Phenylpropane derivatives

Gracza, L. 1981. In vitro study of the expectorant effect of phenylpropane derivatives of hazelwort. XII. Active substances from Asarum europaeum L. Planta Med. 42 155-159. 

Phenylpropane derivatives The name given to compounds of phenol that have a three-carbon-atom (propyl) chain attached those most commonly found in essential oils are thymol, carvacrol, chavicol (see Phenols). 

Based on Klason lignin content. Yield of phenylpropane derivatives. 

Oprean, R. Oprean, L. Tamas, M. Sandulescu, R. Roman, L. Essential oils analysis. II. Mass spectra identification of terpene and phenylpropane derivatives. J. Pharm. Biomed. Anal. 2001, 24, 1163-1168. 

Sinha, A. K. Joshi, B., P. Dogra, R. Process for the Preparation of Substituted trare.s-Cinnamaldehyde, a Natural Yellow dye, from Phenylpropane Derivatives 2003 US 6,566,557... 

All flavouring and fragrance materials which are comparatively volatile are easily soluble (1-10% by weight), e.g. monoterpenes, phenylpropane derivatives and sesquiterpenes not only the hydrocarbons but also the oxygenated molecules like ethers, esters, ketones, lactones and alcohols. Ah of which are typical components of essential oils. 

Fennel oils are composed mainly of phenylpropane derivatives, the different anethol isomers making up 60-80% of the oil, followed by fenchone, a bicyclic monoterpene lactone making up 10-35%, and monoterpene hydrocarbons, mainly limonene, with a content of up to 10%. 

As already mentioned, the oxygen atoms in phenylpropane derivatives originate from different sources (CO2,02, H2O) with different 8 0-values. Nevertheless, the average range found for natural aromates of 8 0-values varies from -i-lO to -i-15%o (Table 6.5). 

Several products are formed when phenylcyclopropane is irradiated in acetonitrile with added trifluoromethylsulfenyl chloride. The phenylpropane derivative (284) is one of the products and its formation can be rationalised by attack of a chlorine atom, formed by S-Cl bond fission, on the cyclopropane to yield the radical (285) which combines with a trifluoromethylthio radical to give the product. cw-Stereoselective addition of benzenesulfonyl bromide occurs to the tricycloheptane (286) on irradiation and the two products (287) and (288) are formed in a ratio of 3 1... 

Mercury salts have previously been shown to be capable of cleaving cyclopropyl bonds. Phenyl-substituted cyclopropanes react with mercury(II) acetate to give 3-mercurio-l-methoxy-l-phenylpropane derivatives, which can undergo further reactions such as reduction with sodium borohydride or addition to alkenes. For example, treatment of phenyl-cyclopropane (1) with mercury(II) acetate in methanol, followed by the addition of sodium chloride, produced 3-(chloromercurio)-l-methoxy-l-phenylpropane(2) in good yield.When the primary mercury adduct was reacted with alkenes without isolation, the yields were lower than those in the two-step transformation. ... 

In one group of essential oils the phenylpropane derivatives (from shikimic acid) dominate in another group mono-, sesqui- and diterpenes are the dominant substances. 

When a balsam is distilled, a volatile oil and a resin are obtained. This latter is an amorphous mass, which is softened by heating and melts to a clear, viscous and sticky liquid. A typical balsam is biosynthetically related to the terpenes and phenylpropane derivatives of volatile oils. Balsams are found in several plant families, e.g. Anacardiaceae,... 

Essential oils are volatile, odorous principles consisting of terpene alcohols, aldehydes, ketones and esters (>90%) and/or phenylpropane derivatives. Aetherolea are soluble in ethanol, but only to a very limited extent in water. They are mostly obtained by steam distillation of plant material. 

After treal me.nt with the VS reagent the monoterpene alcohols and their ester.s, cineole, the aldehyde ciiral and dironellal show blue or blue-vialei colour in vis. The phenylpropane derivatives safrole, anethole, myristidn, apioi and eitgenol are brown-red/ violet, while thymol and carvon are red to red-violet pipedtone shows a typical orange colour. 

All phenylpropane derivatives of Myristkac (1) and Petroselini aeth. (2) are seen as quenching zones in UV-254 nm (-aA) and as brown to red-brown-coloured zones with VS reagent in vis, (—>B). 

Finally, in the more polar fraction of H. perforatum, amino acids as well as ubiquitous phenylpropane-derived compounds were found [7]. Chlorogenic acid and caffeic acid have been reported as individual phenylpropane components. 

FIGURE 5 Partial structure of lignin, which is a polyphenol built up from units of phenylpropane derivatives (Fig. 4) by condensation and dehydrogenation within the plant. Condensation points, lignin precursors via ether, and C-C bonds are indicated. Modihed after Killops and Killops (1993). 

Composition Genuine essential oils consist exclusively of volatile components with boiling points mainly between 150 and 300 °C. They contain predominantly hydrocarbons or monofunctional compounds such as aldehydes, alcohols, esters, ethers, and ketones. Parent compounds are mono- and sesquiterpenes, phenylpropane derivatives, and longer-chain aliphatic compounds. Accordingly, essential oils are relative non-polar mixtures, i.e., they are soluble in most organic solvents. Often the organoleptic properties are not determined by the main components but by minor and trace compounds such as, e.g., 1,3,5-undecatrienes and pyrazines in galbanum oil. In many of the commercially important oils, the number of identified components exceeds 100. Very many of the constituents are chiral, frequently one isomer predominates or is exclusively present, e. g., (- )-menthol in peppermint oils or (-)-linalyl acetate in lavender oil. 

At present mainly terpenes and aromatic compounds have been isolated and identified as components of resins with diterpenes (less frequently sesquiterpenes and triterpenes) and phenylpropane derivatives usually dominating. 

Flavor substances are generally volatile and easily deteriorate. Most (e.g., tespenoids and phenylpropan derivatives) form stable complexes with CDs. and in dry... 

Recent chemotaxonomlc investigations on phenylpropane derivatives show the existence of species-specific flavonoid patterns in bud exudates and the wide distribution of the secretion of lipophilic phenols in the... 

Extension of the enamine-mediated carbonyl a-amination strategy to the generation of quaternary stereogenic centers at the a-position of a-branched aldehydes under catalysis by prohne 1 [8, 9], pyrrolidine tetrazole 3 [10, 11], or L-azetidin-2-carboxylic acid 4 [8] has also been explored (Table 11.1). The observed enantio-selectivities ranged from essentially none to >99%. Derivatives of 2-phenylpropanal gave better enantioselectivities than a,a-dialkyl substituted aldehydes. Erase and coworkers [11] employed microwave irradiation to accelerate the rate of proline-catalyzed amination, and found that yields as well as enantioselectivity can be somewhat improved with shorter reaction times. It appears that the pyrrolidine tetrazol 3 was a more effective catalyst than L-proline 1 for the amination of 2-phenylpropanal derivatives [10,11]. Subsequent reduction of adducts and cyclization could be carried out to afford the respective a-amino alcohols or the A-amino-oxazolidinones. 

Phenylpropane derivatives Emetine (D 22.1.2) Antiamebic, expectorant and emetic... 

The majority of these phenols are also phenylpropane derivatives— many are prominent constituents of common spices such as cloves, aniseed, celery seed, basil and tarragon. 

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