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Showing papers by "Tom J. Mabry published in 1987"


Journal ArticleDOI
TL;DR: In this paper, the previously reported isoscutellarein 7-O-[6″'-O-acetyl-β- D -allopyranosyl-(1 → 2)-β-D -glucopyranside] (1) and 3′-hydroxy-4′-O-methylisoscutelle-6″-methyl-isos cutelle-7-O[6″]-6″ -acetyl β-D-glucophyranoid glycoside [1] (2) were used to

63 citations


Journal ArticleDOI
TL;DR: Larvae feeding on sunflower inflorescences in laboratory and greenhouse bioassays performed significantly poorer on 14 Helianthus species than on the cultivar hybrid ‘894’, and the sesquiterpene lactone 8 β-sarracinoyloxycumambranolide isolated from glandular trichomes on anthers ofHelianthus maximiliani Schrader was toxic to young larvae in bioassay.
Abstract: Sunflower moth, Homoeosoma electellum (Hulst), is a major pest of cultivated sunflower, Helianthus annuus L., in North America. Thirty perennial and 11 annual species of Helianthus and several cultivars of sunflower were evaluated for resistance to H. electellum larvae. Larvae feeding on sunflower inflorescences in laboratory and greenhouse bioassays performed significantly poorer on 14 Helianthus species than on the cultivar hybrid ‘894’. In in vitro bioassays, nonpolar extracts from H. annuus, Helianthus argophyllus Torrey & Gray, Helianthus ciliaris DC, and Helianthus petiolaris ssp. petiolaris Nuttall caused significant lengthening of larval stadia and retarded larval growth. Larvae feeding on purified sesquiterpene lactones and diterpenes from H. argophyllus , H. ciliaris, Helianthus angustifolius L., and Helianthus mollis Lambert in a wheat-germ diet at 0.1–1.0% concentration experienced high mortality, retarded growth, and an extended developmental period. The sesquiterpene lactone 8 β-sarracinoyloxycumambranolide isolated from glandular trichomes on anthers of Helianthus maximiliani Schrader was toxic to young larvae in bioassays. Two mechanisms giving Helianthus resistance to seed injury by larvae of H. electellum are terpenes in the florets and phytomelanin in the pericarp of seeds.

52 citations


Journal ArticleDOI
TL;DR: Twelve sesquiterpenoid esters, including two new daucane and four new germacrane ester, were isolated from the roots of Ferula orientalis var.
Abstract: Twelve sesquiterpenoid esters, including two new daucane and four new germacrane esters, were isolated from the roots of Ferula orientalis var. orientalis. Structures for all compounds were elucidated by spectral methods and chemical transformations.

29 citations


Journal ArticleDOI
TL;DR: From the leaves and the flowers of Helianthus glaucophyllus andHelianthus microcephalus, three new guaianolides were isolated andStructures of all the compounds were determined by spectral analysis.
Abstract: From the leaves and the flowers of Helianthus glaucophyllus and Helianthus microcephalus, three new guaianolides were isolated. H. microcephalus afforded another two new guaianolides, the highly unsaturated guaianolide, the flavane, the flavone, and three flavonols. Structures of all the compounds were determined by spectral analysis.

23 citations




Journal ArticleDOI
TL;DR: In this article, ten apiene-type humulenoid esters were isolated from the root of Ferula haussknechtii and elucidated by spectroscopic methods.

14 citations


Journal ArticleDOI
TL;DR: In this article, a new sesquiterpene lactone, ladibranolide, was isolated from Viguiera ladibractate and its stereochemistry was established by NOE experiments.

14 citations


Journal ArticleDOI
TL;DR: In this paper, 13 flavonoids were isolated from the aerial parts of Iphiona scabra: 3-sulphate, 3,4′-disulphates and 3,7, 4′-trisulphating of isorhamnetin; the 3-7-disulo-phate and 3.7-4′ trisulphyte of quercetin; and the 7-Sulphatophate of hispidulin; 3-glucosides and 3-galactosides of

11 citations


Journal ArticleDOI
TL;DR: In this article, eleven flavonoids, including two new compounds, were isolated from Gutierrezia texana : the structures of the new compounds are 5,7,2′,5′-tetrahydroxy-3,4′-dimethoxyflavone and 5′-acetoxy-5, 7, 2′-trihydroxyltrihexyltrihydroxy -3, 4, 4′ -dimethylhexylhexoxy-3.

10 citations



Journal ArticleDOI
TL;DR: In this article, six known flavonoid aglycones and the newly described 5,7,4′-trihydroxy-3,3′,5′-trimethoxyflavone were isolated from Xanthocephalum gymnospermnoides var.

Journal ArticleDOI
TL;DR: In this article, eleven sesquiterpene lactones, six of which are new, were identified from Piptothrix pubens and all but one of the compounds contained a C 10 -diester attached at C-8.

Journal ArticleDOI
TL;DR: In this paper, three known thymol esters and five known sesquiterpene lactones, two new germacrolides and a new diterpenes diester were isolated from the dichloromethane extract of the aerial parts of Piptothrix sinaloae.

Journal ArticleDOI
TL;DR: Five sesquiterpene lactones with C 10 -diester side-chains have been identified as major constituents of a leaf surface extract of Carphochaete bigelovii by spectroscopic methods and are reported for the first time.


Journal ArticleDOI
TL;DR: Aster subulatus, flavone and flavonol aglycones, monoglycosides and a diglycoside of kaempferol as well as chlorogenic acid are reported from Astersubulatus.