title: Efficacy of 4-methyl-7-hydroxy coumarin derivatives against vectors Aedes aegypti and Culex quinquefasciatus.
abstract: 4-Methyl-7-hydroxy coumarin is considered as a lead molecule as a biopesticide. Its mono bromo and tribromo derivatives were synthesized. Two more derivatives were synthesized by acylation. Compound 1 (3,6,8-tribromo-7-hydroxy-4-methyl-chromen-2-one) was found to be the most potent against IVth instar larvae of C. quinquefasciatus and A. aegypti the LC50 being 1.49 and 2.23 ppm respectively. It showed 100% larval mortality at 25 ppm against A. aegypti and at 10 ppm against C. quinquefasciatus. Compounds 1 and 2 (3,6,8-tribromo-7-hydroxy-4-methyl-chromen-2'-oxo-2H-chromen-7-yl acetate) showed remarkable ovicidal activity. Significant reduction of 80-85% hatching of eggs of both mosquito species was observed at the highest dose of 100 ppm. The hatched larvae showed 100% mortality in the successive instars. Compounds 3 and 4 (3-bromo-7-hydroxy-4-methyl-chromen-2-one and 3-bromo-4-methyl-2'-oxo-2H-chromen-7-yl acetate) showed moderate activity against both mosquito species.
authors.affiliation: Department of Chemistry, Sir Parshurambhau College, Pune 411 030, India. madhaviarya@rediffmail.com
authors.forename: Madhavi
authors.initials: M
authors.lastname: Deshmukh
authors.forename: Pushpa
authors.initials: P
authors.lastname: Pawar
authors.forename: Mary
authors.initials: M
authors.lastname: Joseph
authors.forename: Usha
authors.initials: U
authors.lastname: Phalgune
authors.forename: Rajashree
authors.initials: R
authors.lastname: Kashalkar
authors.forename: Nirmala R
authors.initials: NR
authors.lastname: Deshpande
mesh_terms: D000330:Aedes / Q000187:drug effects; D000818:Animals; D001681:Biological Assay; D002626:Chemistry, Pharmaceutical / Q000379:methods; D003465:Culex / Q000187:drug effects; D015195:Drug Design; D004353:Drug Evaluation, Preclinical; D006923:Hymecromone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry; D007305:Insecticide Resistance / Q000187:drug effects; D007306:Insecticides / Q000494:pharmacology; D007814:Larva / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D009032:Mosquito Control; D010575:Pesticides / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D007306:Insecticides; D010575:Pesticides; D006923:Hymecromone