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1.
Hexadecadien-1-ol and the derivatives (acetate and aldehyde) with a conjugated diene system have recently been identified from a pheromone gland extract of the persimmon fruit moth (Stathmopoda masinissa), a pest insect of persimmon fruits distributed in East Asia. The alcohol and acetate showed their base peaks at m/z 79 in a GC-MS analysis by electron impact ionization, but the aldehyde produced a unique base peak at m/z 84, suggesting a 4,6-diene structure. To confirm this inference, four geometrical isomers of each 4,6-hexadecadienyl compound were synthesized by two different routes in which one of two double bonds was furnished in a highly stereoselective manner. Separation of the two isomers synthesized together by each route was facilely accomplished by preparative HPLC. Their mass spectra coincided well with those of natural components, indicating that they were available for use as authentic standards for determining the configuration of the natural pheromone. Furthermore, other hexadecadienyl compounds, including the conjugated diene system between the 3- and 10-positions, were synthesized to accumulate the spectral data of pheromone candidates. 5,7-Hexadecadienal interestingly showed the base peak at m/z 80; meanwhile, the base peaks of its alcohol and acetate were detected at m/z 79 like the corresponding 4,6-dienes. The base peaks of all 6,8-, 7,9-, and 8,10-dienes universally appeared at m/z 67 like 9,11-, 10,12-, and 13,15-dienes, the spectra of which have already been published. Although 3,5-hexadecadienal was not prepared, base peaks at m/z 67 and 79 were recorded for the alcohol and acetate, respectively.  相似文献   

2.
一种用于昆虫性信息素成分单不饱和双键定位的简便方法   总被引:1,自引:0,他引:1  
昆虫利用特定的性信息素成分实现种内信息交流和种间生殖隔离,性信息素成分异构体的细微差异都能导致其生物活性的很大改变。本研究利用二甲基二硫醚(DMDS)甲硫基化反应和气相色谱-电子轰击质谱(GC-EI-MS)的方法对脂肪族单不饱和醇、醛和乙酸酯类昆虫性信息素成分双键在碳链中的位置异构进行系统研究。质谱分析结果表明,含有醇和乙酸酯官能团的单不饱和烯烃甲硫基化衍生物的质谱特征碎片分子离子峰(M+)及2个主要的诊断离子m/z 61+14m [H-(CH2m-CH=S+ CH3]和77+14n[CH3S+ =CH(CH2nOH](或119+14n,[CH3S+ =CH(CH2nOOCCH3])丰度都很强,可以据此直接推断双键在碳链中的位置。尽管单不饱和醛类化合物DMDS衍生物的特征碎片峰也很明显,但是由于羰基的质量数和2个亚甲基的质量数相同,不能由低分辨质谱的特征碎片峰直接推断双键在碳链中的位置。DMDS甲硫基化反应结合GC-EI-MS分析方法鉴定昆虫性信息素成分单不饱和双键在碳链中的位置异构,该方法简单快捷,为昆虫性信息素的结构鉴定工作奠定了坚实的基础。  相似文献   

3.
The correlation between triacylglycerols containing conjugated diene fatty acyl moieties and pheromone aldehydes in the sex pheromone glands of females of Manduca sexta was investigated. Females decapitated 15 h after adult emergence neither called nor produced pheromone during the natural period of pheromone production on the subsequent two nights. However, these females could be stimulated to produce sex pheromone for prolonged periods by repeated injection of synthetic pheromone biosynthesis activating neuropeptide (PBAN). Gas chromatographic analysis of methanolysis products of lipids extracted from the pheromone glands of decapitated and intact females showed no differences in the amounts of fatty acyl precursors of pheromone. High performance liquid chromatographic analysis of the triacylglycerols containing conjugated diene analogues of the pheromone components (diene TG), obtained 24 and 48 h after decapitation, showed that the total amounts of these components were not affected by decapitation. The amounts of all diene TG peaks declined significantly when decapitated females were stimulated to produce pheromone during a 7 h period by repeated injection of PBAN at 3 h intervals but recovered when pheromone production subsided. These results indicate that PBAN induces liberation of pheromone precursors from the triacylglycerols during pheromone biosynthesis but does not induce replenishment of this storage pool. © 1996 Wiley-Liss, Inc.
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America
  •   相似文献   

    4.
    The female sex pheromones of the Mediterranean processionary moths (Thaumetopoea sp.) are conjugated dienes or enynes of 16 carbon atoms with the unsaturations located at C11 and C13. To investigate the biochemical basis of this phenotypic variation, the biosynthetic pathway of T. processionea sex pheromone, a diene acetate, has been elucidated and compared to that reported for the enyne-producing species T. pityocampa. Mass labeling experiments showed that T. processionea sex pheromone is biosynthesized from palmitic acid, by subsequent (Z)-11 and (Z)-13 desaturations and final reduction and acetylation. The Pheromone Biosynthesis Activating Neuropeptide (PBAN) activates this biosynthetic pathway downstream of the dienoate intermediate. When either 11-hexadecynoic acid or (Z)-13-hexadecen-11-ynoic acid were administered to T. processionea, this species was able to produce the enyne sex pheromone of T. pityocampa upon PBAN stimulation. In contrast, T. pityocampa does not produce either 11-hexadecynyl acetate or (Z,Z)-11,13-hexadecadienyl acetate, despite having the corresponding precursors in the pheromone gland. However, both acetates are detected after administration of the corresponding alcohols. These overall results suggest that the absence of delta(11) acetylenase and the existence of an enynoate specific reductase in the diene and enyne-producing Thaumetopeae, respectively, account for the different sex pheromones produced by the two groups.  相似文献   

    5.
    马尾松毛虫性信息素在不同类型诱芯中的稳定性   总被引:7,自引:0,他引:7  
    高伟  赵成华  施再喜 《昆虫学报》2001,44(2):213-220
    顺5,反7-十二碳二烯醇、顺5,反7-十二碳二烯乙酸酯和顺5,反7-十二碳二烯丙酸酯是马尾松毛虫Dendrolimus punctatus性信息素的主要成分。为研究如何减少上述共轭二烯信息素成分中的几何构型异构化和氧化的发生,作者制备了几种不同剂型的诱芯并进行了田间诱蛾试验。与常用的天然橡胶诱芯相比,诱芯中加入抗氧化剂(topanol CA)、提高性信息素的纯度、每5天重新更换诱芯及将载体换为硅橡胶等处理均不能明显提高诱芯的诱蛾效果,然而载体为复合橡胶(氯化丁基橡胶和天然橡胶的混合体)的诱芯诱蛾效率比天然橡胶诱芯提高了1倍以上。田间试验后,用毛细柱气相色谱对不同类型诱芯中残留的信息素及其异构体的分析结果显示:复合橡胶诱芯中只有12%~16%的不同信息素成分发生了异构化,而在天然橡胶诱芯中此值高达69%~87%。而且前者中信息素及其异构体的剩余量是后者的4倍。这些结果表明,复合橡胶诱芯之所以具有较高的诱效,主要由于在这种诱芯中,共轭二烯信息素更稳定,释放速率较为缓慢且均匀。  相似文献   

    6.
    Females of the sibling silkmoth species Antheraea polyphemus and A. pernyi use the same three sex pheromone components in different ratios to attract conspecific males. Accordingly, the sensory hairs on the antennae of males contain three receptor cells sensitive to each of the pheromone components. In agreement with the number of pheromones used, three different pheromone-binding proteins (PBPs) could be identified in pheromone-sensitive hairs of both species by combining biochemical and molecular cloning techniques. MALDI-TOF MS of sensillum lymph droplets from pheromone-sensitive sensilla trichodea of male A. polyphemus revealed the presence of three major peaks with m/z of 15702, 15752 and 15780 and two minor peaks of m/z 15963 and 15983. In Western blots with four antisera raised against different silkmoth odorant-binding proteins, immunoreactivity was found only with an anti-(Apol PBP) serum. Free-flow IEF, ion-exchange chromatography and Western blot analyses revealed at least three anti-(Apol PBP) immunoreactive proteins with pI values between 4.4 and 4.7. N-Terminal sequencing of these three proteins revealed two proteins (Apol PBP1a and Apol PBP1b) identical in the first 49 amino acids to the already known PBP (Apol PBP1) [Raming, K. , Krieger, J. & Breer, H. (1989) FEBS Lett. 256, 2215-2218] and a new PBP having only 57% identity with this amino-acid region. Screening of antennal cDNA libraries with an oligonucleotide probe corresponding to the N-terminal end of the new A. polyphemus PBP, led to the discovery of full length clones encoding this protein in A. polyphemus (Apol PBP3) and in A. pernyi (Aper PBP3). By screening the antennal cDNA library of A. polyphemus with a digoxigenin-labelled A. pernyi PBP2 cDNA [Krieger, J., Raming, K. & Breer, H. (1991) Biochim. Biophys. Acta 1088, 277-284] a homologous PBP (Apol PBP2) was cloned. Binding studies with the two main pheromone components of A. polyphemus and A. pernyi, the (E,Z)-6, 11-hexadecadienyl acetate (AC1) and the (E,Z)-6,11-hexadecadienal (ALD), revealed that in A. polyphemus both Apol PBP1a and the new Apol PBP3 bound the 3H-labelled acetate, whereas no binding of the 3H-labelled aldehyde was found. In A. pernyi two PBPs from sensory hair homogenates showed binding affinity for the AC1 (Aper PBP1) and the ALD (Aper PBP2), respectively.  相似文献   

    7.
    P Xu  AM Hooper  JA Pickett  WS Leal 《PloS one》2012,7(9):e44190
    The insect olfactory system, particularly the peripheral sensory system for sex pheromone reception in male moths, is highly selective, but specificity determinants at the receptor level are hitherto unknown. Using the Xenopus oocyte recording system, we conducted a thorough structure-activity relationship study with the sex pheromone receptor of the silkworm moth, Bombyx mori, BmorOR1. When co-expressed with the obligatory odorant receptor co-receptor (BmorOrco), BmorOR1 responded in a dose-dependent fashion to both bombykol and its related aldehyde, bombykal, but the threshold of the latter was about one order of magnitude higher. Solubilizing these ligands with a pheromone-binding protein (BmorPBP1) did not enhance selectivity. By contrast, both ligands were trapped by BmorPBP1 leading to dramatically reduced responses. The silkworm moth pheromone receptor was highly selective towards the stereochemistry of the conjugated diene, with robust response to the natural (10E,12Z)-isomer and very little or no response to the other three isomers. Shifting the conjugated diene towards the functional group or elongating the carbon chain rendered these molecules completely inactive. In contrast, an analogue shortened by two omega carbons elicited the same or slightly higher responses than bombykol. Flexibility of the saturated C1-C9 moiety is important for function as addition of a double or triple bond in position 4 led to reduced responses. The ligand is hypothesized to be accommodated by a large hydrophobic cavity within the helical bundle of transmembrane domains.  相似文献   

    8.
    昆虫性信息素多数为长链的不饱和醇、醋酸酯、醛或酮类,链长一般为10-20碳,主要在性信息素腺体内由乙酰辅酶A经过脂肪酸合成、碳链缩短、去饱和以及碳酰基的还原修饰等步骤合成的;而性信息素合成激活肽(pheromone biosynthesis activating neuropeptide,PBAN)是由昆虫食管下神经节中的部分神经细胞合成和分泌的神经肽,通常由33个氨基酸组成,在C-末端有一个相同的五肽序列,主要调控性信息素的生物合成。有关PBAN的细胞内信号转导是近几年的研究热点,研究显示 PBAN首先与性信息素腺体细胞表面的G蛋白偶联受体结合,随后依据昆虫种类的不同,其细胞内信号转导方式主要有三种:(1)以cAMP信号传导途径进行信号转导;(2)以cAMP和磷脂酰肌醇信号传导途径共同进行信号转导;(3)主要以Ca2 为第二信使进行信号传导。  相似文献   

    9.
    The Japanese persimmon treeborer, Synanthedon tenuis (Butler) (Lepidoptera: Sesiidae), is a harmful pest of persimmon trees (Diospyros spp.). Because males of this species are known to be attracted by (3Z,13Z)-3,13-octadecadienyl acetate (Z3,Z13-18:OAc), a mating disruptant composed of a 1:1 mixture of Z3,Z13-18:OAc and the (3E,13Z)-isomer, the original target of which is an allied pest, S. hector (Butler), has been diverted to control S. tenuis. However, the sex pheromone secreted by S. tenuis females has not been characterized. Analyses of pheromone gland extracts using gas chromatography (GC) equipped with an electroantennographic detector (GC-EAD) and GC combined with mass spectrometry (GC–MS) detected only Z3,Z13-18:OAc, and no other known sesiid pheromone components were found. In a persimmon orchard, S. tenuis males were selectively attracted by a lure baited with Z3,Z13-18:OAc among four geometrical isomers of 3,13-octadecadienyl acetate, indicating that males strictly discriminated among the configurations of the two double bonds. Lures baited with single Z3,Z13-18:OAc attracted only S. tenuis. Further field experiments revealed that the attractiveness of Z3,Z13-18:OAc is significantly inhibited by the addition of the (3E,13Z) isomer or the parent alcohol.  相似文献   

    10.
    Female pheromone glands of the leafroller Argyrotaenia sphaleropa were analyzed. Two acetates were identified as (11Z,13)-tetradecadien-1-yl acetate and (11Z)-tetradecen-1-yl acetate by comparison with synthesized references. The (11Z,13)-tetradecadien-1-yl acetate and the aldehyde (11Z,13)-tetradecadienal were synthesized via a Wittig reaction. A field-trapping test showed that a lure consisting of a mixture of (11Z,13)-tetradecadienal and (11Z,13)-tetradecadien-1-yl acetate in a 10:1-ratio produced the highest trap catches.  相似文献   

    11.
    Analysis by TLC and HPLC revealed that the triacylglycerols comprise the most abundant lipid class in the sex pheromone glands of Manduca sexta females. Also, conjugated olefinic acyl analogs of the major pheromone aldehydes occur principally in the triacylglycerols. The amount of triacylglycerols with conjugated diene acyl moieties significantly decreased when the period of pheromone production was extended by 7 h beyond the normal period of pheromone production by 3 injections of pheromone biosynthesis activating neuropeptide (PBAN) at 3 h intervals. This decrease indicates that the triacylglycerols stored in the gland may serve as major sources of pheromone precursors in the biosynthesis of the sex pheromone aldehydes. Furthermore, analysis of pheromone aldehydes and triacylglycerols in the gland from moths treated with PBAN showed that the proportions of the triacylglycerols with conjugated diene moieties were closely correlated with the proportions of aldehydes found in the same gland. This correlation suggests that the proportions of fatty acids bound to certain triacylglycerols regulates the proportions of aldehydes in biosynthesis of the pheromone blend in M. sexta. © 1995 Wiley-Liss, Inc.
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America.
  •   相似文献   

    12.
    《Journal of Asia》2020,23(2):306-309
    Timely insecticidal application for Stathmopoda masinissa Meyrick (Lepidoptera: Stathmopodidae), is important, for reducing damage to persimmon (Diospyros kaki Thunb.), an important tree fruit cultivated in Korea. In this regard, the early and precise detection of adult S. masinissa is desirable. In this study, we report the effect of (E4,Z6)-4,6-hexadecadienal (E4,Z6-16Ald) with sex pheromone components in attracting S. masinissa males. The sex pheromone of S. masinissa in the Korean population comprised two components, (E4,Z6)-4,6-hexadecadienyl acetate (E4,Z6-16Ac) and (E4,Z6)-4,6-hexadecadienol (E4,Z6-16OH). It was shown that the E4,Z6-16Ald acts as a synergist of E4,Z6-16Ac for attracting S. masinissa in the Japanese population. To test whether E4,Z6-16Ald could be used as an attractant in the Korean population, the E4,Z6-16Ald with the two pheromone components was evaluated in attracting S. masinissa males. Electroantennography (EAG) assays were performed to determine the antennal responses of S. masinissa males to the two pheromone components and E4,Z6-16Ald tested. A field attraction test with a combination of pheromones and E4,Z6-16Ald was carried out for 3 years in three different regions in Korea. E4,Z6-16Ald elicited as high a response as the two pheromone components. A mixture of the two pheromone components and E4,Z6-16Ald and a mixture of E4,Z6-16Ac and E4,Z6-16Ald attracted more S. masinissa males than a mixture of E4,Z6-16Ac and E4,Z6-16OH, the pheromone of Korean population. This new pheromone lure formulation with E4,Z6-16Ald is expected to contribute to the precise detection of S. masinissa by luring males to pheromone-baited traps.  相似文献   

    13.
    The ability of pheromone receptor cells of male Antheraea polyphemus (Saturniidae) to resolve stimulus pulses was determined at different temperatures (8°, 18°, 28°C). The cells were stimulated by repeated 20-ms puffs of the pheromone components (E, Z)-6, 11-hexadecadienyl acetate and (E, Z)-6,11-hexadecadienal. At higher temperatures, higher frequencies of stimulus pulses were resolved by the nerve-impulse response: about 1.25 pulses per second at 8°C, 2.5 pulses/s at 18°C and 5 pulses/s at 28°C. The decreased ability of receptor cells to resolve stimulus pulses at low temperatures may reduce the male moth's chance of reaching the pheromone source. The peak nerve-impulse frequency increased whereas the duration of nerve-impulse responses to single stimulus pulses decreased at higher temperatures. At a given temperature and stimulus intensity the peak nerveimpulse frequency decreased with shorter intervals between the stimulus pulses, but the duration of the responses remained almost constant. The time needed for recovery from adaptation caused by a single stimulus pulse was longer at lower temperatures. The aldehyde receptor cell recovered more quickly than the acetate cell. At low stimulus concentration, the resolution ability of the acetate cell was strongly decreased, whereas in the aldehyde cell it was only slightly impaired.  相似文献   

    14.
    A series of [4,6-(substituted aryl)-2-thioxo-1,2,3,4-tetrahydro-pyrimidin-5-yl]-acetic acid (4a-r) has been synthesized by the base catalyzed condensation of beta-aroylpropionic acid, thiourea with aldehyde in ethanol. Structures of the new compound were established on the basis of (1)H NMR and IR spectral data. Anti-inflammatory activity in vivo were evaluated and compared with standard drug diclofenac sodium. Some compounds have shown moderate activity.  相似文献   

    15.
    A new oligomeric derivative was synthesized from prostaglandin B2 and ascorbic acid, and its effect on rat brain ischemia-reperfusion injury was studied. Brain ischemia was produced in the rat by the combination of bilateral common carotid artery occlusion and hemorrhagic hypotension (30 mmHg, 20 min). The cerebral cortex was homogenized in the presence of the spin trap agent, N-tert-butyl-alpha-phenyl-nitrone (PBN). Spin-adducts were detected using an electron spin resonance spectrometer (EPR). Lipid peroxidation was estimated from the amounts of both thiobarbituric acid reactive substances (TBAR) and conjugated diene. In control experiments, reperfusion induced a burst of free radical formation which peaked at 5 min reperfusion time (238 +/- 41%). Lipid peroxidation increased significantly after 20 min of reperfusion (TBAR, 161 +/- 50%; conjugated diene, 160 +/- 29%). When the oligomeric derivative was administered (9 mg/kg i.p. 30 min before ischemic insult), it significantly reduced both spin adduct formation (103 +/- 13%) and lipid peroxidation (TBAR, 109 +/- 14%; conjugated diene, 97 +/- 33%).  相似文献   

    16.
    The fall webworm, Hyphantria cunea Drury (Lepidoptera: Arctiidae), is a harmful polyphagous defoliator. Female moths produce the following four pheromone components in a ratio of about 5:4:10:2; (9Z,12Z)-9,12-octadecadienal (I), (9Z,12Z,15Z)-9,12,15-octadecatrienal (II), cis-9,10-epoxy-(3Z,6Z)-3,6-henicosadiene (III), and cis-9,10-epoxy-(3Z,6Z)-1,3,6-henicosatriene (IV). Although 13C-labeled linolenic acid was not converted into trienal II at the pheromone glands of H. cunea females, GC-MS analysis of an extract of the pheromone gland treated topically with 13C-labeled linolenyl alcohol showed the aldehyde incorporating the isotope. Other C18 and C19 fatty alcohols were also oxidized to the corresponding aldehydes in the pheromone gland, indicating a biosynthetic pathway of IIvia linolenyl alcohol and low substrate selectivity of the alcohol oxidase in the pheromone gland. On the other hand, epoxydiene III was expected to be produced by specific 9,10-epoxidation of the corresponding C21 trienyl hydrocarbon, which might be biosynthesized from dietary linolenic acid in oenocytes and transported to the pheromone gland. The final biosynthetic step in the pheromone gland was confirmed by an experiment using deuterated C21 triene, which was synthesized by the chain elongation of linolenic acid and LiAlD4 reduction as key reactions. When the labeled triene was administered to the female by topical application at the pheromone gland or injection into the abdomen, deuterated III was detected in a pheromone extract by GC-MS analysis. Furthermore, the substrate selectivity of epoxidase and selective incorporation by the pheromone glands were examined by treatments with mixtures of the deuterated precursor and other hydrocarbons such as C19-C23 trienyl, C21 dienyl, and C21 monoenyl hydrocarbons. The 9,10-epoxy derivative of each alkene was produced, while the epoxidation of the C21 monoene was poorer than those of the trienes and diene. The low selectivity indicated that the species-specific pheromone of the H. cunea female was mainly due to the critical formation of the precursor of each component.  相似文献   

    17.
    A highly accurate method has been developed for detection and quantitation of 3 alpha-hydroxy-1-methylen-5 alpha-androstan-17-one, the major urinary metabolite of methenolone acetate (Primobolan) in man. Unlabelled as well as 2H-labelled 3 alpha-hydroxy-1-methylen-5 alpha-androstan-17-one were synthesized from 1-methylen-5 alpha-androstane-3,17-dione. A fixed amount of the internal standard was added to a fixed amount of urine and the mixture was treated with Helix pomatia for 24 h. After extraction and purification by t.l.c., the mixture was converted into methoxime--trimethylsilyl derivative and analyzed by combined GC--MS. Unlabelled 3 alpha-hydroxy-1-methylen-5 alpha-androstan-17-one could be quantitated from the ratio between the tracings of the ions at m/z 372 and m/z 375 (corresponding to the M-31 ions). In alternative procedures, the ions at m/z 403 and m/z 406 (molecular ions) as well as m/z 282 and m/z 285 (M-90-31 ions) could be used. Under the conditions employed, the metabolite could be identified and quantitated in concentrations exceeding 10 ng/ml. Significant amounts of the metabolite could be detected in urine during 5 days after a single oral ingestion of 10 mg of Primobolan. The method has been successfully used for analyses of urine samples obtained from athletes involved in competition.  相似文献   

    18.
    Two sugar biosynthetic cassette plasmids were used to direct the biosynthesis of a deoxyaminosugar. The pOTBP1 plasmid containing TDP-glucose synthase (desIII), TDP-glucose-4,6-dehydratase (desIV), and glycosyltransferase (desVII/desVIII) was constructed and transformed into S. venezuelae YJ003, a strain in which the entire gene cluster of desosamine biosynthesis is deleted. The expression plasmid pOTBP3 containing 4-aminotransferase (gerB) and 3,5-epimerase (orf9) was transformed again into S. venezuelae YJ003- OTBP1 to obtain S. venezuelae YJ003-OTBP3 for the production of 4-amino-4,6-dideoxy-L-glucose derivatives. The crude extracts obtained from S. venezuelae ATCC 15439, S. venezuelae YJ003, and S. venezuelae YJ003-OTBP3 were further analyzed by TLC, bioassay, HPLC, ESI/MS, LC/MS, and MS/MS. The results of our study clearly shows that S. venezuelae YJ003-OTBP3 constructs other new hybrid macrolide derivatives including 4-amino-4,6-dideoxy-L-glycosylated YC-17 (3, [M+ Na+] m/z=464.5), methymycin (4, m/z=480.5), novamethymycin (6, m/z=496.5), and pikromycin (5, m/z=536.5) from a 12- membered ring aglycon (10-deoxymethynolide, 1) and 14-membered ring aglycon (narbonolide, 2). These results suggest a successful engineering of a deoxysugar pathway to generate novel hybrid macrolide derivatives, including deoxyaminosugar.  相似文献   

    19.
    (Z)-11-Hexadecenyl acetate, the main pheromone component of Sesamia nonagrioides sex pheromone, is biosynthesized from palmitic acid by Delta(11)-desaturation followed by reduction and acetylation. Production of (Z)-11-hexadecenyl acetate is regulated by the Pheromone Biosynthesis Activating Neuropeptide (PBAN). Transformation of (Z)-11-hexadecen-1-ol into the corresponding acetate is a target step for PBAN in the regulation of this biosynthetic sequence, thus being the first example of a PBAN-activated acetylation. The production of the minor component (Z)-11-hexadecenal is also stimulated by PBAN. The usefulness of pentafluorobenzyloxime-derivatives for the analysis of aldehyde pheromone constituents by gas chromatography coupled to mass spectrometry is also reported.  相似文献   

    20.
    M Numazawa  S Yamaguchi 《Steroids》1999,64(3):187-196
    A series of 6alpha- and 6beta-phenylaliphatic-substituted androsta-1,4-diene-3,17-diones [9b-f and 10b-f; (CH2)nPh, n = 1-5] and their 4,6-diene and 1,4,6-triene analogs (11b-f and 12b-f) along with their respective phenyl analogs 9a-12a were synthesized and tested as aromatase inhibitors. All of the steroids examined were very powerful competitive inhibitors of aromatase in human placental microsomes with apparent Ki values ranging from 8.5 to 80 nM. The inhibitory activities of the benzyl- and phenethyl-4,6-dienes 11b and 11c (Ki, 9.0 and 10 nM) as well as the 6-phenethyl-1,4,6-triene 12c (Ki, 8.5 nM) were extremely high among them. All of the phenylaliphatic steroids, except for the 6beta-phenethyl compound 10c, and the 6-phenyl-4,6-diene 11a had higher affinity for aromatase than the corresponding parent 1,4-diene, 4,6-diene, and 1,4,6-triene steroids 9g, 11g, and 12g. All of the 6alpha-substituted 1,4-dienes (9a-9g) and the 6-substituted 1,4,6-trienes (12a-12g) caused a time-dependent inactivation of aromatase. On the other hand, only the 6beta-substituted 1,4-dienes (10a-10d) having no or less than four carbon atoms between the steroid nucleus and the phenyl group also caused a time-dependent inactivation of aromatase. Their inactivation rates (k(inact) 0.076-0.156 min(-1)) were higher than the respective parent steroids, 9g and 12g. In contrast, in the 4,6-diene series, only the 6-phenpropyl steroids 11d inactivated aromatase in a time-dependent manner with 0.155 min(-1) of k(inact) value. The inactivation was prevented by the substrate androstenedione, and no significant effect of L-cysteine on the inactivation was observed in each case. These results indicate that length and/or stereochemistry of the C-6 substituent of steroids 9-12 as well as a terminal phenyl group incorporated in the C-6 substituent play a critical role not only in tight binding to the active site of aromatase but also in the cause of a time-dependent inactivation of the enzyme.  相似文献   

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