title: Isokotanins A-C: new bicoumarins from the sclerotia of Aspergillus alliaceus.
abstract: Three new bicoumarin metabolites, isokotanins A [1], B [2], and C [3], were isolated from the sclerotia of Aspergillus alliaceus. Isokotanin A is a regioisomer of the known bicoumarin kotanin [4]. The structures and spectral assignments for 1-3 were determined on the basis of selective INEPT, HMQC, and NOESY nmr data, as well as by chemical interconversions. Isokotanins B and C show activity against the corn earworm Helicoverpa zea and the dried fruit bettle Carpophilus hemipterus. The known compounds kotanin [4], desmethylkotanin [5], nominine, and paspaline were also isolated from extracts of A. alliaceus sclerotia.
authors.affiliation: Department of Chemistry, University of Iowa, Iowa City, 52242.
authors.forename: J A
authors.initials: JA
authors.lastname: Laakso
authors.forename: E D
authors.initials: ED
authors.lastname: Narske
authors.forename: J B
authors.initials: JB
authors.lastname: Gloer
authors.forename: D T
authors.initials: DT
authors.lastname: Wicklow
authors.forename: P F
authors.initials: PF
authors.lastname: Dowd
mesh_terms: D000818:Animals; D001230:Aspergillus / Q000737:chemistry*; D003374:Coumarins / Q000302:isolation & purification* / Q000633:toxicity; D007313:Insecta; D007306:Insecticides / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy
chemical_list: D003374:Coumarins; D007306:Insecticides; C086778:isokatanin A; C086781:isokatanin B; C086782:isokatanin C