title: Synthesis of novel biologically active heterocyclic compounds from 2-oxo-2H-benzopyran-6-yl-imidazolidine.
abstract: 6-Aminocoumarin on treatment with oxalyl chloride gives coumarinyl-6-isocynate (1a-c) which on treatment with glycine gives 1H-3-[2'-oxo-2'H-benzopyran-6'-yl]-5-imidazolidine-2, 4-dione (2a-c). (2a-c) when refluxed with o-chlorobenzaldehyde, m-hydroxybenzaldehyde, 3,4-dimethoxybenzaldehyde and 3-nitrobenzaldehyde separately gives 1H-5-(2"-chlorobenzylidene)-3-(2'-oxo-2'H-benzopyran-6'-yl) imidazolidine-2,4-dione (3a-c), 1H-5-(3"-hydroxybenzylidene)-3-(2'-oxo-2'H-benzopyran-6'-yl) imidazolidine-2,4-dione (4a-c), 1H-5-(3",4"-dimethoxybenzylidene)-3-(2'-oxo-2'H-benzopyran-6'-yl) imidazolidine-2,4-dione (5a-c) and 1H-5-(3"-nitrobenzylidene)-3-(2'-oxo-2'H-benzopyran-6'-yl) imidazolidine-2,4-dione (6a-c), respectively. 3-(2"-Chlorophenyl)-3a,4-dihydro-6-(2'-oxo-2'H-benzopyran-6'-yl) imidazo[4,5-c]isoxazol-5-one 7a-c is obtained from (3a-c) and hydroxylamine hydrochloride while 2,3a,4-trihydro-3-(3"-hydroxyphenyl)-6-(2'-oxo-2'H-benzopyran-6'-yl) imidazo[4,5-c]pyrazol-5-one (8a-c) obtained by reaction of (4a-c) with hydrazine hydrate. Compound (5a-c) on treatment with urea gives 5,7-dihydro-2-hydroxy-6-(3",4"-dimethoxyphenyl)-9-(2'-oxo-2'H-benzopyran-6'-yl) purin-8-one (9a-c) and compound (6a-c) on treatment with thiourea gives 5,7-dihydro-2-mercapto-6-(3"-nitrophenyl)-9-(2'-oxo-2'H-benzopyran-6'-yl)purin-8-one (10a-c). The structures of the compounds have been established on the basis of spectral analytical data. All the compounds have been screened for their antimicrobial activities against three bacterial strains S. aureus, S. typhi and E. coli. Compounds 2b, 3b, 4b, 5b, 6b, 7b, 8b, 9b and 10b with the presence of methyl groups at C7' and C8' of coumarin moiety were found to be more active than others.
authors.affiliation: Department of Chemistry, The Institute of Science, 15 Madam Cama Road, Mumbai 400 032, India. vinata_mulwad@hotmail.com
authors.forename: Vinata V
authors.initials: VV
authors.lastname: Mulwad
authors.forename: Bhushan P
authors.initials: BP
authors.lastname: Langi
authors.forename: Atul C
authors.initials: AC
authors.lastname: Chaskar
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000494:pharmacology; D001578:Benzopyrans / Q000138:chemical synthesis* / Q000494:pharmacology; D003374:Coumarins / Q000138:chemical synthesis* / Q000494:pharmacology; D052978:Disk Diffusion Antimicrobial Tests; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development; D008401:Gas Chromatography-Mass Spectrometry; D048289:Imidazolidines / Q000138:chemical synthesis* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D012485:Salmonella typhi / Q000187:drug effects / Q000254:growth & development; D017550:Spectroscopy, Fourier Transform Infrared; D013211:Staphylococcus aureus / Q000187:drug effects / Q000254:growth & development; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D001578:Benzopyrans; D003374:Coumarins; D048289:Imidazolidines; C067496:6-amino-1,2-benzopyrone