title: Synthesis and insect antifeedant activity of plumbagin derivatives with the amino acid moiety.
abstract: A series of plumbagin derivatives (4a-4k) containing an amino acid moiety were synthesized under mild esterification conditions in excellent yields (35%-80%) and screened for their antifeedant activities in tobacco caterpillar (Spodoptera litura) and castor semilooper (Achaea janata) using a no-choice laboratory bioassay. The parent compound plumbagin lacked significant activity, but the analogues were effective in reducing feeding by two insect species. The introduction of an N-acetyl-l-amino acid side chain to the Michael adduct of plumbagin at the third position of the quinone moiety significantly increased antifeedant activity. Several of the analogues were also toxic or caused developmental abnormalities following topical administration.
authors.affiliation: Division of Organic Chemistry- I, Natural Product Laboratory, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500 607, India.
authors.forename: Thonthula
authors.initials: T
authors.lastname: Sreelatha
authors.forename: Atmakur
authors.initials: A
authors.lastname: Hymavathi
authors.forename: Katragadda Suresh
authors.initials: KS
authors.lastname: Babu
authors.forename: Joish Madhusudana
authors.initials: JM
authors.lastname: Murthy
authors.forename: Usha Rani
authors.initials: UR
authors.lastname: Pathipati
authors.forename: Janaswamy Madhusudana
authors.initials: JM
authors.lastname: Rao
mesh_terms: D000818:Animals; D016227:Benzoquinones / Q000737:chemistry; D004435:Eating / Q000187:drug effects; D007306:Insecticides / Q000008:administration & dosage / Q000138:chemical synthesis* / Q000737:chemistry; D007814:Larva / Q000502:physiology; D009036:Moths / Q000502:physiology*; D009285:Naphthoquinones / Q000008:administration & dosage / Q000737:chemistry*; D018411:Spodoptera / Q000502:physiology*; D013329:Structure-Activity Relationship; D013481:Superoxides
chemical_list: D016227:Benzoquinones; D007306:Insecticides; D009285:Naphthoquinones; D013481:Superoxides; C004532:quinone; C014758:plumbagin