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Saw flies

The oxazoline methodology can be applied in the total synthesis of natural products. For example, in the course of the total synthesis of European pine-saw fly pheromone 47, the key intermediate, chiral a-methyl carboxylic acid 46, was prepared via the reaction of a-lithioethyloxazoline with n-octyl iodide. The product 2-methyl decanoic acid 46 was obtained, after hydrolysis, in 72% ee (Scheme 2-26).51... [Pg.92]

Such routes have been used for the synthesis of natural products terpenes such as egomaketone (3-(4-methyl-3-pentenoyl)furan, perillene, ar-turmerone and iso-ar-turmerone [341], ar-curcumene [152], artemisia and isoartemisia ketones [342, 343], damascone [344], macrolides such as maysine [345], and pheromones with the sex attractant of the pine saw-fly [346],... [Pg.56]

During the pine saw-fly pheromone synthesis based on thiophilic addition it was shown that high enantio- and diastereoselectivity were observed in the reduction of p-ketodithioesters with baker s yeast, affording new and useful chiral synthons [346]. [Pg.57]

Butthat s notthe religious I m talking about. Organic seems to fire up the apocalyptic in us—religion in the future tense. Americans love to see things in these terms. It s been a pretty common reaction ever since the Puritans first looked into the misty colonial woods of America s seventeenth century and saw flying devils. [Pg.238]

Some of the pests in question included the "pine looper moth, pine beauty, pine moth. Nun moth, saw flies, bark beetles, pine needle cast fungus, pine bluster rust, honey fungus, red rot (Maser, The Redesigned Forest, p. 78). [Pg.362]

Branches defoliated. Cause Larch saw-flies. In June, the small, wasplike adults lay eggs in the side of larch shoots, causing shoots to twist. These /z -l", grayish green, caterpillarlike larvae emerge about a week later. They feed on the leaves, starting with lower branches. Remove debris, which provides an overwintering site for the pest, from around trees. Spray shoots with superior oil to control heavy populations. [Pg.132]

Lactones have similar reactivity to ketones and at low temperature one molecule of an alkyl-lithium may give the ketone in good yield. In his synthesis of the pine saw fly sex attractant 43, Magnusson19 chose to replace the more-or-less central methyl group by a double bond 44 so that disconnection to a ketone 45 was possible. [Pg.118]

Ketones with useful heteroatomic functional groups containing nitrogen 199 2121, oxygen[163, 213 2171, phosphorus12181 and sulfur11 4, 18+1 219-2271 have been reduced by biocatalysts. For example, an intermediate in the synthesis of p-lactam antibiotics was obtained by microbial reduction of a P-keto ester as shown in Fig. 5-39(a)(1991, while yeast reduction of a p-keto dithioester afforded an easily separable mixture of p-hydroxy-dithioesters, the major component of which was converted enantiose-lectively into a sex attractant of the pine saw-fly as shown in Fig. 15-39(b)12191. [Pg.1028]

Modified Wittig reaction. The reaction of methylenetriphenylphosphorane (prepared in situ from methyltriphenylphosphonium bromide and -butyllithium) with the hydroxy ketone 1 in ether is markedly improved by addition of 3 equiv. of HMPT. As the reaction proceeds, a complex of LiBr and HMPT separates from the ether solution. Probably the Wittig reaction becomes salt free, with enhancement of the rate and increase in yield from 24 to 66%. The product (2) is converted by hydrogenation into er> //rro-3,7-dimethylpentadecane-2-ol, esters of which are sex attractants of pine saw flies. ... [Pg.127]

C,7Ha60, Mr 256.47, [aJo -11.8° (neat). The most important structural element in the sex pheromone of saw-flies of the genera Diprion and Neodiprion. Mixtures of diastereoisomers of the acetate or propanoate form the species-specific pheromones of these insects. [Pg.190]

Canola/oilseed rape Aphids Flea beetle Saw fly... [Pg.1008]

Viral diseases have been isolated from several hundred insect species (1). Although these viruses represent several families, those studied for use as control agents are almost exclusively limited to occluded viruses (nuclear polyhedrosis [NPV] and granulosis [GV]) of Baculoviridae. Known occluded baculoviruses are mostly restricted to larvae of Lepidoptera and Hymenoptera (saw-flies), thus limiting viral insecticide development primarily to these two orders. These viruses are safe (2, 3), virulent, efficaceous (4) and can be produced in quantity in insect hosts. [Pg.384]


See other pages where Saw flies is mentioned: [Pg.43]    [Pg.94]    [Pg.162]    [Pg.47]    [Pg.1028]    [Pg.44]    [Pg.162]    [Pg.226]    [Pg.230]    [Pg.50]    [Pg.269]   
See also in sourсe #XX -- [ Pg.269 ]




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