3,5-tetrahydroindolizine-3-carboxylic acid] in optically active form (60% ee) is described. Key steps in the synthesis of 1 include the osmium-catalyzed asymmetric dihydroxylation of olefin 13 [(6-but-3-enyl-2-methoxypyridin-3-yl)carbamic acid benzyl ester] and the intramolecular cyclization of protected diol 19 [(3'R)-[6-[4'-(tert-butyldimethylsilanyloxy)-3'-hydroxybutyl]-2-methoxypyridin-3-yl]carbamic acid benzyl ester] to afford the pyridinium salt 20 [(3S)-[3-(tert-butyldimethylsilanyloxymethyl)-5-methoxy-2,3-dihydro-1H-indolizin-6-yl]carbamic acid benzyl ester trifuoromethanesulfonic acid salt]. Several alternate methods to prepare olefin 13 are also discussed.
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http://dx.doi.org/10.1021/jo010712n | DOI Listing |
Org Biomol Chem
January 2025
Institute of Condensed Matter and Nanosciences, Molecules Solids and Reactivity (IMCN/MOST), Université Catholique de Louvain, Bâtiment Lavoisier, Pl. Louis Pasteur, 1, bte 3. 1348, Louvain La Neuve, Belgium.
The present study describes the use of the di--butyl dicarbonate (BocO)/4-(,-dimethylamino)pyridine (DMAP) system for the amidation of carboxylic acids under neat conditions without heating. A set of carboxylic acids was explored, such as non-steroidal anti-inflammatory drugs (NSAIDs), fatty acids and protected prolines in the presence of aromatic, benzylic and aliphatic amines as nucleophilic partners. The scope of this easy approach was extended to the preparation of thirty-two diverse carboxylic amides, which were recovered with isolated yields varying from moderate to excellent.
View Article and Find Full Text PDFPharmaceutics
January 2025
Laboratory of Nuclear Medicine (LIM-43), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-911, SP, Brazil.
Background/objectives: Dithiocarbazates (DTCs) and their metal complexes have been studied regarding their property as anticancer activities. In this work, using S-benzyl-5-hydroxy-3-methyl-5-phenyl-4,5-dihydro-1H-pirazol-1-carbodithionate (Hbdtc), we prepared [ReO(bdtc)(Hbdtc)] and [[Tc]TcO(bdtc)(Hbdtc)] complexes for tumor uptake and animal biodistribution studies.
Methods: Re complex was prepared by a reaction of H2bdtc and (NBu)[ReOCl], the final product was characterized by IR, H NMR, CHN, and MS-ESI.
Molecules
January 2025
Department of Organic Chemistry and Technology, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Műegyetem rkp. 3, 1111 Budapest, Hungary.
Butyl phenyl--phosphinate that is not available commercially was prepared from phenyl--phosphinic acid by three methods: by alkylating esterification (i), by microwave-assisted direct esterification (ii), and unexpectedly, by thermal esterification (iii). Considering the green aspects, selectivity and scalability, the thermal variation seemed to be optimal. However, there was need for prolonged heating.
View Article and Find Full Text PDFNat Prod Res
January 2025
Department of Nanotechnology and Advanced Materials, Mersin University, Mersin, Turkey.
Propolis, a natural product with remarkable therapeutic potential, has gained attention for its antimicrobial, antioxidant, and anti-inflammatory properties. In this study, propolis samples from Sarıyaprak, Kovanağzı, and Çemikari in Pervari, Siirt province, were analysed comprehensively. The evaluation included wax composition, DPPH and FRAP assays, total phenolic and flavonoid content, and pollen analysis.
View Article and Find Full Text PDFMol Divers
January 2025
School of Nuclear Technology and Chemistry & Biology, Hubei University of Science and Technology, Xianning, 437100, China.
A series of new arecoline derivatives containing amino acid fragments were synthesized, and their fungicidal activities were investigated. All synthesized compounds were characterized by H NMR, CNMR, and HRMS. Preliminary bioactivity assays demonstrated that Compounds 3k, 3n, 3p, 3q, 3r, and 3s exhibited significant antifungal activity against Botryosphaeria cactivora, Botryosphaeria dothidea, and Fusarium pseudograminearum at a concentration of 100 μg/mL.
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