Cyclocondensation, antimicrobial activity and semi-empirical AM1-MO calculations of benzopyrone derivatives

Abstract

An efficient synthesis of 7-amino-9-hydroxy-6-oxo-6H-benzo[c]chromene-8-carbonitrile derivatives (2,6) and 4-methyl-2-oxo-2H-chromene-3-carbonitrile (5) via Claisen condensation of 2-hydroxyacetophenones (1,3) with ethyl cyanoacetate in the presence of sodium metal is reported. Reaction of 5 with thiosemicarbazide gave 1-(3-cyano-4-methyl-2oxoquinolin-1(2H)-yl)thiourea (7). Treatment of 5 with 6,8-dichloro-4-oxo-4H-chromene-3carboxaldehyde gave 4-(2-(6,8-dichloro-4-oxo-4H-chromen-3-yl)-2-hydroxyethyl)-2-oxo-2Hchromene-3-carbonitrile (9). Further treatment of 5 with ethyl acetate followed by condensation with 6,8-dichloro-3-formylchromone gave 7-((6,8-dichloro-4-oxo-4H-chromen-3-yl)methyleneamino)-9-hydroxy-6H-benzo[c]chromen-6-one (12). Structures of the products were established on the basis of elemental analysis, IR, 1 H and 13 C NMR, mass spectra and semi-empirical AM1-MO calculations. The antimicrobial activities of the synthesized products were also studied. Synthesis Benzopyrone 4-Quinolinone Cyclocondensation AM1-MO calculation Antimicrobial activity

3-Formylchromones as diverse building blocks in heterocycles synthesis

“…Reaction of 6,8-dichloro-3-formylchromone (1q) with 4-methyl-2-oxo-2H-chromone-3-carbonitrile (19) gave the addition product 20 as recently reported by El-Shaaer [28]. While Melikyan et al [29] isolate the condensation products 21 on the reaction of 1a-d with compound 19 in refluxing toluene (Scheme 9).…”

An efficient synthesis of some new isolated and fused 2-oxo-2H-chromene derivatives as antimicrobial and antitumor agents

“…In our recent work, we described the condensation of 3,5-dichloro-2-hydroxyacetophenone [2], 3,5-dimethyl-2-hydroxy acetophenone [18] and unsubstituted 2-hydroxyacetophenone [2] with ethyl cyanoacetate in the presence of sodium metal gave 7-amino-2,4-dichloro(or 2,4-dimethyl)-9-hydroxy-6-oxo-6H-benzo[c]chromene-8-carbonitrile, and a mixture of 4-methyl-2-oxo-2H-chromene-3-carbonitrile and 7-amino-9-hydroxy-6-oxo-6H-benzo[c]chromene-8-carbonitrile, respectively.…”

“…Mass spectra recorded on a Gas chromatographic GCMSqp 1000 ex Shimadzu instrument at 70 eV. 4-Methyl-2-oxo-2H-chromene-3-carbonitrile (1) [2], 4-amino-6-methyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one [19] were prepared by previously reported procedures. All other chemicals used in this study were commercially available.…”

“…With the expectations to find biological activity, we decided to investigate the synthesis of some novel systems of 2-oxo-2H-chromene derivatives bearing fused and isolated moieties. Recently, the synthesis [14], photochemical [15], and theoretical [2,[16][17][18] properties of chromene derivatives were investigated.…”

“…Fused and isolated 2-oxo-2H-chromenes (coumarins) comprise a very interesting class of compounds due to their significant antibacterial [1], antifungal [2][3][4], antimycobecterial [5,6], anticoagulants [7,8], inhibition of some enzymes [9,10] and antitumor [11][12][13] activities. With the expectations to find biological activity, we decided to investigate the synthesis of some novel systems of 2-oxo-2H-chromene derivatives bearing fused and isolated moieties.…”