3675-00-1Relevant academic research and scientific papers
Identification and synthesis of male-produced sex pheromone components of the stink bugs: Chlorochroa ligata and Chlorochroa uhleri
Ho, Hsiao-Yung,Millar, Jocelyn G.
, p. 2067 - 2095 (2001)
The reproductive behaviors of the stink bugs Chlorochroa ligata and C. uhleri were studied in the laboratory. Adults of both species became sexually mature about 12-14 days after the final molt, and both sexes mated multiple times during their lifetimes. The mean duration of copulation was 54 ± 24 min for virgin bugs and 46 ± 33 min for experienced bugs for C. ligata and 78 ± 55 min for field-collected C. uhleri of unknown mating status. Male C. ligata were found to transfer a significant fraction of their body mass (19%) to females during mating. Sexually mature C. uhleri males produced three sex-specific compounds, methyl (R)-3-(E)-6-2,3-dihydrofarnesoate, methyl (2E,6E)-farnesoate, and methyl (E)-5-2,6,10-trimethyl-5,9-undecadienoate, in a ratio of 100:0.9:0.6. These three compounds were also produced by sexually mature male C. ligata in a ratio of 100:0.5:0.4. Identifications of the compounds were confirmed by synthesis. Production of the male-specific compounds peaked in late afternoon to early evening, coincident with the peak period of reproductive activity. Laboratory and field bioassays demonstrated that female bugs were attracted to odors from live males and to reconstructed blends of the male-specific compounds.
Juvenile hormone agonists affect the occurrence of male Daphnia
Tatarazako, Norihisa,Oda, Shigeto,Watanabe, Hajime,Morita, Masatoshi,Iguchi, Taisen
, p. 827 - 833 (2003)
The water flea Daphnia magna reproduces primarily by cyclic parthenogenesis. Environmental stimuli that signal a change to adverse conditions induce the organisms to switch from parthenogenesis to gamogenetic reproduction. During the gamogenetic period, they produce male daphnids and dormant resting eggs, which can survive prolonged periods of environmental adversity. However, little is known about the mechanisms associated with the switch from parthenogenesis to gamogenetic reproduction. We investigated the effects of several juvenoids on sex determination in Daphnia. Females less than 24 h old were exposed to various concentrations of the test substance and were observed for 21 days. It was found that they can trigger the appearance of male daphnids: the percentage of males in the population increases to a level greater than what occurs under ordinary environmental conditions. We found that methylfarnesoate, juvenile hormone III, methoprene, and the phenoxyphenoxy derivatives pyriproxyfen and fenoxycarb (both insecticides) reduced the production of offspring and produced sex ratios dominated by male daphnids. Pyriproxyfen and fenoxycarb showed striking effects at low concentrations. Exposure to either of these chemicals at a concentration of 330 ngl -1 caused adult females to produce almost all male neonates. Methylfarnesoate, juvenile hormone III, and methoprene showed an effect in inducing male production at higher concentrations (3.7×103, 3.3×105, and 1.3 ×105 ngl-1, respectively). Our findings suggest that juvenile hormone agonists, including some insecticides, affect the chemical signaling responsible for inducing the production of male offspring.
Determination of the regiochemistry of insect epoxide hydrolase catalyzed epoxide hydration of juvenile hormone by 18O-labeling studies
Linderman, Russell J.,Walker, Elizabeth A.,Haney, Carol,Roe, R. Michael
, p. 10845 - 10856 (1995)
The regiochemistry of Trichoplusia ni epoxide hydrolase catalyzed epoxide hydration of insect juvenile hormone (JH) III has been determined by GC/MS studies of 18O-label incorporation. Nucleophilic addition occurs at C10 of the C10,11 epoxide of JH III. The identification of isotopically labeled and unlabeled diol from the enzyme catalyzed hydration reaction in H218O implies that a covalently bound ester intermediate may be involved in the mechanism of the reaction.
Superacidic cyclization of higher terpenoid acids and their esters
Vlad, P. F.,Ungar, N. D.,Tuen, Nguen Van
, p. 2404 - 2411 (1995)
The superacidic cyclization of aliphatic and partially cyclized C15-C25 terpenoid acids and their esters proceeds structure-selectively and stereospecifically, affording α-isomers of completely cyclized epimeric β,γ-unsaturated acids or esters; the configuration of their carboxylic or ester groups is predetermined by the configuration of the double bond conjugated with the carboxyl or ester groups in the starting compounds. - Key words: terpenoids; acids; esters, superacidic cyclization, selectivity.
Convenient synthesis of deuterium labelled sesquiterpenes
Duhamel, Nina,Martin, Damian,Larcher, Roberto,Fedrizzi, Bruno,Barker, David
supporting information, p. 4496 - 4499 (2016/09/14)
Sesquiterpenes are an important class of molecules, with roles ranging from pollination and signalling to defense mechanisms. Despite their apparent importance, the limited number of commercial standards has hindered their study and precise quantification. Herein, we report the syntheses of fourteen labelled sesquiterpenes with a high level of deuterium incorporation (>95%) for applications in MS-based studies.
UNIQUE HALOGEN-INDUCED CYCLIZATIONS, REAGENTS THEREFOR, AND COMPOUNDS PRODUCED THEREBY
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Page/Page column 116, (2012/04/04)
This disclosure is related to halonium compounds useful for cyclization of polyenes, alkenoic acids, and alkenyl alkyl ethers, and halogenation of aromatic compounds. The synthesis of such halonium compounds, compounds made using such halonium compounds, and synthesis of natural compounds, including decalins, using the halonium compounds is also disclosed. A representative halonium compound of the disclosure is: Formula (I).
Niaviolides, new macrocyclic sesquiterpenes secreted by males of the African butterfly Amauris niavius
Stritzke, Katja,Schulz, Stefan,Boppre, Michael
, p. 1337 - 1342 (2007/10/03)
The abdominal androconial organs ("hairpencils") of the African butterfly Amauris niavius (Danainae) emit a complex scent bouquet consisting of previously described aromatic compounds, terpenoids, fatty acids, and hydrocarbons. This work reports the identification of two major sesquiterpenes, each possessing a unique 13-membered macrolide ring, originating from an α,ω-oxidation pattern of the sesquiterpene backbone. To the best of our knowledge, sesquiterpene macrolides have not been found before in nature. The structure elucidation of the two compounds, which we propose to call niaviolide (3) and epoxyniaviolide (4), by NMR and GC/MS experiments is presented, together with their subsequent synthesis. Finally, the absolute configuration of natural 4 was determined to be (S,S) by stereoselective synthesis and chiral gas chromatography. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
Evaluation of morphogenic regulatory activity of farnesoic acid and its derivatives against Candida albicans dimorphism
Kim, Sanghee,Kim, Eunkyung,Shin, Dong-Sun,Kang, Heonjoong,Oh, Ki-Bong
, p. 895 - 898 (2007/10/03)
A series of farnesoic acid derivatives was prepared and their morphogenic regulatory activities were evaluated. Their inhibitory activities against yeast cell growth and yeast-to-hypha transition examined in Candida albicans cells are dependent upon the chain length as well as the substitution patterns on the isoprenoid template. The preliminary structure-activity relationship of these compounds is described to elucidate the essential structural requirements.
Synthesis and enzymatic cyclization of (3S)-14-fluoro-2,3-oxidosqualene
Robustell, Brian J.,Abe, Ikuro,Prestwicht, Glenn D.
, p. 9385 - 9388 (2007/10/03)
A convergent asymmetric synthesis led to (3S)-14-fluoro-2,3- oxidosqualene (14-FOS, 16), which was cyclized by bacterial squalene:hopane cyclase to a monocarbocyclic product with a bridged ether and a 2:3 mixture of bicyclic alcohols. 14-FOS was neither a
Substrate specificity for the epoxidation of terpenoids and active site topology of house fly cytochrome P450 6A1
Andersen, John F.,Walding, Jennifer K.,Evans, Philip H.,Bowers, William S.,Feyereisen, Rene
, p. 156 - 164 (2007/10/03)
Heterologous expression in Escherichia coli, purification, and reconstitution of house fly P450 6A1 and NADPH-cytochrome P450 reductase were used to study the metabolism of terpenoids. In addition to the epoxidation of cyclodiene insecticides demonstrated previously [Andersen et al. (1994) Biochemistry 33, 2171-2177], this cytochrome P450 was shown to epoxidize a variety of terpenoids such as farnesyl, geranyl, and neryl methyl esters, juvenile hormones I and III, and farnesal but not farnesol or farnesoic acid. P450 6A1 reconstituted with NADPH-cytochrome P450 reductase and phosphatidylcholine did not metabolize α-pinene, limonene, or the insect growth regulators hydroprene and methoprene. The four geometric isomers of methyl farnesoate were metabolized predominantly to the 10,11-epoxides, but also to the 6,7-epoxides and to the diepoxides. The 10,11-epoxide of methyl (2E,6E)-farnesoate was produced in a 3:1 ratio of the (10S) and (10R) enantiomers. Monoepoxides of methyl farnesoate were metabolized efficiently to the diepoxides. Methyl farnesoate epoxidation was strongly inhibited by a bulky substituted imidazole. The active site topology of P450 6A1 was studied by the reaction of the enzyme with phenyldiazene to form a phenyl-iron complex. Ferricyanide-induced in situ migration of the phenyl group showed formation of the N-phenylprotoporphyrinporphyrin IX adducts in a 17:25:33:24 ratio of the N(B):N(A):N(C):N(D) isomers. These experiments suggest that metabolism of xenobiotics by this P450, constitutively overexpressed in insecticide-resistant strains of the house fly, is not severely limited by stereochemically constrained access to the active site.
