Alkamides

Amides are compounds derived from carboxylic acids and amines, involving elimination of water (similar to ester formation from acids and alcohol). Amide functional groups are quite resistant to hydrolysis, and amide linkages between amino acids and peptides are essential to the stability of proteins. Acetaminophen, a well-known anti-inflammatory drug, is a simple amide formed from 4-hydroxy-phenylamine and acetic acid. 

In alkamides, amines are combined with unsaturated fatty acids by amide linkages, forming unbranched chains with one or more double and/or triple bonds. 

Alkamides are responsible for the sharp, burning or tingling taste associated with herbs and spices such as prickly ash bark (Zan-thoxylum spp.), black pepper (Piper nigrum). Echinacea angustifolia, E. purpurea and cayenne (Capsicum spp.). Capsicum oleoresin contains several phenolic amides including capsaicin. 

Isobutylamides are a subclass of alkamides based on the amine group 2-methylpropyl. They first aroused the interest of researchers for their insecticidal activities, being toxic to numerous classes of insects including the ubiquitous housefly and mosquito. Upon further investigation, it was obvious the most active insecticidal compounds were the ones that produced the most potent sialagogue (stimulating saliva flow) effects in humans (Brinker 1991/92). Isobutylamides so far investigated are derived from four plant families—Asteracea, Rutaceae, Piperaceae and Aristolochiaceae (see Table 8.3). 

Echinacea angustifolia, E. purpurea Spilanthes oleracea Achillea millefolium Chamaemelum nobile 

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Amides, Imides, Alkamides. When zirconium tetrachloride reacts with hquid ammonia, only one chloride is displaced to form a white precipitate, insoluble in hquid ammonia (227) ... 

Clifford, L.J. et al., Bioactivity of alkamides isolated from Echinacea purpurea (L.) Moench, Phytomedicine, 9, 249, 2002. 

The purple coneflower Echinacea purpura, and its close relatives, E. angustifolia and E. pallida, are the source of the herb Echinacea, which is widely popular as a nonspecific immune stimulant. These perennials are native to the prairies of North America and are now widely grown garden ornamentals. The root and aerial parts of the plant are the portions used, and the preparation s potency can be verified by the transient tingling sensation produced when it is tasted. Echinacea contains alkamides, caffeic acid esters (echinacoside, cichoric acid, caftaric acid), polysaccharides (heteroxylan), and an essential oil. Some echinacea products are standardized for their echinacoside content. In the past, adulteration with American feverfew (Parthenium integri-folium) was common. Echinacea is now sold either by itself or in combination with golden seal or zinc for the treatment of colds and influenza. 

In 2004, Ley et al. [45] showed a stereoselective enzymatic synthesis of cis-pellitorine [N-isobutyldeca-(2 ,4Z)-dienamide], a taste-active alkamide naturally occurring in tarragon. The reactants were ethyl ( ,Z)-2,4-decadienoate— the pear ester described before—and isobutyl amine. The reaction is catalysed by lipase type B from Candida antarctica (commercially available), which shows a remarkable selectivity towards the 2 ,4Z ester. The yield was about 80%. 

Bauer R, Foster S. Analysis of alkamides and caffeic acid derivatives from Echinacea simulata and E. paradoxa roots. Planta Med 1991 57 447-449. 

The three most widely used species of Echinacea are Echinacea purpurea, E pallida, and E angustifolia. The chemical constituents include flavonoids, lipophilic constituents (eg, alkamides, polyacetylenes), water-soluble polysaccharides, and water-soluble caffeoyl conjugates (eg, echinacoside, chicoric acid, caffeic acid). Within any marketed echinacea formulation, the relative amounts of these components are dependent upon the species used, the method of manufacture, and the plant parts used. Epurpurea has been the most widely studied in clinical trials. Although the active constituents of echinacea are not completely known, chicoric acid from E purpurea and echinacoside from E pallida and E angustifolia, as well as alkamides and polysaccharides, are most often noted as having immune-modulating properties. Most commercial formulations, however, are not standardized for any particular constituent. 

Emul P400, Comul S51, A 62, A 66, Alkamide DE 3405, and Alkamide DE 281E. 

Dodecylbenzene Sulfonic Acid Rhodapex NA-61 Alkamide DC 212/S Cheelox BF-13... 

Component Wt. Water 73. Sodium Metasi1icate-Pentahydrate 2. Mi ranol FBS 10. Rhodasurf 91-6 3. Cheelox BF-13 5. Alkamide DC-212/M 3. D-Limonene 2. 

Sodium Metasilicate, Anhydrous Cheelox NTA-Na3 Rhodafac RA-600 Alkamide 0C-212/S... 

Add Rhodafac RA-600, Alkamide 0C-212/S and Sodium Hydroxide, mixing after each addition. 

Charge water into mixing vessel and blend in Rhodapon SB-8208/S, tetrasodium EDTA, and Alkamide DC-212/S. Once system is uniform, blend in Butyl Cellosolve, Fragrance, Dye and Preservat i ve. 

Dissolve tetrasodium pyrophosphate in water, phosphate. Dissolve thoroughly. 2. Add Rhodafac LO-529 and Alkamide DC-212/S. 3. Add solvent. Physical Properties pH, as is 11.0 pH (1%) 9.0 Viscosity. 290 cps Specific Gravity 1.01 Formula FC-0054 Floor Cleaner Add trisodium Wt.%... 

Dissolve surfactants Igepal CO-630, Rhodapex CO-436 and Alkamide DC-212/S in water. 

Dodecylbenzene sulfonic Acid Rhodapex NA-61 Alkamide DC-212/S Rhodacal A-246/L Rhodasurf 25-9 Citric Acid (50%), to pH B Ethanol SD-3A Preservative... 

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