Search

Leaf-surface extracts of Nicotiana gossei Domin, N. benthamiana Domin, and N. bigelovii (Torrey) Watson were the most active of those from 17 species of Nicotiana evaluated against late second/early third instars of the greenhouse whitefly, Trialeurodes vaporariorum (Westwood). Four chromatographically purified sucrose esters of N. gossei resulted in 88-94% mortality of late second/early third instars of the sweetpotato whitefly, Bemisia tabaci (Gennadius). A less purified mixture of the four compounds was effective at 1.0 mg/ml (wt:vol) against nymphs of both whitefly species and the green peach aphid, Myzus persicae (Sulzer), and it deterred feeding and oviposition by the twospotted spider mite, Tetranychus urlicae Koch. These sucrose esters were not active against whitefly eggs; neonates of the Colorado potato beetle, Leptinotarsa decemlineata (Say); or second instars of the western flower thrips, Frankliniella occidentalis (Pergande). The selective activity against immature insects, and the feeding and ovipositional deterrence to spider mites suggest pesticidal activity. Activity of 1.0 mglml (wt:vol) aqueous mixtures of the four compounds was comparable with, or better than, label rates of currently available biorational products or pesticides. The purified product was stable for 1 yr.

The use of β-hydroxysilanes to protect olefins during catalytic hydrogenation and deuteration is described. Either (Z)- or (E)- olefins can be stereoselectively regenerated from the key intermediates.

Mixtures of 2,3,6′-tri- O - and 2,3,1′,6′-tetra- O -acylated sucrose esters were isolated as the major nonvolatile components in chromatograp

Isomeric compounds reportedly released by mature males of Nezara viridula as attractants for conspecific females are evidently artifacts formed by dimerization of (E)-4-oxo-2-hexenal. Additional analyses of the male-specific volatiles from Italian, Australian, Brazilian, and Japanese populations of N. viridula verify that at least two distinctive pheromone strains exist, but an active synthetic pheromone has not yet been developed. Analyses of volatiles from N. antennata and Acrosternum aseadum males are also reported showing that the native Japanese Nezara sp., and species in the sister genus Acrosternum, produce species-specific blends based on the same compounds as N. viridula: (Z)-α-bisabolene (1-methyl-4-(1,5-dim ethyl-(Z)-1,4- hexadienyl)-cyclohexene), and trans- and cis-1,2-epoxides of (Z)-α-bisabolene. The trans-/cis- 1,2-epoxide ratio of N. antennata is within the range found for most N. viridula populations, but the blend from Japanese N. viridula males deviates radically from those of other conspecific populations.

Enol esters 3a and 3b, from cyclohexane-1,3-dione and pyrrole-2-carbonyl chloride and indole-2-carbonyl chloride, respectively, rearranged in the presence of triethylamine to the enamino acids 7 and 12. In the presence of cyanide, 3b, also underwent the expected rearrangement to 4b, whereas only 7 was formed from 3a. Treatment of 7 with mercuric acetate in hot acetic acid resulted in decarboxylation and aromatization to phenol 9.

An unusual hemiacetal, cis-3,4-bis[(E)-1-butenyl]tetrahydrofuran-2-ol, the major component of the dorsal abdominal glands of the title insect, was identified by spectral and chemical means, and the structure confirmed by synthesis.

Free and esterified sterols of eggs of the root-knot nematodes Meloidogyne incognita races 2 and 3 and M. arenaria race 1 were isolated and identified by gas-liquid chromatography-mass spectrometry. The major sterols of eggs of each race were 24-ethylcholesterol (33.4-38.8% of total sterol), 24-ethylcholestanol (18.3-25.3%), 24-methylcholesterol (8.6-11.7%), 24-methylcholestanol (7.7-12.5%), and cholesterol (4.6-11.6%). Consequently, the major metabolic transformation performed by Meloidogyne females or eggs upon host sterols appeared to be saturation of the sterol nucleus. The free and esterified sterols of the same race did not differ appreciably, except for a slight enrichment of the steryl esters in cholesterol. Although the sterol composition of Meloidogyne eggs differed from that of other life stages of other genera of plant-parasitic nematodes, the three Meloidogyne races could not be distinguished from each other by their egg sterols. Ecdysteroids, compounds with hormonal function in insects, were not detected by radioimmunoassay in the Meloidogyne eggs either as free ecdysteroids or as polar conjugates.

Three low molecular weight compounds were found in hexane:diethyl ether extracts of fed males of the African ticks, Amblyomma variegatum (tropical bont tick) and A. hebraeum (bont tick), namely, o-nitrophenol, methyl salicylate and 2,6-dichlorophenol. These same compounds were also fond in a rinse of fed A. variegatum males, but were absent or present in only trace amounts in a rinse of fed A. hebraeum males, o-Nitrophenol and methyl salicylate were present in much higher concentrations (i.e., amounts/tick) in A. variegatum than in A. hebraeum. 2,6-Dichlorophenol was also more abundant in A. variegatum than in A. hebraeum, but the differences were not as great as with the former two compounds. Extraction in hexane over a 3-week period revealed four additional compounds, benzaldehyde, benzyl alcohol, benzothiazole and nonanoic acid. The first three compounds were found in males of both species; nonanoic acid was found only in A. hebraeum males. Published reports consistently show strong attraction by o-nitrophenol and methyl salicylate for both sexes of the two bont tick species; 2,6-dichlorophenol and benzaldehyde have been reported to be attractive to both sexes of A. hebraeum. The possible roles of these compounds, as well as others occasionally reported from A. hebraeum and A. variegatum, as components of the aggregation/attachment pheromone or other pheromones is discussed.

Enol esters 3a and 3b, from cyclohexane-1,3-dione and pyrrole-2-carbonyl chloride and indole-2-carbonyl chloride, respectively, rearranged in the presence of triethylamine to the enamino acids 7 and 12. In the presence of cyanide, 3b, also underwent the expected rearrangement to 4b, whereas only 7 was formed from 3a. Treatment of 7 with mercuric acetate in hot acetic acid resulted in decarboxylation and aromatization to phenol 9.

Male predaceous stink bugs (Pentatom idae: Asopinae) in the genus Podisus release longrange attractant pheromones from a pair of hypertrophied glands opening underneath the wings. Pherom one com positions are reported for four additional Podisus spp.: two Neotropical species (P. connexivus and an undetermined Podisussp.), and two Nearctic species (P. placidus and P. mucronatus). Males of each species release (E)-2-hexenal, plus species-specific major components that include α-terpineol, linalool, 9-hydroxy-2-nonanone, and (E)-2-hexenyl tiglate. The pheromonal chemistry of the Neotropical species closely resembles that for the previously studied Nearctic species, P. macuiiventris and P. fretus.

An ecdysteroid RIA was used to determine the ecdysteroid titer in developing embryos of Dysdercus fasciatus and revealed that peak titer occurred approximately 120 h post-oviposition. Analysis of neutral sterols at this time indicated sitosterol to be the predominant neutral sterol with lesser amounts of campesterol. Embryonic sterols were highly reflective of the sterols found in the cotton seed diet upon which previous generations of the bugs had fed. Analysis of the embryonic extract for ecdysteroids indicated the presence of both makisterone A and the 29-carbon ecdysteroid makisterone C. Isolation of these compounds was accomplished by reversed-phase and silica HPLC in conjunction with RIA, and the identification of both compounds was confirmed by mass spectrometry. No ecdysone or 20-hydroxyecdysone was detected in the embryonic sample.

The so-called scentless plant bugs are actually exceptionally redolent insects. Twenty-two volatile exocrine compounds were identified from eight rhopalid species, including monoterpene hydrocarbons and alcohols, alkenals and ketoalkenals, 2-phenylethanol and (4S,5S)-(+)-5-hydroxy-4-decanolide. The lack of species-specificity for the exocrine blends from eastern and western boxelder bugs ( Boisea trivittatus and B. rubrolineatus , respectively) cast doubt on their validity as separate species. The biological roles for the array of exocrines released by rhopalids are largely unknown, but potentially important because boxelder bugs are an increasing urban nuisance and species such as Niesthrea Iouisianica may be useful weed control agents.

A comparison of sterol utilization by 3 stored-products insects revealed very different capabilities. The fluor beetle,Tribolium castaneum dealkylates and converts dietary sitosterol to about equal amounts of cholesterol (43.7%) and 7-dehydrocholeterol (39.8%), whereas another flour beetle,Tenebrio molitor, produces considerably less 7-dehydrocholesterol (16.8%) and relatively more cholesterol (66.7%) from sitosterol. The lepidopteran,Plodia interpunctella, utilized dietary sterol very similar to plant-feeding lepidoptera, producing primarily cholesterol (86.5%) from sitosterol.

Males of the Central American stink bug species,Euschistus obscurus, produce an attractant pheromone composed of a blend of compounds characteristic of North AmericanEuschistus spp. and the South American soybean pest,E. heros. The range ofE. obscurus extends into the southern United States, the species is easy to rear, and males produce an exceptionally large quantity of pheromone (>0.5µg/day/male). These factors madeE. obscurus useful for characterizing the novel pheromone components ofE. heros without importing this pest species into the United States.Euschistus obscurus males produce methyl (2E,4Z)-decadienoate (61 %) in abundance, which is characteristic of North American species, and methyl 2,6,10-trimethyltridecanoate (27%), the main male-specific ester ofE. heros. The chirality ofEuschistus spp. methyl-branched esters, and field activity of synthetic formulations, remain to be determined.

Aeration and exocrine gland extracts were analyzed for three Coreidae and two Alydidae. Males of all the species studied emit volatile blends that are probably pheromones, but sexual communication in these insects evolved differently. In the alydids,Riptortus serripes andMirperus scutellaris, the metathoracic scent glands are sexually dimorphic, and the dimorphisms are expressed chemically. Secretions from the male alydids contain high concentrations of esters or alcohols [e.g., (E)-2-hexenyl (Z)-3-hexenoate, (E)-2-hexenyl butyrate, and (E)-2-octenol], while females produce mainly acids and aldehydes [e.g., butyric and hexanoic acids, and (E)-2-hexenal]. In the coreids,Amblypelta lutescens lutescens, Amblypelta nitida, andLeptoglossus phyllopus, the metathoracic scent glands are not sexually dimorphic, but male- and species-specific volatiles are released, apparently from cells in the cuticular epidermis. The coreid male-specific volatiles are primarily monoterpenes and sesquiterpenes, including (−)-(3R)-(E)-nerolidol as the major component fromA. lutescens lutescens (an Australasian species) andL. phyllopus (a Nearctic species). Only (+)-(3S)-(E)-nerolidol is commonly found in plants so (E)-nerolidol from these coreids is environmentally unique because of its chirality.

The hawthorn lace bug,Corythucha cydoniae, and the eggplant lace bug,Gargaphia solani, possess alarm pheromones that are produced in dorsal abdominal glands (DAGs). WhenG. solani nymphs are grasped, they emit secretion from both DAGs; the posterior DAG secretion alone elicits alarm, but the anterior DAG secretion may hasten the response. InC. cydoniae, the response is due to a synergism between the anterior and posterior DAG secretions, and nymphs are apparently unable to voluntarily release their DAG secretions; both DAGs must be ruptured for the pheromone to escape. The alarm pheromones are interspecifically active in patterns matching the intraspecific activities. Compounds identified from tingid DAG secretions that are involved in the alarm messages are: (E)2-hexenal, (E)-4-oxo-2-hexenal, acetaldehyde, geraniol, and linalool. A new natural product of unknown function (designated nerolidol aldehyde) was identified from the anterior DAG secretions of both species.

In the nearctic predaceous stink bugs (Asopinae), Perillus bioculatus and Stiretrus anchorago, and the neotropical asopine, Oplomus severus, males possess conspicuous sternal glands that are absent in females. In each of these species, the male sternal gland secretion contains predominantly a single compound; 6,10,13-trimethyltetradecyl isovalerate in the allopatric species, P. bioculatus and O. severus, and 6,10,13-trimethyltetradecanol in S. anchorago, a species sympatric with P. bioculatus. The function of the sternal gland secretions from asopine hemipterans is unknown.

The levels of individual free and conjugated ecdysteroids and ecdysteroid acids, labeled from [14C]cholesterol, in five different age groups of male Manduca sexta during pupal-adult development were determined by HPLC. Eight free ecdysteroids, eight ecdysteroid phosphates, and two ecdysteroid acids were identified. Newly ecdysed pupae contained predominantly 3-epiecdysteroids in each of the free, conjugated, and acidic ecdysteroid fractions. The titer of each ecdysteroid fraction rose sharply by day 4, and this was particularly noteworthy with respect to free ecdysone and 3-epi-20-hydroxyecdysonoic acid. This stage demonstrated high degrees of ecdysone biosynthesis, oxidative catabolism, and phosphorylation. As development proceeded to day 16, total ecdysteroid titer remained constant; a decreasing free ecdysteroid titer was accompanieid by increasing titers of both conjugates and acids resulting from the metabolic processes of hydroxylation, oxidation, epimerization, and phosphorylation. The predominant metabolites throughout development were 3-epi-20-hydroxyecdysonoic acid and the phosphate conjugates of 3-epi-20-hydroxyecdysone and 3-epi-20,26-dihydroxyecdysone. The ultimate inactivation of the ecdysteroids of M. sexta during pupal-adult development is possibly mediated by two pairs of metabolically-linked processes, one leading to a 3-epiecdysteroid acid, and the other to 3-epiecdysteroid phosphates.

Makisterone A , a 28-carbon moulting hormone, has been identified as the major free pupal ecdysteroid in the honey bee, Apis mellifera. The pupal ecdysteroid was isolated and identified by normal and reversed-phase high performance liquid chromatography in conjunction with a radioimmune assay. The compound was further characterized physico-chemically by both mass spectrometry and nuclear magnetic resonance spectroscopy. No C27 ecdysteroids (i.e. 20-hydroxyecdysone or ecdysone) were detected at this stage of development. This is the first isolation and identification of a 28-carbon ecdysteroid in an insect species from the order Hymenoptera. Utilization of dietary sterols by honey bees is also discussed.

Racemic 6,10,13-trimethyl-1-tetradecanol has been synthesized. Successive elaboration of the molecule using 5-methyl-2-hexanone as the carbon-terminal fragment gave the desired alcohol in a 4% overall yield over 13 steps. Neglecting stereochemistry, the product was shown to be identical to the alcohol previously identified from the sternal glands of maleStiretrus anchorago. It attracts both adult sexes and larvae of this insect in the field, confirming its postulated identity as an aggregation pheromone. The corresponding aldehyde is more than 10 times more concentrated in airbornetrapped samples (5-7% by gas chromatography) than in extracts of glandular setae (0.4-0.5%). This alcohol or its isovalerate ester has been found in other predaceous pentatomids, providing further evidence for pheromones in these species.

The cuticular alkenes of the female stable fly,Stomoxys calcitrans (L), which were responsible for inducing male fly copulatory behavior are (Z)-9-hentriacontene, (Z)-9-tritriacontene, 13-methyl-1-hen-triacontene and 13-methyl-1-tritriacontene. The identifications of the branched alkenes and the synthesis of these four compounds are described. Bioassays indicate that these materials in combination with previously described methyl branched alkanes are more active than the individual components.

The sterols of six species of Hymenoptera including two phytophagous species (Apis mellifera and Megachile rotundata) and four omnivorous species (Dolichovespula maculata, Vespula maculifrons, Formica exsectoides, and Solenopsis invicta) were isolated and identified. The two phytophagous species of bees have in common relatively high levels of 24-methylenecholesterol and very low levels of cholesterol (

Extracts of three continuous cell lines from the cabbage looper, Trichoplusia ni, were assayed for the presence of ecdysteroids. While no evidence of ecdysteroids was present in the extracts of the ovarian (TN-368) or embryonic (IPLB-TN-R2) cell lines, radioimmunoassays on extracts of media and extracts of cell pellets from imaginal disc cell cultures (IAL-TND1) were positive. The immunoreactive material from both cells and media co-migrated with a 20-hydroxyecdysone standard on reversed-phase high-performance liquid chromatography (HPLC). The immunoreactive fractions from the cell extract were chromatographed on silica HPLC and subjected to mass spectral analysis. Both of these analyses indicated that the unknown compound was 20-hydroxyecdysone. Radioimmunoassay indicated up to 28 ng of ecdysone equivalents in cells (3.75 x 107 cells) from 50 ml of IAL-TND1 cultures, which is equivalent to 120 ng of 20-hydroxyecdysone based on relative reactivity of the antiserum used in this study. This report presents the first evidence of 20-hydroxyecdysone production by a continuous insect cell line and also the first to show that cells from imaginal discs are capable of ecdysteroid synthesis.

Lipids comprising the stenols, stanols, polar lipid fatty acids, alkanes and alkenes of blue-green algal-(diatomaceous)-microbial mats and cores (modern cold water stromatolites) collected from three Antarctic lakes were identified and compared with those of other algae. The major stenols were: (cholesta-5, 22-dien-3β-ol, cholest-5-en-3β-ol, 24-methylcholesta-5, 22-dien-3β-ol, 24-methyl-cholest-5-en-3β-ol, 24-ethylcholesta-5, 22-dien-3β-ol, and 24-ethylcholest-5-en-3β-ol). The presence of C28 Δ3, 22 stenols, as well as other C28 stenols, was suggestive of diatom input. C29 stenols may have originated from blue-grern algae. However, the high concentrations of stenols present and the lack of Δ7 stenols was atypical for known stenol components of several blue-green algal species previously reported. The occurrence of these stenols and other lipid markers strongls implicate diatoms as well as blue-green algae as important biogenetic sources of lipids and has established the potential for studies of lipid diagenesis in these unique cold, freshwater stromatolites.

Following injection into female Manduca sexta pupae, [14C]cholesterol is converted to a radiolabeled C21 nonecdysteroid conjugate as well as ecdysteroid conjugates, which in ovaries and newly-laid eggs consist mainly of labeled 26-hydroxyecdysone 26-phosphate. During embryogenesis, as the level of 26-hydroxyecdysone 26-phosphate decreases there is a concurrent increase in the amount of a new, labeled ecdysteroid conjugate. This conjugate, which is the major ecdysteroid conjugate (9.4 μg/g) in 0- to 1-hour-old larvae was identified as 26-hydroxyecdysone 22-glucoside by nuclear magnetic resonance and chemical ionization mass spectrometry. This is the first ecdysteroid glucoside to be identified from an insect. The disappearance of 26-hydroxyecdysone 26-phosphate in 0- to 1-hour-old larvae indicates that the 26-hydroxyecdysone 22-glucoside is derived from 26-hydroxyecdysone 26-phosphate. 3-Epi-26-hydroxyecdysone was the major free ecdysteroid isolated from these larvae and 3-epi-20,26-dihydroxyecdysone was the next most abundant ecdysteroid isolated. Interestingly, the 0- to 1-hour-old larvae contained the highest levels of 3α-ecdysteroids per gram of insect tissue (8.7 μg/g) to be isolated from an insect, yet there was a complete absence of the corresponding free 3β-epimers. The ecdysteroid conjugate profiles of ovaries and 0- to 1-hour-old larvae are discussed. Methodology is presented that permits the efficient separation of free and conjugated ecdysteroids and nonecdysteroid conjugates (C21-steroid conjugates).

The metabolism of three dietary 4,4-desmethylsterols and two 4 alpha-methylsterols was investigated in the free-living nematode Caenorhabditis elegans. Dietary cholestanol was converted mostly to lathosterol. Dietary lathosterol, 7-dehydrocholesterol, 4 alpha-methylcholest-7-enol and 4 alpha-methylcholest-8(14)-enol each remained largely unchanged. An absolute requirement for a substantial quantity of 7-dehydrocholesterol in C. elegans did not exist. C. elegans was unable to remove a 4 alpha-methyl group or introduce a double bond at C-5 and also demonstrated the lack of a delta 7-reductase. Its nutritional sterol requirement was satisfied by cholestanol, lathosterol or 7-dehydrocholesterol; growth was comparable to that obtained previously in media containing delta 5-sterols. However, the two 4 alpha-methylsterols appeared to be unsatisfactory sterol nutrients. The possible physiological importance of 4 alpha-methylsterols is discussed briefly.

Panagrellus redivivus was propagated in media containing three structurally different sterols: 7-dehydrocholesterol, campesterol or stigmastanol. Nematodes propagated with 7-dehydrocholesterol contained mostly lathosterol and 7-dehydrocholesterol. Nematodes propagated with campesterol contained mostly cholesterol and cholestanol. Nematodes propagated with stigmastanol contained mostly cholestanol. The sterol ester fraction was enriched with 4α-methylsterols and contained the same sterols as the free sterol fraction except for nematodes propagated with 7-dehydrocholesterol, where no dietary sterol was found in the ester fraction.P. redivivus is capable of reducing the Δ5-bond, C−24 dealkylation and methylating the sterol nucleus at C−4.

Column chromatography of the pentane extract of freeze-dried cotton buds or anthers yielded a wax-sterol ester fraction that exhibited potent feeding stimulant activity for the cotton boll weevil. The waxes of the wax-sterol ester mixture were responsible for the feeding activity. Saponification of the wax-sterol ester fraction yielded about 15% alcohols and 85% sterols. A C18∶1 alcohol, dihydrophytol, phytol, and geranylgeraniol constituted 15, 36, 26, and 23%, respectively, of the total alcohols, implicating certain of their long-chain esters as feeding stimulants. Several esters of dihydrophytol, phytol, and geranylgeraniol were identified among the waxes by GC-MS. Certain phytol, geranylgeraniol, and oleyl alcohol esters containing C12 to C26 acid moieties were synthesized and were found to induce high feeding stimulant activity in the cotton boll weevil.

Capillary gas liquid chromatography analyses were conducted on free and esterified sterol fractions of cotton (Gossypium hirsutum cv. Stoneville 213) floral buds and anthers. The free sterols of both cotton buds and anthers consist mainly of the common plant sterols sitosterol, stigmasterol and 24ζ-methylcholest-5-en-3β-ol. The composition of esterified sterols of cotton buds and anthers were similar, and consisted of pollinastanol, 31-norcycloartanol, cycloartenol, 31-norcycloartenol, 24-dehydropolinastanol and sitosterol. Desmosterol was also present in both the free and esterified sterols of anthers. The identities of the sterols were confirmed by gas chromatography-mass spectrometry analyses. Esterified sterols accounted for 46.7 and 88.7% of total sterols of cotton bud and anthers, respectively. The ratio of esterified sterol to free sterol per gram of tissue is about 8∶1 in anthers. The Δ5-sterols of the esterified sterols of cotton buds and anthers account for only 17 and 9.2% of the total sterols, respectively.

Last-stage nymphs of the broad-headed bug, Megalotomus quinquespinosus contain the C28 ecdysteroid makisterone A as their major ecdysteroid. No ecdysone or 20-hydroxyecdysone was detected in whole body extracts analyzed by high performance liquid chromatography and radioimmune assay. Analyses of the neutral sterols of this phytophagous hemipteran revealed that the sterol composition of the nymphs was highly reflective of their dietary sterols. The most abundant nymphal sterols were sitosterol (46.6%), Δ7-stigmastenol (13.8%) and spinasterol (13.4%). Cholesterol accounted for only 0.2% of the total sterols and indicates that this species is incapable of converting 24-alkyl sterols to cholesterol.

Sexually mature males of the sourthern green stink bug, N. viridula, release a pheromone attractive in the field to conspecific females, males, and late-stage larvae and to the parasitoid Trichopoda pennipes (Diptera: Tachinidae). The pheromone blend typically includes (Z)-α-bisabolene (17%), trans- and cis-1,2-epoxides of (Z)-α-bisabolene (44 and 15%, respectively), (E)-nerolidol (1.4%), and n-nonadecane (7.4%). The existence of Nezara pheromone strains, first suggested by differential Trichopoda parasitization of geographically isolated N. viridula populations, has been chemically verified.

Chromatograms of the cuticular lipids washed from recently emerged female and maleFannia canicularis (L.) flies were nearly identical, but by the time the flies were 5 days old, the cuticular components of the two sexes differed considerably. A monoolefin which constituted 66% of the cuticular lipid from 5-day-old females stimulated a copulatory response from males and was identified as (Z)-9-pentacosene. The cuticular lipid of the same age males contained only 1% of this compound. Although all the major constituents of the cuticular lipid from mature females were hydrocarbons, 27% of the lipid washed from 5-day-old males was a nonhydrocarbon material that was represented by a single GLC peak. This material was identified as heneicosan-8-ol acetate.

Nymphs of the rhododendron lace bug produce from specialized setae a liquid secretion from which a number of related acetogenins have been identified. Two (2,6-dihydroxyphenyl)-1,3-diketones are the principal components and are accompanied by the corresponding chromones as well as by chromones bearing an additional phenolic oxygen.

Two of the title compounds, recently identified as components of exudates produced by lace bug nymphs of the genus Corythucha , have been synthesized. 2-Acyl-3-hydroxy-2-cyclohexen-1-ones were converted to 3-alkyl-6,7-dihydro-1,2-benzisoxazol-4(5H)-ones which were hydroxylated at position 5, then reductively disassembled. Sodium borohydride and nickel chloride in DMF/THF containing 1-octene selectively reduced the isoxazole N-O bond without hydrogenating a side chain double bond.

It is confirmed from a literature review and new research that different pheromone strains exist in Nezara viridula from different geographical regions and that males from the sister genus Acrosternum emit bouquets of distinctive ratios of the same sesquiterpenes as in N. viridula. Many tachinid parasitoids use heteropteran pheromones as kairomones, and it is suggested that the chemical similarity of pheromones of N. viridula and Acrosternum has facilitated the adoption of N. viridula as a host by tachinids in the New World.

Drosophila melanogaster was unable to dealkylate and convert [14C]sitosterol to cholesterol and no evidence was found for conversion of [14C]desmosterol to cholesterol. Therefore,D. melanogaster is incapable of dealkylating and converting C28 and C29 phytosterols to cholesterol.

Following injection into Manduca sexta (L.) female pupae (day 16), [14C]cholesterol was converted to a C21 steroid conjugate, 5-[14C]pregnen-3 beta,20 beta-diol glucoside. The conjugate was isolated from ovaries and eggs and contained three glucose units at least one of which is attached to C-20. The distribution of the other two glucose units remains to be determined. Other than the dealkylation of C-24 alkane or alkene substituents, side-chain cleavage of sterols is uncommon to insects. Here we report the first definitive proof of the biosynthesis of a C21 steroid conjugate from cholesterol in an insect species. The capability of M. sexta to so readily convert cholesterol to a C21 steroid suggests a physiological role for 5-pregnen-3 beta,20 beta-diol in this species.

Males ofPodisus fretus (Hemiptera: Pentatomidae) release a long-range attractant pheromone containing linalool (49.0%), (E)-2-hexenal (34.5%), benzyl alcohol (12.0%), nerolidol (2.0%),α-terpineol (1.1%), and traces of several other compounds. The eastern yellowjacket,Vespula maculifrons (Hymenoptera: Vespidae), is attracted to artificial pheromones forP. fretus and for the sympatric species,Podisus maculiventris.

Following injection into Manduca sexta (L.) female pupae (day 16), [14C]cholesterol was converted to a C21 steroid conjugate, 5-[14C]pregnen-3 beta,20 beta-diol glucoside. The conjugate was isolated from ovaries and eggs and contained three glucose units at least one of which is attached to C-20. The distribution of the other two glucose units remains to be determined. Other than the dealkylation of C-24 alkane or alkene substituents, side-chain cleavage of sterols is uncommon to insects. Here we report the first definitive proof of the biosynthesis of a C21 steroid conjugate from cholesterol in an insect species. The capability of M. sexta to so readily convert cholesterol to a C21 steroid suggests a physiological role for 5-pregnen-3 beta,20 beta-diol in this species.

The diaphragm, longissimus, psoas major, semitendinosus and transversus abdominus muscles from eight or nine Angus steers were evaluated at each age of slaughter including 12, 18, 24, 30, 36, 48, 60 and 72 mo. The content of K, Fe, and Zn varied (P less than .01) with age of the steers. Ca, Na and Mg were not affected. The K content on a fat-free basis decreased from a high of 392 mg/100 g wet tissue at 24 mo of age to a low of 332 mg/100 g at 72 mo. Fe content increased with age from 2.00 mg/100 g of tissue at 12 mo to 3.73 mg/100 g at 72 mo. Concentrations of all minerals varied (P less than .01) among the five muscles evaluated. Feeding regimen had a significant effect on K, Fe and Zn, Steers fed entirely ad libitum had a higher K (17 mg/100 g more) and Fe (.19 mg/100 g more) content in their muscles than did the steers that were fed to gain .45 kg/d or those fed ad libitum for the last 6 mo before slaughter. Where significant, the magnitude of the difference in mineral content among age groups, muscles and feeding regimens was large enough to require that maturity, muscle and feeding regimen be specified when values for mineral content were reported.

The azalea lace bug secretes a clear fluid from secretory setae on the antennae and globulated spines on the dorsal and lateral aspects of the abdomen. The secretion contains 2-alkyl-5-hydroxychromones, the corresponding chromanones and diketones, and straight-chain aldehydes and ketones.

Two of the title compounds, recently identified as components of exudates produced by lace bug nymphs of the genus Corythucha , have been synthesized. 2-Acyl-3-hydroxy-2-cyclohexen-1-ones were converted to 3-alkyl-6,7-dihydro-1,2-benzisoxazol-4(5H)-ones which were hydroxylated at position 5, then reductively disassembled. Sodium borohydride and nickel chloride in DMF/THF containing 1-octene selectively reduced the isoxazole N-O bond without hydrogenating a side chain double bond.