皮甲甲虫从 (-) 和 (+) -α中选择性地产生cis和trans-verbenol
Science (New York, N.Y.)
|January 16, 1976
概括
伊普斯 (Ips paraconfusus) 甲虫将阿尔法-皮内因的光学异构体转化为几何异构体. 甲虫性决定了来自宿主树前体的特定聚合激素的产生.
科学领域:
- 化学生态化学生态学
- 昆虫的行为昆虫的行为
- 有机化学 有机化学
背景情况:
- 像Ips paraconfusus这样的甲甲虫依赖聚合激素来生存和繁殖.
- 这些激素的生物合成对于甲虫的交流和种群动态至关重要.
- 了解甲虫和它们的宿主树木之间的化学相互作用对于森林管理至关重要.
研究的目的:
- 通过Ips paraconfusus研究α-皮内因光学异构体的立体选择性转化为费洛蒙.
- 为了确定前体分子的性是否影响皮皮甲虫中的费洛蒙产量.
- 为了阐明在Ips paraconfusus中控制异构体转换的独特生物系统.
主要方法:
- 成年Ips paraconfusus (雄性和雌性) 暴露于 (-) - 阿尔法 - 皮和 (+) - 阿尔法 - 皮的蒸汽.
- 分析由甲虫产生的产生的费洛蒙化合物.
- 鉴定和表征烯醇的光学和几何同体.
主要成果:
- (-) -α-pinene被选择性地转化为 (+) -cis-verbenol,这是Ips paraconfusus的一个关键激素.
- (+) - - - 烯被氧化成 (+) - - 跨烯醇.
- 一个生物系统的演示,其中光学异构体被转换为几何异构体.
结论:
- 宿主树中的α-pinene前体的奇拉性可以控制树皮甲虫产生其聚合费洛蒙的能力.
- Ips paraconfusus表现出对费洛蒙合成的立体选择性代谢能力.
- 这一发现凸显了昆虫化学生态与宿主植物化学之间的复杂关系.
相关概念视频
02:37Disubstituted Cyclohexanes: cis-trans Isomerism
Depending upon the different spatial orientation of the substituents, the disubstituted cycloalkanes exhibit two types of stereoisomers. The cis isomers have the substituents on the same side of the ring, whereas the trans isomers have the substituents on the opposite sides. These stereoisomers exhibit different physical properties and cannot be interconverted without breaking the carbon-carbon bonds.
In cyclohexane, the substituents can occupy different positions generating distinct isomers.
In cyclohexane, the substituents can occupy different positions generating distinct isomers.
02:01Isomerism in Alkenes
Alkenes like 1-butene and 2-butene exhibit constitutional isomerism, as they differ in the position of the double bond. Further, 2-butene exhibits stereoisomerism and exists as two distinct compounds differing in spatial arrangement.
An isomer is called cis-2-butene when the methyl groups are on the same side of the double bond, and the other stereoisomer, in which methyl groups are on the opposite side of the double bond, is called trans-2-butene. The cis and trans stereoisomers are not...
An isomer is called cis-2-butene when the methyl groups are on the same side of the double bond, and the other stereoisomer, in which methyl groups are on the opposite side of the double bond, is called trans-2-butene. The cis and trans stereoisomers are not...
02:46Halogenation of Alkenes
Halogenation is the addition of chlorine or bromine across the double bond in an alkene to yield a vicinal dihalide. The reaction occurs in the presence of inert and non-nucleophilic solvents, such as methylene chloride, chloroform, or carbon tetrachloride.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
01:09Conjugate Addition to α,β-Unsaturated Carbonyl Compounds
α,β-Unsaturated carbonyl compounds are molecules bearing a carbonyl and alkene functionality in conjugation with each other. The conjugation in the molecule leads to three resonance structures. The hybrid form exhibits two probable electrophilic sites: the carbonyl carbon and the β carbon.
01:28Forced Transdifferentiation
Transdifferentiation, also known as lineage reprogramming, was first discovered by Selman and Kafatos in 1974 in silkmoths. They observed that the moths’ cuticle-producing cells transformed into salt-producing cells. Many such cases of natural transdifferentiation occur in organisms. In humans, pancreatic alpha cells can become beta cells. In newts, the loss of the eye’s lens causes the pigmented epithelial cells to transdifferentiate into the lens cells.
Artificial transdifferentiation occurs...
Artificial transdifferentiation occurs...
01:16Transduction
Among the three main modes of HGT—transformation, conjugation, and transduction—transduction is unique in that it is mediated by bacteriophages, or bacterial viruses.Transduction occurs in two ways. Generalized transduction occurs during the lytic cycle of a bacteriophage infection. In this process, bacteriophages infect bacterial cells, replicate within them, and ultimately cause cell lysis, releasing newly assembled virions. Occasionally, random fragments of the bacterial genome are...