Under solvent-free conditions, thiosalicylic acid (2) efficiently self-promotes the thiolysis of 1,2-epoxides 1, anti-stereoselectively and generally totally beta-regioselectively. The resulting beta-hydroxysulfide products 3 have been obtained in very good yields. Benzo[e]1,4-oxathiepin-5-ones 4 have been easily prepared in a regio- and diasteroselective manner and in satisfactory yields under SFC by a one-pot protocol including nucleophilic ring opening of 1,2-epoxides 1 by thiosalicylic acid (2) and thermally induced lactonization of beta-hydroxy arylsulfides 3. Solvent-free condition and the absence of any catalyst make this procedure atom-economical and environmentally friendly.
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http://dx.doi.org/10.1021/jo0487496 | DOI Listing |
Ultrason Sonochem
January 2025
Department of Chemical Engineering, National Chung Hsing University, Taichung 402, Taiwan. Electronic address:
Chlorogenic acid, a well-known antioxidant, has potential applications in health care, food, and cosmetic sectors. However, its low solubility hinders its application at the industrial scale. The primary goal of the present study was to increase the lipophilic property of chlorogenic acid through esterification using an ultrasonication approach and Novozym® 435 as the catalyst.
View Article and Find Full Text PDFCurr Top Med Chem
January 2025
Department of Pharmaceutical Chemistry, JSS College of Pharmacy, JSS Academy of Higher Education & Research (JSS AHER), Mysuru, Karnataka, India.
Background: Several chemical studies described the physiological efficacy of 1,4- dihydropyridines (DHPs). DHPs bind to specific sites on the α1 subunit of L-type calcium channels, where they demonstrate a more pronounced inhibition of Ca2+ influx in vascular smooth muscle compared to myocardial tissue. This selective inhibition is the basis for their preferential vasodilatory action on peripheral and coronary arteries, a characteristic that underlies their therapeutic utility in managing hypertension and angina.
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
Department of Natural Products & Medicinal Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India.
A new one-pot approach was developed for the construction of pyrano[3,2-]chromene-2,5-diones by reacting 4-hydroxycoumarins with ethyl 3-oxo-3-phenylpropanoates in the presence of ammonium salts or aminocrotonates under solvent-free conditions. The title compounds were formed by intramolecular cyclization through new C-C and C-O bonds. Structure assignment of compound 3e was confirmed by single crystal X-ray analysis.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Laboratorio de Química Sintética Sostenible (QuimSinSos), Departamento de Química Orgánica e Inorgánica, (IUQOEM) and ORFEO-CINQA, Facultad de Química, Universidad de Oviedo, E33071 Oviedo, Spain.
The straightforward organocatalytic insertion of carbon disulfide (CS) into epoxides using either choline chloride () or tetrabutylammonium chloride (TBACl) is reported, for the first time, under solvent-free (neat) conditions. Fine-tuning of our system allowed us to obtain either dithiocarbonates (DTCs) or trithiocarbonates (TTCs) with high efficiency. Additionally, a mechanistic proposal is presented, supported by experimental evidence, DFT calculations and wavefunction analyses.
View Article and Find Full Text PDFJ Org Chem
January 2025
Department of Chemistry and Biochemistry, University of Nevada Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada 89154-4003, United States.
A hydropersulfide-mediated hydrothiolation reaction of alkenes has been developed for C-S bond formation with Markovnikov selectivity. This new approach is a transition-metal-, additive-, and solvent-free reaction under mild conditions. The reaction is postulated to proceed by an ionic mechanism with the release of elemental sulfur based on our control experiments and density functional theory calculations.
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