In chemistry, an ester is a compound derived from an acid in which the hydrogen atom (H) of at least one acidic hydroxyl group of that acid is replaced by an organyl group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well, but not according to the IUPAC.
In organic chemistry, the Swern oxidation, named after Daniel Swern, is a chemical reaction whereby a primary or secondary alcohol is oxidized to an aldehyde or ketone using oxalyl chloride, dimethyl sulfoxide (DMSO) and an organic base, such as triethylamine. It is one of the many oxidation reactions commonly referred to as 'activated DMSO' oxidations. The reaction is known for its mild character and wide tolerance of functional groups.
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.
1-Hexanol (IUPAC name hexan-1-ol) is an organic alcohol with a six-carbon chain and a condensed structural formula of CH3(CH2)5OH. This colorless liquid is slightly soluble in water, but miscible with diethyl ether and ethanol. Two additional straight chain isomers of 1-hexanol, 2-hexanol and 3-hexanol, exist, both of which differing by the location of the hydroxyl group. Many isomeric alcohols have the formula C6H13OH. It is used in the perfume industry.
Chemical ecology is the study of chemically mediated interactions between living organisms, and the effects of those interactions on the demography, behavior and ultimately evolution of the organisms involved. It is thus a vast and highly interdisciplinary field. Chemical ecologists seek to identify the specific molecules that function as signals mediating community or ecosystem processes and to understand the evolution of these signals. The substances that serve in such roles are typically small, readily-diffusible organic molecules, but can also include larger molecules and small peptides.
An aroma compound, also known as an odorant, aroma, fragrance or flavoring, is a chemical compound that has a smell or odor. For an individual chemical or class of chemical compounds to impart a smell or fragrance, it must be sufficiently volatile for transmission via the air to the olfactory system in the upper part of the nose. As examples, various fragrant fruits have diverse aroma compounds, particularly strawberries which are commercially cultivated to have appealing aromas, and contain several hundred aroma compounds.
cis-3-Hexen-1-ol, also known as (Z)-3-hexen-1-ol and leaf alcohol, is a colorless oily liquid with an intense grassy-green odor of freshly cut green grass and leaves. It is produced in small amounts by most plants and it acts as an attractant to many predatory insects. cis-3-Hexen-1-ol is a very important aroma compound that is used in fruit and vegetable flavors and in perfumes. The yearly production is about 30 tonnes.
Dimethyl sulfide (DMS) or methylthiomethane is an organosulfur compound with the formula (CH3)2S. The simplest thioether, it is a flammable liquid that boils at 37 °C (99 °F) and has a characteristic disagreeable odor. It is a component of the smell produced from cooking of certain vegetables, notably maize, cabbage, beetroot, and seafoods. It is also an indication of bacterial contamination in malt production and brewing. It is a breakdown product of dimethylsulfoniopropionate (DMSP), and is also produced by the bacterial metabolism of methanethiol.
Salicylic aldehyde (2-hydroxybenzaldehyde) is the organic compound with the formula () C6H4CHO-2-OH. Along with 3-hydroxybenzaldehyde and 4-hydroxybenzaldehyde, it is one of the three isomers of hydroxybenzaldehyde. This colorless oily liquid has a bitter almond odor at higher concentration. Salicylaldehyde is a key precursor to a variety of chelating agents, some of which are commercially important.
2-Undecanone, also known as methyl nonyl ketone and IBI-246, is the organic compound with the formula CH3C(O)C9H19. It a colorless oil. It is usually produced synthetically, but it can also be extracted from various plant sources, including from essential oil of rue. It is found naturally in bananas, cloves, ginger, guava, strawberries, wild-grown tomatoes, and the perennial leaf vegetable Houttuynia cordata.
3-Mercapto-3-methylbutan-1-ol, also known as MMB, is a common odorant found in food and cat urine. The aromas ascribed to MMB include catty, roasty, broth-like, meaty, and savory, or similar to cooked leeks.
Heptanal or heptanaldehyde is an alkyl aldehyde. It is a colourless liquid with a strong fruity odor, which is used as precursor to components in perfumes and lubricants.
Phenylacetaldehyde is an organic compound used in the synthesis of fragrances and polymers. Phenylacetaldehyde is an aldehyde that consists of acetaldehyde bearing a phenyl substituent; the parent member of the phenylacetaldehyde class of compounds. It has a role as a human metabolite, a Saccharomyces cerevisiae metabolite, an Escherichia coli metabolite and a mouse metabolite. It is an alpha-CH2-containing aldehyde and a member of phenylacetaldehydes.
2-Methyl-1-butanol (IUPAC name, also called active amyl alcohol) is an organic compound with the formula CH3CH2CH(CH3)CH2OH. It is one of several isomers of amyl alcohol. A colorless liquid, it occurs naturally in trace amounts and has attracted some attention as a potential biofuel, exploiting its hydrophobic (gasoline-like) and branched structure. It is chiral.
Ethyl propionate is an organic compound with formula C2H5O2CCH2CH3. It is the ethyl ester of propionic acid. It is a colorless volatile liquid with a pineapple-like odor. Some fruits such as kiwis and strawberries contain ethyl propionate in small amounts.
Green leaf volatiles (GLV) are volatile organic compounds that are released when plants suffer tissue damage. Specifically, they include aldehydes, esters, and alcohols of 6-carbon compounds released after wounding. These compounds are very quickly produced and emitted, and are used by nearly every green plant. Plants constantly release GLVs, but un-stressed plants release them in much smaller amounts. Some of these chemicals act as signaling compounds between either plants of the same species, of other species, or even vastly different lifeforms like insects. Some, although not necessarily all, of these chemicals act essentially as plant pheromones.[12] GLVs also have antimicrobial properties to prevent infection at the site of injury.
6-Nonenal is an organic compound with the formula C2H5CH=CH(CH2)4CHO. Other isomeric nonenal compounds are also known to exist naturally, e.g. 2-nonenal. The cis-isomer of 6-nonenal is often listed as the principal component in the aromas of muskmelon fruits. The trans-isomer is listed as an off-flavor aroma of milk foams, and thought to be a possible polypropylene odorant.
4-Methylcyclohexanemethanol (MCHM, systematic name 4-methylcyclohexylmethanol) is an organic compound with the formula CH3C6H10CH2OH. Classified as a saturated higher alicyclic primary alcohol. Both cis and trans isomers exist, depending on the relative positions of the methyl (CH3) and hydroxymethyl (CH2OH) groups on the cyclohexane ring. Commercial samples of MCHM consists of a mixture of these isomers as well as other components that vary with the supplier.
trans,cis-2,6-Nonadienal is an organic compound that is classified as a doubly unsaturated derivative of nonanal. The molecule consists of a α,β-unsaturated aldehyde with an isolated alkene group. The compound has attracted attention as the essence of cucumbers, but it is also found in bread crust and freshly cut watermelon.
The smell of freshly cut grass is an odour caused by green leaf volatiles (GLVs) released by damaged grass. Mechanical damage from activities such as lawnmowing results in the release of cis-3-hexenal and other compounds that contribute to a grassy or "green" smell. cis-3-Hexenal has a low odour detection threshold that humans can perceive at concentrations as low as 0.25 parts per billion.
