N-Propargylic beta-enaminones have been used as common intermediates for the synthesis of polysubstituted pyrroles and pyridines. Best results have been obtained using DMSO as solvent. In the presence of Cs(2)CO(3) N-propargylic beta-enaminones are cyclized to pyrroles in good to high yields, whereas omitting bases and using CuBr leads to the selective formation of pyridines.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/ol800518j | DOI Listing |
J Org Chem
August 2024
Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India.
Herein we disclose a transition-metal-free, one-pot two-step strategy for the synthesis of unsymmetrical bis-heteroaryl ketones. -propargylic β-enaminones generated by the Michael addition of propargylamines onto heteroaryl 1,2-alkynediones have been utilized as synthetic equivalents of pyridine or pyrrole scaffolds. The use of alcohol as a solvent resulted in the formation of 2-alkoxylated pyridine scaffold, whereas the use of DMSO promoted the formation of a pyrrole motif.
View Article and Find Full Text PDFChem Biodivers
November 2023
Department of Chemistry, Middle East Technical University, 06800, Ankara, Turkey.
The study aimed to investigate the in vitro inhibitory activities of spiro N-propargylic β-enaminones, SPEs 1-31, against BCa cells, to perform in silico molecular docking studies to understand the nature of the interaction between the compounds and the ERα, PR, EGFR, and Her2, and to determine the ADMET and drug-likeness properties. Cytotoxic activity was investigated via MTT assay. DNA fragmentation was evaluated via ELISA assay.
View Article and Find Full Text PDFJ Biochem Mol Toxicol
April 2023
Department of Chemistry, Middle East Technical University, Ankara, Turkey.
Breast cancer is one of the most common cancers worldwide and the discovery of new cytotoxic agents is needed. Enaminones are regarded to be a significant structural motif that is found in a variety of pharmacologically active compounds however the number of studies investigating the anticancer activities of N-propargylic β-enaminones (NPEs) is limited. Herein we investigated the potential cytotoxic and apoptotic effects of 23 different NPEs (1-23) on human breast cancer cells.
View Article and Find Full Text PDFJ Org Chem
May 2021
Department of Chemistry, Middle East Technical University, 06800 Ankara, Turkey.
A one-pot two-step protocol for the synthesis of 2-acetyl-1-pyrroles from -propargylic β-enaminones was described. When treated with zinc chloride in refluxing chloroform, -propargylic β-enaminones produced in situ 2-methylene-2,3-dihydro-1,4-oxazepines, which, upon further refluxing in methanol with zinc chloride, afforded 2-acetyl-1-pyrroles. The process was found to be general for a wide variety of -propargylic β-enaminones and yielded a diverse range of 2-acetyl-1-pyrroles in good to high yields with large substrate scope and good functional group tolerance.
View Article and Find Full Text PDFJ Org Chem
April 2020
Department of Chemistry, Middle East Technical University, 06800 Ankara, Turkey.
A facile and efficient method for the synthesis of 3-[(4-nitrophenyl)thio]-substituted 4-methylene-1-pyrrolines is described. When treated with 4-nitrobenzenesulfenyl chloride in refluxing acetonitrile, -propargylic β-enaminones produced α-sulfenylated -propargylic β-enaminones, which, in the presence of sodium hydride or cesium carbonate, underwent nucleophilic cyclization to afford 4-methylene-3-[(4-nitrophenyl)thio]-1-pyrrolines in good to high yields. It was shown for the first time that on -propargylic β-enaminone systems, α-sulfenylation dominates over the formation of thiirenium ion.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!