Disclosed in this Letter is a novel asymmetric addition of alkynyl nucleophiles to -alkylpyridinium electrophiles. The coupling is effected under mild and simple reaction conditions, affording dihydropyridine products with complete regiochemical and stereochemical control. In addition to several manipulations of the dihydropyridine products, the utility of this transformation is demonstrated through a concise, dearomative, and asymmetric synthesis of (+)-lupinine, a natural acetylcholine esterase inhibitor.
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http://dx.doi.org/10.1021/acs.orglett.1c02276 | DOI Listing |
Chemistry
January 2025
University of Nottingham, The GSK Carbon Neutral Laboratories for Sustainable Chemistry, Jubilee Campus, Triumph Road, NG7 2TU, Nottingham, UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND.
The nucleophilic propargylation of azinium ions with a propargylboronate proceeds efficiently under gold(I) catalysis. A range of N-alkylated pyridinium, quinolinium, and pyrazinium ions undergo propargylation with good yields and high regioselectivities to give various functionalized 1,4-dihydropyridines, 1,2-dihydropyridines, 1,4-dihydroquinolines, 1,2-dihydroquinolines, and 4,5-dihydropyrazines. No allenylation side-products are observed.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Organisch-Chemisches Institut, Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
Herein we report a simple BF-catalyzed cycloaddition of dihydropyridines with bicyclobutanes for the expedient synthesis of novel three-dimensional azacycle-fused bicyclo[2.1.1]hexane scaffolds.
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 PDFRSC Adv
December 2024
Bioorganic Laboratory, Department of Chemistry, University of Delhi Delhi-110007 India
A synthesis of a small library of fluorescent 1,4-dihydropyridine nucleoside analogues has been successfully carried out under solvent-free conditions a one-pot three-component Hantzsch condensation reaction. The process involved a Ba(NO) catalyzed solvent-free reaction between 3',5'-di--acetyl-5-formyl-2'-deoxyuridine, differently substituted β-keto ester and ammonium acetate under microwave irradiation. This facile methodology yielded the desired products with very high yields (86-96%) under solvent-free reaction conditions in a short reaction time, which was followed by a simple workup.
View Article and Find Full Text PDFJ Chromatogr A
January 2025
Pharmaceutical Chemistry Department, Faculty of Pharmacy, Cairo University, Kasr El-Aini St., Cairo 11562, Egypt. Electronic address:
Numerous studies have demonstrated the benefits of amlodipine and perindopril combination therapy in decreasing blood pressure and improving outcomes for high-risk patients. In order to assess the pharmacokinetics of the 2 drugs along with perindoprilat; the active metabolite of perindopril, a simultaneous LC-MS/MS quantification method of amlodipine (AML), perindopril (PER) and perindoprilat (LAT) in human plasma has been developed and validated using amlodipine D4, perindopril D4 and perindoprilat D4 as internal standards (ISs), respectively. A simple and fast protein precipitation method was used to analyze the three analytes from KEDTA human plasma.
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