An efficient cyclocondensation reactions, antimicrobial activity and molecular orbital calculations of α-benzopyrone derivatives
Open Access
- 30 June 2012
- journal article
- Published by European Journal of Chemistry in European Journal of Chemistry
- Vol. 3 (2), 172-178
- https://doi.org/10.5155/eurjchem.3.2.172-178.582
Abstract
An efficient synthesis of 4,6,8-trimethyl-2-oxo-2H-chromene-3-carbonitrile (2) via Claisen condensation of 3,5-dimethyl-2-hydroxyacetophenone with ethyl cyanoacetate in the presence of sodium metal is reported. Cyclocondensation reactions of compound (2) with ethyl acetate or with ethyl cyanoacetate in the presence of ethoxide gave sodium salt of 7-amino-9-hydroxy-2,4-dimethyl-6H-benzo[c]chromen-6-one derivatives (3) and (4) respectively, which upon neutralization with 10 % hydrochloric acid gave 7-amino-9-hydroxy-2,4-dimethyl-6H-benzo[c]chromen-6-one (5). Hydrolysis of compound (2) with ethanolic sodium hydroxide solution gave 4,6,8-trimethyl-2-oxo-2H-chromene-3-carboxylic acid (6). Treatment of compound (2) with Vilsmier reagent using excess POCl3 gave 4-(chloro(formyl)methyl-6,8-dimethyl-2-oxo-2H-chromene-3-carbonitrile (7). Also, conden-sation of compound (2) with DMF-DMA in xylene or with POCl3/DMF in pyridine gave the same product 4-((E)-2-(dimethylamino)vinyl)-6,8-dimethyl-2-oxo-2H-chromene-3-carbo-nitrile (8). The cyclocondensation reactions of compound (8) with hydroxylamine hydrochloride, urea, and with hydrazinecarbodithioic acid gave 3,4-dihydro-3-hydroxy-4-imino-7,9-dimethylchromeno[3,4-c]pyridin-5-one (9), 4-imino-7,9-dimethyl-5-oxo-4H-chro-meno[3,4-c]pyridine-3(5H)-carboxamide (10) and 3-amino-3,4-dihydro-4-imino-7,9-dimethyl chromeno[3,4-c]pyridin-5-one (11), respectively. Also, acid hydrolysis of compound (8) gave 7,9-dimethyl-3H-chromeno[3,4-c]pyridine-4,5-dione (12). Structures of the products were established on the basis of elemental analysis, IR, 1H and 13C NMR, mass spectra and semi-empirical AM1-MO calculations. The antimicrobial activities of the synthesized products were also studied.Keywords
This publication has 16 references indexed in Scilit:
- Cyclocondensation, antimicrobial activity and semi-empirical AM1-MO calculations of benzopyrone derivativesEuropean Journal of Chemistry, 2012
- Synthesis, antifungal activity and semi-empirical AM1-MO calculations of some new 4-oxo-4H-chromene derivativesEuropean Journal of Chemistry, 2011
- Synthesis of Bioactive 4-Oxo-4H-Chromenes Bearing Heterocyclic Systems from Hydrazonecarbodithioic Acid and ThiocarbohydrazonePhosphorus, Sulfur, and Silicon and the Related Elements, 2008
- New biscoumarin derivatives-cytotoxicity and enzyme inhibitory activitiesBioorganic & Medicinal Chemistry, 2006
- Synthesis, structure, toxicological and pharmacological investigations of 4-hydroxycoumarin derivativesEuropean Journal of Medicinal Chemistry, 2006
- Synthesis and Anticoagulant Activities of Substituted 2,4‐Diketochromans, Biscoumarins, and ChromanocoumarinsArchiv der Pharmazie, 2006
- Long‐Chain 3‐Acyl‐4‐hydroxycoumarins: Structure and Antibacterial ActivityArchiv der Pharmazie, 2006
- Design, synthesis and characterization of a novel class of coumarin-based inhibitors of inducible nitric oxide synthaseBioorganic & Medicinal Chemistry, 2005
- SYNTHETIC AND BIOLOGICAL STUDIES ON COUMARIN HYDRAZONE DERIVATIVESPhosphorus, Sulfur, and Silicon and the Related Elements, 2001
- Synthesis, antimicrobial activity and bleaching effect of some reaction products of 4-oxo-4H-benzopyran-3-carboxaldehydes with aminobenzothiazoles and hydrazidesIl Farmaco, 1998