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1.
Experientia ; 47(3): 304-6, 1991 Mar 15.
Article in English | MEDLINE | ID: mdl-2009944

ABSTRACT

Dithyreanitrile, a novel sulfur-containing indole alkaloid, was isolated from the seeds of Dithyrea wislizenii (Cruciferae). Dithyreanitrile inhibits feeding of fall armyworm (Spodoptera frugiperda) and European corn borer (Ostrinia nubilalis) larvae. Dithyreanitrile, the first natural product with two sulfur atoms and a nitrile attached to the same carbon, was characterized by X-ray diffraction, spectroscopy, and chemical synthesis.


Subject(s)
Alkaloids/toxicity , Feeding Behavior/drug effects , Insecta/drug effects , Alkaloids/isolation & purification , Animals , Magnetic Resonance Spectroscopy , Seeds , X-Ray Diffraction
2.
J Nat Prod ; 54(1): 241-6, 1991.
Article in English | MEDLINE | ID: mdl-2045819

ABSTRACT

An extract of the seed of Sandoricum koetjape has yielded two new limonoids, sandoricin [1] and 6-hydroxysandoricin [2]. Both compounds are effective antifeedants when incorporated into artificial diets and fed to fall armyworm (Spodoptera frugiperda) or European corn borer (Ostrina nubilalis) larvae. Reduced growth rates and increased times to pupation were evident at lower dose levels while significant mortality was noted at higher dose levels. Structures of both compounds were determined by 1H nmr, 13C nmr, and ms and confirmed by X-ray crystallography.


Subject(s)
Insecticides , Limonins , Moths , Plants/analysis , Triterpenes/pharmacology , Animals , Chi-Square Distribution , Feeding Behavior/drug effects , Insecticides/chemistry , Insecticides/isolation & purification , Larva , Molecular Structure , Moths/physiology , Seeds/analysis , Triterpenes/chemistry , Triterpenes/isolation & purification
3.
J Chem Ecol ; 15(1): 121-8, 1989 Jan.
Article in English | MEDLINE | ID: mdl-24271431

ABSTRACT

Hexane and ethanol extracts of seeds from 10 plant species (including neem-Azadirachta indica A. Juss.) of the family Meliaceae were incorporated into artificial diet at various doses and fed to fall armyworm [Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)] larvae in nochoice tests. All produced significant mortality, reduced larval growth rate, increased time to pupation, or all three, at some concentration. The two highest doses of all of the ethanol extracts caused 100% mortality before pupation, but the hexane extracts tended to be less effective.Aglaia cordata Hiern. ethanol extract was as potent as the comparable neem seed extract at virtually all levels, and its hexane extract was active at much lower concentrations than the neem extract was. The sublethal effects (slower growth and increased time to pupation) were usually detectable at lower doses of extract than mortality was.

5.
J Chem Ecol ; 14(1): 237-52, 1988 Jan.
Article in English | MEDLINE | ID: mdl-24277007

ABSTRACT

Reactions of lesser peachtree borer [Synanthedon pictipes (G&R)] to volatiles of peach wood, either natural or chemically fractionated, were observed. Mated females were stimulated by and responsive to such materials and deposited significantly more eggs on substrates, including unnatural hosts, that had been treated with aqueous mixtures of bark-canker materials. Stimulation to oviposit occurred even when the female was blinded, indicating the presence of chemical cues. Natural canker-bark extracts immediately stimulated ovipostion and for a few hours significantly increased the number of eggs laid. However, average fecundity was not increased. Antennectomy did not significantly decrease response to volatiles by gravid females, and alternate sites of such chemoreception were not located. Complex mixtures derived by solvent extraction, steam distillation, and volatiles trapping from bark, canker, and gum all had activity. Observations of insect behavior in outdoor cages and also in the laboratory indicated that visual, chemosensory, and mechanosensory receptors are involved in host finding and oviposition.

6.
J Chem Ecol ; 13(1): 99-111, 1987 Jan.
Article in English | MEDLINE | ID: mdl-24301362

ABSTRACT

Hexane and ethanol extracts of seeds from 22 species of plants of the family Meliaceae from a number of countries were prepared. The extracts were submitted to antifeedant and toxicity bioassays utilizing fall armyworm [Spodoptera frugiperda (J.E. Smith)] (Lepidoptera: Noctuidae) larvae and striped cucumber beetle [Acalymma vittatum (F.)] (Coleoptera: Chrysomelidae) adults. Toxicity tests were also performed with brine shrimp,Anemia salina Leach. Feeding inhibition and mortality produced by some of these extracts were comparable to and, in certain cases, slightly greater than the effects produced by comparable neem (Azadiracta indica A. Juss.) seed preparations. Brine shrimp toxicity data do not extrapolate to insect activity, and vice versa.

7.
J Chem Ecol ; 13(11): 2103-14, 1987 Nov.
Article in English | MEDLINE | ID: mdl-24301543

ABSTRACT

Bark volatiles from two peach cultivars (Bisco and Redskin) were obtained by vacuum steam distillation and fractionated by preparative gas chromatography. The fractions were then assayed with the electroantenno- gram (EAG) method on antennae of female lesser peachtree borer [Synanthedon pictipes (Grote and Robinson)]. With both cultivars, two fractions elicited the largest responses. Analysis of this material by GC-MS revealed a complex mixture made up of aromatic alcohols, esters, ketones, and acids, as well as phenols, aliphatic aldehydes, and aliphatic acids. EAG responses to pure samples of all identified components were recorded, and many of these compounds were found to be quite active. Among the most stimulatory were guaiacol, methyl benzoate, and l-phenyl-1,2-propanedione. Also tested were six-carbon aliphatic aldehydes and alcohols which are components of the foliar tissue of most plants. Of these, 1-hexanol showed moderate activity, while the aldehydes and unsaturated alcohols were only weakly active.

9.
Planta Med ; 51(1): 40-2, 1985 Feb.
Article in English | MEDLINE | ID: mdl-17340398

ABSTRACT

Five phytoecdysteroids were isolated from the seeds of DIPLOCLISIA GLAUCESCENS and identified by spectrometric methods ( (1)H-NMR, (13)C-NMR and CIMS). One of them, 24- EPI- makisterone A, has not been reported before. The other four - 20-hydroxyecdysone, makisterone A, 24(28)-dehydromakisterone A and pterosterone - were known previously. The (13)C-NMR spectrum of 24(28)-dehydromakisterone A is presented for the first time.

10.
J Chem Ecol ; 10(2): 301-9, 1984 Feb.
Article in English | MEDLINE | ID: mdl-24318499

ABSTRACT

The sawtoothed grain beetle,Oryzaephilus surinamensis (L.) (Coleoptera: Cucujidae), is attracted to certain volatile components that occur in whole and rolled oats as determined by a laboratory pitfall chamber bioassay. More than 100 components were detected in the attractive carbonyl-containing fractions; 14 of these, making up 60% of the total, were identified and bioassayed. Although hexanal, heptanal, octanal, (E)-2-heptenal, and 2-furaldehyde, at doses ranging variously from 1 to 100 µg, were all significantly attractive, only 1 /10 to 1 /100 as much (E)-2-nonenal or (E,E)-2,4-nonadienal was necessary to produce comparable insect response. In addition, propanal and formaldehyde (previously reported in oats but not detected by us) were bioassayed and found to be attractive.

11.
J Med Chem ; 20(3): 328-32, 1977 Mar.
Article in English | MEDLINE | ID: mdl-845863

ABSTRACT

Twenty-two new esters of natural (-)-cephalotaxine with synthetic acids possessing widely divergent structural features have been synthesized. Murinichloroethyl carbonate (27) esters of cephalotaxine are the most active of this group; this activity is less than that of harringtonine and other naturally occurring cephalotaxine esters. Other synthetic esters exhibiting activity are methyl cephalotaxylfumarate (4) and the trichloroethyl carbonate of cephalotaxyl-L-mandelate (21). The specificity of this experimental tumor system apparently requires esters of (-)-cephalotaxine for tumor inhibition because methyl cephalotaxylitaconate (7b) prepared from the synthetic (+) enantiomer of cephalotaxine is inactive.


Subject(s)
Alkaloids/chemical synthesis , Antineoplastic Agents, Phytogenic/chemical synthesis , Harringtonines/chemical synthesis , Animals , Antineoplastic Agents, Phytogenic/therapeutic use , Esterification , Harringtonines/therapeutic use , Leukemia, Experimental/drug therapy , Leukemia, Lymphoid/drug therapy , Methods , Mice , Mice, Inbred DBA , Stereoisomerism , Structure-Activity Relationship
13.
Cancer Treat Rep ; 60(8): 1157-70, 1976 Aug.
Article in English | MEDLINE | ID: mdl-791485

ABSTRACT

Various phases of research on Ciphalotaxus alkaloids are summarized, including their discovery, nature of antitumor activity, isolation, structural characterization, synthesis, biogenesis, and mechanism of physiologic action.


Subject(s)
Alkaloids/isolation & purification , Harringtonines/isolation & purification , Animals , Chemical Phenomena , Chemistry , Esters , Harringtonines/chemical synthesis , Harringtonines/therapeutic use , Humans , Leukemia L1210/drug therapy , Leukemia, Experimental/drug therapy , Leukemia, Lymphoid/drug therapy , Structure-Activity Relationship
14.
J Med Chem ; 18(1): 63-6, 1975 Jan.
Article in English | MEDLINE | ID: mdl-1109578

ABSTRACT

For further evaluation of structure-activity relationships among the Cephalotaxus alkaloids, a "rearranged" ester (2b) of cephalotaxine was prepared, one which is an isomer of deoxyharringtonine (5a). The parent alkaloid, cephalotaxine (1a), was allowed to react with thionyl chloride to replace its hydroxyl group with chlorine. The resulting chloro compound 1b, on treatment with the silver salt of half ester 6, yielded 2b via an allylic rearrangement followed by further double bond migration. The new "rearranged" deoxyharringtonine isomer 2b proved to be inactive in the P-388 lymphocytic leukemia system and thus further delineated the structural requirements for antitumor activity in this series of alkaloids.


Subject(s)
Alkaloids/chemical synthesis , Antineoplastic Agents/chemical synthesis , Alkaloids/therapeutic use , Animals , Antineoplastic Agents/therapeutic use , Dioxoles/chemical synthesis , Dioxoles/therapeutic use , Isomerism , Leukemia, Experimental/drug therapy , Leukemia, Lymphoid/drug therapy , Magnetic Resonance Spectroscopy , Mass Spectrometry , Mice , Molecular Conformation , Spectrophotometry, Infrared , Stereoisomerism , Structure-Activity Relationship
20.
Lipids ; 3(6): 489-94, 1968 Nov.
Article in English | MEDLINE | ID: mdl-17805802

ABSTRACT

Chemical analysis of a number of sunflower (Helianthus annuus) seed oil samples revealed a low and variable percentage of hydrogen bromide-reactive material. To characterize the compounds responsible for this reactivity, oil was extracted from selected introductions from Uruguay, Turkey, and Yugoslavia that had been subjected to prolonged storage. Two epoxy fatty acids and two conjugated dienolic acids were isolated from the methyl esters derived from these sunflower seed oils by using a combination of column chromatography and countercurrent distribution. The epoxy acids arecis-9,10-epoxystearic acid (0.5%) andcis-9,10-epoxy-cis-12-octadecenoic (coronaric) acid (2.2%). Characterization of the dienols revealed that they are 9-hydroxy-trans-10,cis-12-octadecadienoic acid (1.2%) and 13-hydroxy-cis-9,trans-11-octadecadienoic acid (1.3%). Fresher seed of some of these introductions contained less of the oxygenated components.Oil from recently produced seed of selected high-oil Russian sunflower varieties, including some currently grown in the United States, contained no more than trace amounts of oxygenated acids. Though the relative contributions of genetic and environmental factors toward genesis of oxygenated acids are not established, increase of those acids in some sunflower lines as a result of storage has been demonstrated.

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