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Nepetalactone Isomers
Nepetalactone is a name for multiple iridoid analog stereoisomers. Nepetalactones are produced by ''Nepeta cataria'' (catnip) and many other plants belonging to the genus ''Nepeta'', in which they protect these plants from herbivorous insects by functioning as insect repellents. They are also produced by many aphids, in which they are sex pheromones. Nepetalactones are cat attractants, and cause the behavioral effects that catnip induces in domestic cats. However, they affect visibly only about two thirds of adult cats. They produce similar behavioral effects in many other felids, especially in lions and jaguars. In 1941, the research group of Samuel M. McElvain was the first to determine the structures of nepetalactones and several related compounds. Structure and properties Nepetalactone has three chiral centers, two at the fusion of the two rings, and one where the methyl group attaches to the cyclopentane ring. Thus, it has eight (23) stereoisomers. The terms ''cis'' and ''tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iridoid
Iridoids are a type of monoterpenoids in the general form of cyclopentanopyran, found in a wide variety of plants and some animals. They are biosynthetically derived from 8-oxogeranial. Iridoids are typically found in plants as glycosides, most often bound to glucose. The chemical structure is exemplified by iridomyrmecin, a defensive chemical produced by the ant genus ''Iridomyrmex'', for which iridoids are named. Structurally, they are bicyclic ''cis''-fused cyclopentane-pyrans. Cleavage of a bond in the cyclopentane ring gives rise to a subclass known as ''secoiridoids'', such as oleuropein and amarogentin. Occurrence The iridoids produced by plants act primarily as a defense against herbivores or against infection by microorganisms. The variable checkerspot butterfly also contains iridoids obtained through its diet which act as a defense against avian predators. To humans and other mammals, iridoids are often characterized by a deterrent bitter taste. Aucubin and catal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Group
In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many organic compounds. It is a very stable group in most molecules. While the methyl group is usually part of a larger molecule, bounded to the rest of the molecule by a single covalent bond (), it can be found on its own in any of three forms: methanide anion (), methylium cation () or methyl radical (). The anion has eight valence electrons, the radical seven and the cation six. All three forms are highly reactive and rarely observed. Methyl cation, anion, and radical Methyl cation The methylium cation () exists in the gas phase, but is otherwise not encountered. Some compounds are considered to be sources of the cation, and this simplification is used pervasively in organic chemistry. For example, protonation of methanol gives an elect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the substance and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geranyl Pyrophosphate
Geranyl pyrophosphate (GPP), also known as geranyl diphosphate (GDP), is the pyrophosphate ester of the terpenoid geraniol. Its salts are colorless. It is a precursor to many natural products. Occurrence GPP is an intermediate in the isoprenoid biosynthesis pathway that produces longer prenyl chains such as farnesyl pyrophosphate and geranylgeranyl pyrophosphate as well as many terpenes. It can be prepared in the laboratory from geraniol. Related compounds * Geraniol * Farnesyl pyrophosphate * Geranylgeranyl pyrophosphate See also * Dimethylallyltranstransferase Dimethylallyltranstransferase (DMATT), also known as farnesylpyrophosphate synthase (FPPS) or as farnesyldiphosphate synthase (FDPS), is an enzyme that in humans is encoded by the FDPS gene and catalyzes the transformation of dimethylallylpyr ... References Further reading *Kulkarni RS, Pandit SS, Chidley HG, Nagel R, Schmidt A, Gershenzon J, Pujari KH, Giri AP and Gupta VS, 2013Characterization of three n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geranyl Pyrophosphate
Geranyl pyrophosphate (GPP), also known as geranyl diphosphate (GDP), is the pyrophosphate ester of the terpenoid geraniol. Its salts are colorless. It is a precursor to many natural products. Occurrence GPP is an intermediate in the isoprenoid biosynthesis pathway that produces longer prenyl chains such as farnesyl pyrophosphate and geranylgeranyl pyrophosphate as well as many terpenes. It can be prepared in the laboratory from geraniol. Related compounds * Geraniol * Farnesyl pyrophosphate * Geranylgeranyl pyrophosphate See also * Dimethylallyltranstransferase Dimethylallyltranstransferase (DMATT), also known as farnesylpyrophosphate synthase (FPPS) or as farnesyldiphosphate synthase (FDPS), is an enzyme that in humans is encoded by the FDPS gene and catalyzes the transformation of dimethylallylpyr ... References Further reading *Kulkarni RS, Pandit SS, Chidley HG, Nagel R, Schmidt A, Gershenzon J, Pujari KH, Giri AP and Gupta VS, 2013Characterization of three n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terpenoid
The terpenoids, also known as isoprenoids, are a class of naturally occurring organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeably with "terpenes", terpenoids contain additional functional groups, usually containing oxygen. When combined with the hydrocarbon terpenes, terpenoids comprise about 80,000 compounds. They are the largest class of plant secondary metabolites, representing about 60% of known natural products. Many terpenoids have substantial pharmacological bioactivity and are therefore of interest to medicinal chemists. Plant terpenoids are used for their aromatic qualities and play a role in traditional herbal remedies. Terpenoids contribute to the scent of eucalyptus, the flavors of cinnamon, cloves, and ginger, the yellow color in sunflowers, and the red color in tomatoes. Well-known terpenoids include citral, menthol, camphor, salvinorin A in the plant '' Salvia di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoterpene
Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. Monoterpenes may be linear (acyclic) or contain rings (monocyclic and bicyclic). Modified terpenes, such as those containing oxygen functionality or missing a methyl group, are called monoterpenoids. Monoterpenes and monoterpenoids are diverse. They have relevance to the pharmaceutical, cosmetic, agricultural, and food industries. Biosynthesis Monoterpenes are derived biosynthetically from units of isopentenyl pyrophosphate, which is formed from acetyl-CoA via the intermediacy of mevalonic acid in the HMG-CoA reductase pathway. An alternative, unrelated biosynthesis pathway of IPP is known in some bacterial groups and the plastids of plants, the so-called MEP-(2-methyl-D-erythritol-4-phosphate) pathway, which is initiated from C5 sugars. In both pathways, IPP is isomerized to DMAPP by the enzyme isopentenyl pyrophosphate isomerase. Geranyl pyrophosphate is the precurso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nepetalactol
Nepetalactol is an iridoid. It is produced from 8-oxogeranial by the enzyme iridoid synthase. Nepetalactol is a substrate for the enzyme iridoid oxidase (IO) which produces 7-deoxyloganetic acid. It has been identified in ''Actinidia polygama ''Actinidia polygama'' (also known as , silver vine, , and cat powder) is a species of kiwifruit in the Actinidiaceae family. It grows in the mountainous areas of Korea, Japan and China at elevations between . Silver vine can reach up to high ...'' (the silver vine) as a major cat attractant, and a mosquito repellent. The fact that mosquitos bite cats with nepetalactol on their fur less often may explain why cats are attracted to silver vine in the first place. References {{Reflist Iridoids Cyclopentanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinidine
Actinidine is an iridoid produced in nature by a wide variety of plants and animals. It was the first cyclopentanoid monoterpene alkaloid to be discovered. It is one of several compounds that may be extracted from the valerian (''Valeriana officinalis'') root and silver vine (''Actinidia polygama''), as well as several types of insects in the larval and imaginal stages. Actinidine is a cat attractant, with effects like those of nepetalactone, the active compound found in catnip. Certain species of stick insects, including ''Megacrania batesii'' and ''Megacrania tsudai'', possess a chemical defense mechanism which involves the secretion of an actinidine-containing substance from the prothoracic The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum (dorsal), the prosternum (ventral), and the propleuron (lateral) on ea ... glands, when threatened by a pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lonicera Tatarica
''Lonicera tatarica'' is a species of honeysuckle known by the common name Tatarian honeysuckle. Native to Eurasia, the plant is one of several exotic bush honeysuckles present in North America, being considered an invasive species there. Description ''Lonicera tatarica'' is a bushy shrub which may approach in height. The twigs can be an array of colors from green to brown with a hollow brown pith. The plant is lined with oval or rounded simple leaves long. The leaves and stem range from long, wide. They are egg shaped and both hairless and toothless. The inflorescence ranges in color from deep rose to light pink, and can also be white. The petals are typically long, with a slender tube and 2 lips. The upper lip contains 4 lobes, the middle two erect and fused near the base. The white to pink to crimson red flowers are each about long, their stamens and styles protruding. The fruit is a shiny orange or red seed-containing berry up to 1'' ''cm wide. The berries are attr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refractive Index
In optics, the refractive index (or refraction index) of an optical medium is a dimensionless number that gives the indication of the light bending ability of that medium. The refractive index determines how much the path of light is bent, or refracted, when entering a material. This is described by Snell's law of refraction, , where ''θ''1 and ''θ''2 are the angle of incidence and angle of refraction, respectively, of a ray crossing the interface between two media with refractive indices ''n''1 and ''n''2. The refractive indices also determine the amount of light that is reflected when reaching the interface, as well as the critical angle for total internal reflection, their intensity ( Fresnel's equations) and Brewster's angle. The refractive index can be seen as the factor by which the speed and the wavelength of the radiation are reduced with respect to their vacuum values: the speed of light in a medium is , and similarly the wavelength in that medium is , where ''Π... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MmHg
A millimetre of mercury is a manometric unit of pressure, formerly defined as the extra pressure generated by a column of mercury one millimetre high, and currently defined as exactly pascals. It is denoted mmHg or mm Hg. Although not an SI unit, the millimetre of mercury is still routinely used in medicine, meteorology, aviation, and many other scientific fields. One millimetre of mercury is approximately 1 Torr, which is of standard atmospheric pressure ( ≈ ). Although the two units are not equal, the relative difference (less than ) is negligible for most practical uses. History For much of human history, the pressure of gases like air was ignored, denied, or taken for granted, but as early as the 6th century BC, Greek philosopher Anaximenes of Miletus claimed that all things are made of air that is simply changed by varying levels of pressure. He could observe water evaporating, changing to a gas, and felt that this applied even to solid matter. More cond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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