2,2-二甲基-3-羟基-6-甲氧酰基苯并吡喃的首次全合成

天然 3-羟基苯并吡喃类化合物具有重要的生物活性 ,其合成已引起了许多化学家的关注 [1] .Chen等[2 ] 报道 Kuhistanol D ( 1 )对酯多糖刺激人体外围单核细胞具有明显的抑制作用 ,但其合成研究尚未见报道 .为了探讨这类化合物的合成方法及其生物活性与结构的关系 ,我们开展其类     

苔藓植物的主要次生代谢产物与有害生物防治

苔类的主要次生代谢产物为倍半萜、联苄和二联苄,藓类则以黄酮为主。苔类植物中的抗菌、抗真菌活性成分有异戊烯基联苄、地钱素A、网地藻烷型二萜及其衍生物、酚基倍半萜、a-santonin、核子木素A、B及其衍生物、三裂鞭台醇、Dicrnenone A、DicranenoneB1等。许多苔类中富集的半月苔认为可能完全足以抵御真菌的感染。藓类中常见的双黄酮和聚酚基化合物能够抵御真菌感染和昆虫的摄食。泥炭藓醇是导致泥炭藓和灰藓类分解较慢的因素之一,苯甲酸苄酯类对昆虫和螨类是致命的,草酸对植食性昆虫有排斥作用,藓类枝条内的protocatechiuc和五倍子酸对刺激蛾科昆虫有拒食作用,其它包括绿片酮pinguisone、囊绒苔醛、桉叶油内酯、大根香叶烷、倍半萜内酯、补身基烷内酯、Gymnocolin。Albicanol aceate对金鱼有明显的拒食作用,一系列天然的补身烷及相关的合成化合物被证明对蚜虫有拒食作用。Polygodial被认为是作为昆虫拒食剂最有效的天然产物之一,还能够抑制鱼类的摄食。浮苔素A、浮苔素B、半月苔酸、半月苔甲酯、和5－羟基半月苔酸有灭螺活性。绝大多数苔藓的粗提物,特别是含有芳香性化合物的,表现出抑制发芽、根伸长、及胚芽鞘的生长的活性。半月苔酸、isobidyclogermacrenal、指叶苔醛、指叶苔醇及其羟基衍生物、硬指叶苔醇、一些2,3－断香橙烷型倍半萜半缩醛、甲氧基plagiochilines、（一）－polygodial、折瓣苔烷型二萜化合物、和3a,4a-epoxy-5a-acetoxy-18-hydroxysphenolobal13E,16E－diene对植物生长有抑制作用。     

昆虫化学生态学与植物保护

在生态安全条件下进行植物保护，推行植物免害工程是实现可持续发展的有效途径之一。笔综述了昆虫化学生态学中昆虫与植物之间、昆虫与天敌间的化学联系，信息素与植物挥发性物质在昆虫对寄主植物定位、定居、取食和繁殖中的作用，非寄主植物对植食性昆虫寄主选择的影响等领域的研究进展，以及利用植物次生性化合物进行害虫治理的应用现状。展示了昆虫化学生态学在未来植物保护中的应用前景及昆虫化学生态学的研究方向。     

亚磷酸盐微孔化合物研究进展

由于微孔材料独特的结构特点及在分离、吸附、离子交换和催化等方面的应用,探索合成具有新颖结构的微孔化合物成为当今研究的热点。磷酸盐分子筛是应用和研究最为广泛的一类微孔材料。亚磷酸盐微孔化合物作为磷酸盐分子筛材料的延伸,近年来引起科学家的极大兴趣。人们致力于合成具有大孔、螺旋、手性骨架等新颖结构的亚磷酸盐系列化合物,在很大程度上推动了微孔化合物的研究。目前,亚磷酸盐微孔化合物的研究已经涉及到元素周期表中的大部分金属元素,合成方法多样,所用模板剂种类繁多。通过对不同金属亚磷酸盐的综述,总结了亚磷酸盐化合物的结构特点、合成方法及模板剂在化合物合成中所起的作用,并介绍了其最新研究进展。     

新型2,5-二取代-1,3,4-噻二唑类化合物的合成及性能研究

1,3,4-噻二唑类杂环化合物不仅具有优良的杀虫,除草,抗植物病毒,杀菌、抗菌等生物活性,而且具有选择性好,活性高,毒性低,环境相容性好等优点,在医药和农药的研究和开发中发挥着重要作用.本文通过噻二唑重氮化后经过偶合反应合成了系列新型化合物,并用~1HNMR、IR和元素分析对目标化合物进行了结构表征,研究了它们与过渡金属离子的显色配位反应,为其在医药方面的应用提供实验基础.     

研制绿色杀虫剂的理论基础与研究现状：兼论植物对昆虫的？…

在长期的进化过程中,植物演化出了３种防御昆虫侵害的化学防御方式：（１）引起昆虫忌避和抑制其取食;（２）影响昆虫对食物的消化和利用;（３）使昆虫中毒或死亡或延迟其生长发育。植物含有的多种多样的化合物可以通过影响昆虫的神经系统、呼吸系统、肌肉系统、消化系统、生殖系统与生长发育而达到杀灭害虫、保护自己的目的,这是研制高效低毒新型杀虫剂－绿色杀虫剂的理论基础,近年来对绿色杀虫剂的研制与开发越来越深入,并且     

植物用抗病毒剂的研制

采用相转移催化剂对植物用抗病毒剂ＤＨＴ进行结构修饰，修后的化合物具有高效的抗病毒能力，选择性的除莠作用。同时还能有效地调节植物生长，是具有多方面功效新型植物物用抗病毒剂。     

含1,2,3-噻二唑杂环的双酰肼衍生物的合成与杀虫活性

双酰肼化合物作为一类重要的昆虫生长调节剂广泛用于植物保护中.为了发现新型高效低毒性的双酰肼杀虫剂先导化合物,通过在双酰肼化合物分子骨架中引入1,2,3-噻二唑杂环,设计合成了一类含1,2,3-噻二唑的双酰肼衍生物3,其结构经IR、1H NMR、ESI-MS和元素分析测试技术确证;生物活性测定结果表明,部分目标化合物在2...     

N-[(N''-取代嘧啶-2-基)-乙酰脲基]邻磺酰苯甲酰亚胺衍生物的合成与生物活性测定

运用“亚结构连接法”设计合成了 1 0种具有新型分子结构的标题化合物 ,它们的结构经IR,1 H NMR和元素分析测试而确定 .初步生物活性测试结果表明 ,大部分目标化合物具有较好的除草活性 ,主要抑制双子叶植物 (如油菜 )的生长 ,而对单子叶植物 (如水稻 )的生长无明显影响 ,具有较好的选择性 .     

盐沼入侵植物互花米草治理后植食性昆虫食物结构的变化

利用生态工程措施治理滨海盐沼入侵植物、恢复受损湿地的生态功能,是海岸带自然资源管理和生态系统健康维持的重要手段.盐沼入侵植物治理后,植食性昆虫群落结构的变化已得到较多研究,但昆虫食物结构变化的关注相对较少.本研究选取崇明东滩互花米草(Spartina alterniflora)治理工程恢复区,以及毗邻的互花米草入侵区和原生芦苇(Phragmites australis)对照区的不同植物群落,结合碳稳定同位素分析手段,比较了植物群落间植食性昆虫的食物结构差异,发现对照区、入侵区和恢复区芦苇群落中的昆虫均主要以芦苇为食,入侵区互花米草群落中的大多数昆虫以互花米草为食,而芦苇-互花米草混生群落中的昆虫既取食芦苇也取食互花米草.这一结果表明,互花米草入侵改变了本地植食性昆虫对土著植物芦苇的依赖性,而清除互花米草并恢复芦苇群落后,植食性昆虫对土著植物的依赖性已得到恢复.     

Construction of ice nucleation active <Emphasis Type="Italic">Enterobacter cloacae</Emphasis> for control of insect pests

Ice nucleation active(INA)bacteria are the most potent heterogeneous ice nuclei in nature,which have become an important biological resource for diverse applications.Many researches have proved that INA bacteria can raise the supercooling points(SCPs)of insect pests,then reduce their cold hardiness.However,INA bacteria‘s inefficient colonization on the surface or in the guts of insects,and the high incidence of frost injury induced by their release hampered the application of INA bacteria in controlling insect pests in agricultural fields.In this study,we constructed a recombinant plasmid mob-Tn5-iceA with the ability of broad-host-range conjugal mobilization and integration of the ina gene of icaA into chromosomal DNA of many gram-negative bacteria by Tn5 transposition.In addition,Ent.cloacae strains stably carrying iceA and expressing high ice nucleation activity(INA),even in the absence of antibiotic pressure,were constructed through conjugal mobilization and Tn5 transposition.Ent,cloacae strains have benn reported to be able to efficently colonize in the guts of insects,but have weak plant epiphytic ability.Therefore,these transgenic Ent.Cloacae may be promising candidates for control of insect pests in agricultural fields.     

植食性昆虫、植物和共生微生物的功能关联

植食性昆虫和植物均能与微生物形成密切关系，它们各自的生态功能及相互关系也常被共生微生物所影响。近年来，随着分子水平研究方法的进展，植食性昆虫和植物中很多可遗传共生微生物（细菌、真菌等）被发现。共生微生物能够在营养、生殖、防御和解毒等方面给宿主带来显著影响，并与宿主形成竞争、互利或寄生等关系。植食性昆虫体内的含菌胞、肠道、血淋巴、唾液腺等常含有重要功能的共生微生物。新的分子生物学手段和高通量测序技术的应用使得我们能够增加对宿主和共生微生物（即使处于低丰度）之间关系的了解。本文尝试总结了植食性昆虫和植物共生微生物的多样性及其关系、昆虫和植物互作机制、昆虫共生菌解毒植物毒素等方面的近期证据，突出强调了应以系统观思维来理解共生微生物、植食性昆虫和植物间的功能关联，并就将来值得研究的问题提出了建议。     

Lignans in man and in animal species

In our laboratories, for several years, two phenolic compounds have been detected during gas chromatographic-mass spectrometric analysis of urinary steroid extracts from human and animal species. Although features of the mass spectra of their trimethylsilyl (TMS) ether derivatives resembled those of oestrogens, they were atypical of steroids. The possibility that they were artefacts of the isolation procedures was discounted after careful studies with blanks, by varying the extraction method and because they were present almost exclusively as conjugates of glucuronic acid. Several of the general characteristics of the unknown compounds were reported after one (referred to as compound 180/442) was found to have a cyclic pattern of excretion during the menstrual cycle of an adult vervet monkey (Fig. 1). An investigation of the nature and distribution of the compounds has shown them to be urinary constituents in humans, baboons, vervet monkeys and rats, and further related compounds have been detected, so far only in vervet monkey urine. We now report spectroscopic and chemical studies that show the two original compounds to be lignans, which have a 2,3-dibenzylbutane skeleton as their basic structure. Unlike all previously known natural lignans, invariably of plant origin, the two mammalian compounds carry phenolic hydroxy groups only in the meta position of the aromatic rings.     

抗家畜体外寄生虫药新型卤硝酚类化合物的合成与表征

１ 个卤硝酚类化合物和 ５ 个含卤硝酚结构的 Ｓｃｈｉｆｆ 碱类化合物的合成方法,经元素分析,产物的 Ｃ、 Ｎ、 Ｈ 均与理论值相符．产物经红外光谱、核磁共振氢谱测定,确定了其结构,并通过 ｐ Ｋａ 的测定,推测其可能具有的驱杀动物体外寄生虫的活性     

不同类型退化山地生态系统典型区域昆虫多样性分析

2006年9—10月对云南干热河谷区三种不同的恢复生态系统进行了昆虫群落的调查,得出:研究区内植物群落的组成结构不同,显著影响昆虫群落种类的组成和结构,植物群落组成和结构越复杂,昆虫群落组成越丰富。     

Trophic cascades across ecosystems

Predation can be intense, creating strong direct and indirect effects throughout food webs. In addition, ecologists increasingly recognize that fluxes of organisms across ecosystem boundaries can have major consequences for community dynamics. Species with complex life histories often shift habitats during their life cycles and provide potent conduits coupling ecosystems. Thus, local interactions that affect predator abundance in one ecosystem (for example a larval habitat) may have reverberating effects in another (for example an adult habitat). Here we show that fish indirectly facilitate terrestrial plant reproduction through cascading trophic interactions across ecosystem boundaries. Fish reduce larval dragonfly abundances in ponds, leading to fewer adult dragonflies nearby. Adult dragonflies consume insect pollinators and alter their foraging behaviour. As a result, plants near ponds with fish receive more pollinator visits and are less pollen limited than plants near fish-free ponds. Our results confirm that strong species interactions can reverberate across ecosystems, and emphasize the importance of landscape-level processes in driving local species interactions.     

Antimicrobial peptides of multicellular organisms.

Multicellular organisms live, by and large, harmoniously with microbes. The cornea of the eye of an animal is almost always free of signs of infection. The insect flourishes without lymphocytes or antibodies. A plant seed germinates successfully in the midst of soil microbes. How is this accomplished? Both animals and plants possess potent, broad-spectrum antimicrobial peptides, which they use to fend off a wide range of microbes, including bacteria, fungi, viruses and protozoa. What sorts of molecules are they? How are they employed by animals in their defence? As our need for new antibiotics becomes more pressing, could we design anti-infective drugs based on the design principles these molecules teach us?     

瑞香亭与狼毒色原酮对昆虫的拒食和胃毒作用

采用叶碟法和夹碟法两种方法,分别就瑞香亭（daphnoritin）和狼毒色原酮（chamechromone）两种化合物对菜粉蝶（Pieris rapae L）5龄幼虫的拒食作用和胃毒作用进行了测定。结果表明：瑞香亭与狼毒色原酮两者都有较强的拒食用作用和胃毒作用。瑞香亭的拒食作用和胃毒作用比狼毒色原酮强,并随着时间的增加,两种化合物的拒食用作用和胃毒作用增强。     

Immobilized ZnO based nanostructures and their environmental applications

In the research of semiconductor metal oxides, zinc oxide (ZnO) nanomaterials have been committed to design and exploration because of their unique physical and chemical properties. ZnO has many structural characteristics and has considerable practical applications in the field of environmental technology. However, ZnO nanomaterials used for environmental functions are often presented in the form of powders. After use, they need to go through recovery processes such as centrifugation and filtration, which is also easy to cause secondary pollution. The above problems can be avoided by fixing ZnO nanostructures on substrates to form easily movable materials. Here, we present a review of our work and some others on the different synthetic strategies, formation mechanism, modification, performance and diversifications of immobilized ZnO based nanostructures, and highlight their photocatalytic related activities for environmental remediation. Various immobilized ZnO based nanostructures including nanorod arrays, 3D nanostructures, and composite heterostructures have been focused. We hope it may serve as a useful reference for researchers interested in immobilized semiconductor nanostructures and their photocatalysis and other environmental applications.     

Symbiotic fungal endophytes control insect host-parasite interaction webs

Symbiotic microorganisms that live intimately associated with terrestrial plants affect both the quantity and quality of resources, and thus the energy supply to consumer populations at higher levels in the food chain. Empirical evidence on resource limitation of food webs points to primary productivity as a major determinant of consumer abundance and trophic structure. Prey quality plays a critical role in community regulation. Plants infected by endophytic fungi are known to be chemically protected against herbivore consumption. However, the influence of this microbe-plant association on multi-trophic interactions remains largely unexplored. Here we present the effects of fungal endophytes on insect food webs that reflect limited energy transfer to consumers as a result of low plant quality, rather than low productivity. Herbivore-parasite webs on endophyte-free grasses show enhanced insect abundance at alternate trophic levels, higher rates of parasitism, and increased dominance by a few trophic links. These results mirror predicted effects of increased productivity on food-web dynamics. Thus 'hidden' microbial symbionts can have community-wide impacts on the pattern and strength of resource-consumer interactions.