应用昆虫保幼激素类似物为什么能增产蚕丝?

蚕是一种完全变态昆虫。它的一生经过卵(蚕种)、幼虫(蚕儿)、蛹和成虫(蚕蛾)等四个发育阶段,完成一个世代。蚕在一生中要经多次蜕皮和变态。它的生长、发育和变态是由蚕体内分泌的蜕皮激素和保幼激素协调控制的,而这两种激素的分泌又受脑激素的调节。在蚕的幼虫阶段,保幼激素的主要作用是保持蚕儿的幼龄体征,抑制变态。蜕皮激素与此相反,它促进蚕儿蜕皮和变态。一至四龄的蚕儿,在各龄的前期和中期,保幼激素分泌旺盛,蚕体发育成长,但到各龄后期,由于脑激素的作用,保幼激素的分泌减弱,蜕皮激素的分泌增强,致使蚕儿停食就眠,蜕皮更新。蚕儿蜕皮后,由于蚕体内还有适量的保幼激素存在,便继续起作用,进入下一个龄期发育成长。待至五龄末期,保幼激素的分泌量逐渐减少乃至完全停止,在蜕皮激素的单独作     

昆虫保幼激素类似物——734-Ⅱ号的合成

在毛主席革命路线指引下,我国一些地区开展了合成和应用昆虫保幼激素类似物的研究。在国外对保幼激素类似物的合成研究近几年很活跃,出现了活性比天然保幼激素高得多的人工合成的类似物。保幼激素的应用研究也颇活跃,七十年代初,日本科学工作者进行了保幼激素养蚕增丝的研究,得到成效。1973年,为了开辟增产桑蚕茧丝的新途径,由广     

脂肪族保幼激素类似物的合成及应用

综述了具有保幼激素活性的昆虫生长控制剂,主要是脂肪族类保幼激素类似物的合成及应用.这类保幼激素类似物的合成通常以天然易得的香茅醛或香茅醇等为原料,具有无毒、高活性、高选择性、环保及结构简单、易于合成等特点,并已被广泛地应用于多种昆虫的生长控制.     

某些保幼激素类似物的结构分析

近年来,我国的一些蚕区已推广保幼激素类似物养蚕新技术,获得良好的增产增收效果。本文报导以红外光谱,核磁共振及质谱等技术测定某些具有芳醚的保幼激素类似物的结构的实验结果。本文共讨论八种化合物(见表1)的结构测定。八种化合物共分成Ⅰ、Ⅱ、Ⅲ三组,Ⅰ组由香叶醇及酚类合成;Ⅱ组由Ⅰ组引进环氧基团而获得;而Ⅲ组则由Ⅰ组在7位引进乙氧基团而生成。     

文昌鱼卵母细胞发育成熟激素调控的研究

本文用电子显微镜技术和放射免疫测定法研究了文昌鱼卵母细胞发育成熟的激素调控。结果表明外源性GnRH-A可激发文昌鱼卵母细胞的发育成熟和产卵。用放射免疫测定法进一步揭示了GnRH-A可诱发性类固醇激素增加1—3倍,尤其17β-雌二醇的升高,与卵母细胞合成卵黄物质相一致。这些结果首次有力地证明文昌鱼卵母细胞发育成熟的激素调控与脊椎动物相类似,对文昌鱼生殖内分泌生理学有重要理论意义。     

含硫碳负离子的反应及其应用的研究——Ⅲ.合成戊烯二酸酯类的新方法

不对称取代的戊烯二酸存在于若干天然产物中。a-,β-或γ-取代的戊烯二酸及其酯类有双键互变异构和立体异构现象,其结构问题曾引起化学家们的很大兴趣.这类二酸及其酯还具有多官能团的特点,可以用于较复杂的分子的合成,例如用取代的戊烯二酸酯与适当的醛缩合,可以立体选择性地生成具有保幼激素活性的昆虫生长调节剂.     

昆虫激素和信息素化学以及昆虫的控制

在脊椎动物中有激素存在,生物学工作者已经知道一个多世纪了,化学工作者开始研究它们的化学性质也有半个多世纪了。然而昆虫激素还仅在近40年前才被发现的,对它们较多的研究则还是近10年的时间,而作为农药则更是最近几年才被研究的,现已取得了一定的效果。昆虫激素一般指的是变态激素。变态激素包括脑激素(brain hormone,BH)、保幼激素(juvenile hormone,JH)和蜕皮激素(molting hormone,MH)。昆虫的发育是经幼虫—蛹—成虫的蜕皮转变,即所谓完全变态,若不经蛹的阶段则所谓不完全变态。昆虫的胚胎后发育与成熟过程是受体内的这种激素控制的。若破坏激素系统的平衡,例如外加一定数量的激素,就会瓦解昆虫的正常生长、分化和变态的程序。在昆虫中还存在一种具有传递信     

HPLC测定葡萄糖酸盐的研究

首次应用ＨＰＬＣ测定发酵法制葡萄糖酸盐产品的质量，研究了不同色谱体系、流动相酸度对葡萄糖酸盐分离的影响；测定了多种葡萄糖酸盐（钠盐、钾盐、锌盐、锰盐、镁盐）并在所测样品中成功地分离出多个有机杂质；应用二极管阵列检测器（ＰＡＤ）对样品中杂质的来源和结构进行了初步研究；讨论了葡萄糖酸盐的现行化学测定法与液相色谱测定法之间的差异。本法简便、快速、准确     

昆虫生长调节剂3，7，11－三甲基－2，4－十二碳二烯酸乙酯及其衍生物的合成

昆虫生长调节剂３，７，１１－三甲基－２，４－十二碳二烯酸乙酯及其衍生物的合成刘天麟，谢文权，毕富春，李正名（南开大学元素有机化学研究所，天津３０００７１）３，７，１１－三甲墓－２Ｅ，４Ｅ－十二碳二烯酸乙酯１是一种具有保幼激素作用的昆虫生长调节剂。该药...     

r－氯丙基、二乙醇氨丙基键合硅胶固定相分析甾体激素药物的高效液相色谱研究

ｒ－氯丙基、二乙醇氨丙基键合硅胶固定相分析甾体激素药物的高效液相色谱研究齐广才（延安大学化学系延安７１６０００）达世禄，张元伟，王忠华（武汉大学化学系武汉４３００７２）关键词极性键合固定相，甾体激素，高效液相色谱甾体激素及其衍生物是一类重要临床药物，...     

In silico screening of the juvabione category of juvenile hormone analogues with juvenile hormone binding protein of Galleria mellonella – a docking study

Juvabione, dehydrojuvabione and their aromatic analogues act as juvenile hormone mimics against diverse strains of insect species. Large numbers of modified juvenoids containing the juvabione skeleton, with various structural variations, are synthesized. Some of these compounds exhibit a very high degree of juvenile hormone activity and are presently in use. In this paper we report a comparative molecular docking study of synthesized juvabione, natural juvenile hormone III and synthetic insect growth regulators (fenoxycarb, S-21149, Compound 1, pyriproxyfen) with the juvenile hormone binding protein of Galleria mellonella. The study clearly indicates a higher binding affinity of nitro-substituted juvabione over natural juvenile hormone III and synthetic insect growth regulators such as fenoxycarb and S-21149.     

Boll Weevil: Determination of Ecdysteroids and Juvenile Hormones with High Pressure Liquid Chromatography

Abstract

High pressure liquid chromatographic methods were developed to separate 20-hydroxyecdysone and juvenile hormone I in the pupal and adult stages of the boll weevil. Minimum detectable levels were 4 ng for 20-hydroxyecdysone and 4 ng for juvenile hormone. No juvenile hormones were detected in male boll weevils, whereas titers were readily determined in female boll weevils. The ecdysteroid, 20-hydroxyecdysone was present in pupae (not sexed), in adult males from 3 to 6 days of age, and in adult females from days 2 through 6.     

Analysis of Insect Hormones by Means of a Radial Compression Separation System

Abstract

The use of a radial compression separation system for the analysis of insect hormones is described. By simple isocratic elution, both steroid molting hormones and terpenoid juvenile hormones are rapidly separated. The system is used to analyze the metabolism of juvenile hormone by an established cell line of Drosophila melanogaster.     

Synthèse stéréospécifique récurrente de structures apparentées à celle de l'hormone juvénile de Hyalophora cecropia

A stereospecific synthesis of Hyalophora cecropia juvenile hormone analogs is proposed. The three double bonds are obtained successively by addition of an alkyl copper reagent to the apporpriate 1-alkyne.     

Carbon-13 nuclear magnetic resonance spectra of juvenile hormone III,some of its derivatives,and of analogous compounds

The ¹³C NMR spectra of methyl farnesoate and related compounds, including juvenile hormone III, are presented, as well as those of analogous compounds derived from methyl geranate. Correlations between the homologous derivatives are discussed in terms of substituent influences.     

香茅基芳基醚类保幼激素类似物的简便合成方法

许多香叶基芳基醚和香茅基芳基醚已证明是有效的昆虫保幼激素^[1-3].以往合成此类化合物,只能在酚与较活泼的香叶基溴的反应中使用KOH(或NaOH),与较不活泼的香茅基溴的反应则仍沿用Williamson法.我们曾报导了以聚氧乙烯类表面活性剂代替冠醚作为相转移催化剂合成醚类化合物的方法^[4].     

Synthesis and biological activity of permethrin analogs containing various substituents in position <Emphasis Type="Italic">2</Emphasis> of the cyclopropane ring

A number of permethrin derivatives having various substituents (Me, Et, Pr, Ph, PhCH₂, PhCH₂CH₂) in position 2 of the cyclopropane ring were synthesized and assayed for insecticidal activity against typhoid flies, rice weevils, and black bean aphid and juvenile hormone activity against flour beetle chrysalises. The examined compounds showed a weak insecticidal activity. Some derivatives were found to exert knockdown effect analogous to that of commercial pyrethroid tetramethrin; however, unlike permethrin, they exhibited pronounced juvenile hormone activity.     

Enantio- and diastereo-controlled synthesis of (+)-juvabione employing organocatalytic desymmetrization and photoinduced fragmentation

(+)-Juvabione, a natural sesquiterpene exhibiting insect juvenile hormone activity, has been synthesized from sigma-symmetric 4-(2-formyl-ethyl)cyclohexanone by employing organocatalytic asymmetric aldolization and Norrish I-type fragmentation as the key steps.     

Optimization and validation of an enzyme immunoassay for the insect growth regulator fenoxycarb

A competitive enzyme-linked immunosorbent assay (ELISA) was developed for the quantitative detection of the insect growth regulator fenoxycarb. Polyclonal rabbit antisera, raised against protein conjugates of four haptenic derivatives of fenoxycarb, were utilized in immobilized antigen-based, competitive immunoassays. With ELISA systems that were both hapten- and carrier-heterologous, most antiserum titers fell in the range of 1:1000-1:30,000. Assay conditions, including concentrations of antisera and coating antigens, were optimized. The effect of pH, organic solvents, and various blocking agents was also investigated. A hapten-homologous and two hapten-heterologous indirect ELISAs allowed fenoxycarb determination in the range of 0.1-85 ng ml⁻¹ with apparent IC₅₀ values of 1.2-2.8 ng ml⁻¹. Cross-reactivities with a number of compounds (e.g. pesticides of related structure, hapten synthesis intermediates, fenoxycarb metabolite, photodegradation products) were determined, and the assay proved highly selective for fenoxycarb. In particular, no significant interference was found with selected pyrethroid and juvenile hormone analog insecticides, phenoxyacetic acid herbicides, and photodegradation products of fenoxycarb. Using spiked water samples, assay performance was validated by SPME/GC-MS.