Amino cinnamic acid

For the reduction of nitro-compounds containing a group which may be attacked by nascent hydrogen, as, for example, an aldehyde group, an unsaturated side chain, and so on, special methods must he applied. In such cases ferrous hydroxide or iron powder (cf. Chap. VII. 5, arsanilic acid) are often used. The reduction is carried out thus a weighed amount of ferrous sulphate is caused to act, in the presence of alkali (potassium or sodium hydroxide, baryta), on the substance to he reduced. In this way it is possible to reduce, for example, o-nitro-benzaldehyde to aminobenzaldehyde, and o-nitrocinnamic acid to amino-cinnamic acid. 

Nitro and Amino Cinnamic Acids.—Two other nitro aromatic acids and their corresponding amino acids should be mentioned all of which... 

Pschorr reaction. Synthesis of phenanthrene derivatives from diazotized a-aryl-omicron-amino-cinnamic acids by intramolecular arylation. 

C1SH 2 mol wt 228.29. C 94.70%, H 5.30%. Synthesis by a Pschorr reaction from diazotized -(2-naphthyl)-2-amino-cinnamic acid Cook, J. Chem. Soc. 193t, 2524. From di-phenylmethylsoccinic anhydride Heweit, J. Chem. Soe. 

A new diphosphine ligand, Norphos , catalyses the reduction of Z-a-(acetyl-amino)cinnamic acids to the expected dihydrocinnamic acids with optical yields of ca. 96%. ° The ligand is prepared from trans-vinylidenebis(diphenylphosphine oxide) by a Diels-Alder reaction with cyclopentadiene, classical resolution using (L)-(-)-dibenzoyltartaric acid, and finally reduction. The same substrates can also be reduced in ca. 80% optical yields using diphosphine ligands derived from enantiomerically pure menthoP or mandelic acid. ... 

Feeding experiments with tritiated /7-aminophenylalanine (153),/>-amino-cinnamic acid (152), / -aminobenzoic acid, and / -aminophenylserine (154) showed that both (153) and (154) [but not (152) or / -NH2CgH4C02H] are involved in the biosynthesis of the nitroaromatic portion of (155), which suggested the partial route outlined in Scheme 11. Studies by Yamazaki et al. of the incorporation of L-methionine into (155) showed that the four extra methyl groups in the side-chain are not derived from methionine, which thus ruled out an acetate-malonate route (a) to the side-chain in aureotine. In fact, C n.m.r. studies showed that the extra methyls in (155) were all derived from the methyl of propionate, but since both acetate and propionate are incorporated, the Japanese workers consider that an acetate-propionate route (b) to the side chain is most probable. 

The earliest references to cinnamic acid, cinnamaldehyde, and cinnamyl alcohol are associated with thek isolation and identification as odor-producing constituents in a variety of botanical extracts. It is now generally accepted that the aromatic amino acid L-phenylalanine [63-91-2] a primary end product of the Shikimic Acid Pathway, is the precursor for the biosynthesis of these phenylpropanoids in higher plants (1,2). 

Radicaloid substitution has not been extensively studied in the thiophene series. Molecular orbital calculations indicate that substitution should occur in the a-position. This has been found to be the case in the Gomberg-Bachmann coupling of diazohydroxides with thiophenes which has been used for the preparation of 2-(o-nitro-phenyl) thiophene, 2-(p-toluyl) thiophene, " " and 2-(p-chloro-phenyl)thiophene. " Coupling in the /8-position has been used for the preparation of 1,3-dimethyl-4,5-benzisothionaphthene (148) from 2-amino-tt-(2,5-dimethyl-3-thienyl)cinnamic acid (149). A recent investigation describes the homolytic phenylation of 2- and 3-phenyl-... 

In recent years, the catalytic asymmetric hydrogenation of a-acylamino acrylic or cinnamic acid derivatives has been widely investigated as a method for preparing chiral a-amino acids, and considerable efforts have been devoted for developing new chiral ligands and complexes to this end. In this context, simple chiral phosphinous amides as well as chiral bis(aminophosphanes) have found notorious applications as ligands in Rh(I) complexes, which have been used in the asymmetric hydrogenation of a-acylamino acrylic acid derivatives (Scheme 43). 

Phenylalanine ammonia-lyase (PAL EC 4.3.1.5) is a pivotal enzyme in controlling flow of carbon from aromatic amino acids to secondary aromatic compounds (Figure 1) (28). PAL primarily deaminates phenylalanine to form t-cinnamic acid, however, in many species, it also less efficiently deaminates tyrosine to form -coumaric acid. Because PAL is restricted to plants and is an important enzyme in plant development, Jangaard (29) suggested that PAL inhibitors might make safe and effective herbicides, however, in his screen of several herbicides, he found no compound to have a specific effect on PAL. This was also the case in studies by Hoagland and Duke (30, 31.) in which 16 herbicides were screened. 

The major substrates for amino acid conjugation are benzoic acid and related aromatic carboxylic acids such as phenylacetic acid, phenoxyacetic acid, cinnamic acid, etc. (21). In humans, the major amino acid utilized in the conjugation is glycine however, glutamine and taurine can also be cofactors. In birds, the major amino acid utilized is ornithine. 

Thus, G. Oehme et al. employed two types of polysoaps in the micellar catalytic asymmetric hydrogenation of cinnamic acid acetamidates as amino acid precursors [81, 82]. 

Phenylalanine Ammonia-Lyase. The building units of lignin are formed from carbohydrate via the shikimic acid pathway to give aromatic amino acids. Once the aromatic amino acids are formed, a key enzyme for the control of lignin precursor synthesis is phenylalanine ammonia-lyase (PAL) (1). This enzyme catalyzes the production of cinnamic acid from phenylalanine. It is very active in those tissues of the plant that become lignified and it is also a central enzyme for the production of other phenylpropanoid-derived compounds such as flavonoids and coumarins, which can occur in many parts of the plant and in many different organs (35). Radioactive phenylalanine and cinnamic acid are directly incorporated into lignin in vascular tissue (36). 

Cinnamic acids may condense with molecules other than quinic acid, including rosmarinic, malic and tartaric acid, aromatic amino acids, choline, mono- and polysaccharides, glycerol, myo-inositol, and different glycosides (anthocyanins, flavonols and diterpenes) [13]. 

Glasses have also been reported for nematic p-methoxybenzylidene-p-n-butyl-aniline 66) and some commercial liquid crystals 67) and for smectic ethyl-(p-anisol-amino)-cinnamate 68), p-n-hexyloxybenzylidene-p-aminobenzoic acid (Tg = 376 K) and p-n-nonyloxybenzylidene-p-aminobenzoic acid (Tg = 203 K) 69). 

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