Acids cinnamic acid

Sodium hydroxide solution cannot be used at this stage since it may produce benzoic acid by the Cannizzaro reaction (Section IV,123) from any unchanged benzaldehyde. If, however, the reaction mixture is diluted with 3-4 volumes of water, steam distilled to remove the unreacted benzaldehyde, the residue may then be rendered alkaline with sodium hydroxide solution. A few grams of decolourising carbon are added, the mixture boiled for several minutes, and filtered through a fluted filter paper. Upon acidifying carefully with concentrated hydrochloric acid, cinnamic acid is precipitated. This is collected, washed and purified as above. 

The ionization of benzoic acids in water at 25° was used by Hammett as the standard reaction for the original qp treatment (2a). This reaction and several analogous reactions, e.g., ionization and ester saponification rates of benzoic acids, cinnamic acids, and phenylpropiolic acids, gives ap correlations of relatively high precision. Taft and Lewis classified such reactions in an A category (2f). Reexamination of these A reactions, as well as additional analogous data which have become available subsequently, provided eight reaction series of data of apparently comparable reliability. In the para position, each of these sets of data meets the necessary condition of a minimal basis set... 

CgHgOj a,g-Unsat acid Cinnamic acid (55) T162... 

Arcmatic compounds phenols, phenolic acids, cinnamic acid derivatives, coumarins, flavonoids, quinones, and tannins, all of which are aromatic compounds, comprise the largest group of secondary plant products. They are often referred to as "phenolics" and have been identified as allelopathic agents in more instances than all of the other classes of compounds combined 5). 

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. 

Work on the rate of dissolution of regular shaped solids in liquids has been carried out by Linton and Sherwood(1), to which reference is made in Volume 1. Benzoic acid, cinnamic acid, and /3-naphthol were used as solutes, and water as the solvent. For streamline flow, the results were satisfactorily correlated on the assumption that transfer took place as a result of molecular diffusion alone. For turbulent flow through small tubes cast from each of the materials, the rate of mass transfer could be predicted from the pressure drop by using the 1 j-factor for mass transfer. In experiments with benzoic acid, unduly high rates of transfer were obtained because the area of the solids was increased as a result of pitting. 

Benzoic acids 2-Hydroxybenzoic acids Phenylacetic acids Cinnamic acids Mandelic acids ... 

The biochemical mechanisms through which allelochemicals exert deleterious or toxic effects on plants are, for the most part, unknown (1). Some phenolic acids, cinnamic acids, coumarins, and flavonoids have been reported to inhibit photosynthesis and respiration of intact plants and microorganisms. However, the mechanisms, at the molecular level, through which the compounds interfere, remain to be ascertained. Some phenolic acids, coumarins, and flavonoids were reported to Inhibit C02-dependent 0 ... 

Cinnamic acid OH derivatives H J> H Caffeic acid / -Coumaric acid o-Coumaric acid CH Ferulic acid Cinnamic acid Sinapinic acid COOH Flavonoids Flavones Apigenin q JT 11 Luteolin R2 Flavanonol 1 i IJ R3 V >r (+)-Taxifolin OH 0... 

Glycine conjugation Glycine Acyl-CoA glycinetransferase (mitochondria) Acyl-CoA derivatives of carboxylic acids Salicylic acid, benzoic acid, nicotinic acid, cinnamic acid, cholic acid, deoxycholic acid... 

Daemonorops draco Blume. Xue Jie (resinous secretion from fruits) Amorphous dracoresene, amorphous dracoalban, benzoic acid, cinnamic acid, resin.49 Astringent, hemostatic, anticancer, for cancerous sores. 

N.A. Coumarins, bioflavonoids, mucilage, vitamins , , C, benzoic acid, cinnamic acid, coumarins, carotenoids.99121 Antiseptic, antirheumatic, antibacterial, antioxidant. 

N.A. Flavonoids, flavones, flavonols, flavanones, coumaric acid, cinnamic acid, terpenoids.190 Treat diabetes, high blood pressure, asthma. 

Styrene and its derivatives, such as a-methylstyrene, atropic acid, cinnamic acid, and cinnamyl alcohol, were readily reduced (acids were added as their salts), yielding the corresponding dihydro derivatives (Table I). However, propenyl-benzene, tmst/m-diphenylethylene, and stilbene absorbed no hydrogen. 

Hydrangenol is not the only chemical that acts in this manner. p-Coumaric acid, cinnamic acid, and / -hydroxyethylhydrazine (Figure 5) increased the activity of gibberellin applied to Meteor pea. 

Klumpp and co-workers362 have performed a detailed study of the acylation reactions of benzene with a variety of cinnamic acid derivatives in triflic acid. Cinnamic acids with alkyl or weakly electron-withdrawing groups (F, Br) on the phenyl ring give the corresponding substituted indanones as a result of a two-step... 

Kinetic data show that in seawater medium S42 reacts about 20-30 times faster than HS with acrylic acid, whereas the reaction of S42 with acrylonitrile is only about 4-6 times higher than with HS. However, in any environment, the importance of polysulfide versus bisulfide reactions is also dependent on their relative concentrations. In a situation where polysulfide and bisulfide ions are present in similar concentrations, our results imply that polysulfide ions, rather than bisulfide, are the important sulfur nucleophiles for reactions with activated unsaturated molecules having a terminal carboxyl group (e.g. acrylic acid, cinnamic acid). However, for neutral molecules such as fucoxanthin, in addition to polysulfide ions, reactions with bisulfide ions will also be of importance. 

Fig. (6). The shikimic acid-cinnamic acid pathway to steganes and podophyllotoxins...

This lactone derives from the shikimic acid-cinnamic acid pathway, via oxidative dimerization of coniferyl alcohol. Whereas the presence of yatein itself was not detected in the plants producing steganes, presteganes A and B were isolated in Steganotaenia araliaceae and constitute therefore viable biogenetic precursors [82,83]. 

Acetovanillone Vanillyl alcohol Vanilloylmethyl cetone p-Hydroxybenzaldehyde p-Hydroxybenzyl alcohol Vanillic acid p-Hydroxybenzoic acid Aliphatic acids Acetic acid Propanoic acid Isobutyric acid Butyric acid Isovaleric acid Valeric acid Hexanoic acid Heptanoic acid Octanoic acid 2-Heptenoic acid Nonanoic acid Dodecanoic acid Myristic acid Pentadecanoic acid Hexadecanoic acid 9-Hexadecanoic acid Heptadecanoic acid Stearic acid Oleic acid Linoleic acid Aromatic acids Benzoic acid Benzene propanoic acid Cinnamic acid (isomer 1) Cinnamic acid (isomer 2) Anisic acid Alcohols... 

Cinnamic Acid.—Cinnamic acid, investigated by Brester,5 showed a similar behavior in the electrolysis of both the free acid and the neutral solutions of its salts. Lob 6 has reported an accidental observation on the formation of bromstyrene by electrolysis of cinnamic acid in the presence of potassium bromide. 

Trans-olefins Examples Infrequent Pheromones Prostaglandins Common Fatty acids Cinnamic acids Chalcones, stilbenes... 

Tliis study describes the isolation and bioassay against insects of six compounds from the Peruvian plant Alchornea trlplinervia. The compounds anthranilic acid, cinnamic acid, and camphor showed significant inhibition of the growth of the tobacco budworm. Anthranilic acid, gentisic acid, senecioic acid, cinnamic acid, and cinnamaldehyde demonstrated low to moderate activity in the boll weevil antifeedant bioassay. Cinnamaldehyde, a constituent of the spice cinnamon, showed the highest level of inhibition to boll weevil feeding. 

Figure 3.1 Chemical structures of benzoic acid, cinnamic acid, and common phenolic acids.

Oxidative dimerization of cinnamic acids Cinnamic acid itself is stable to TTFA in the presence of BF3 etherate but 4-alkoxycinnamic acids are converted by these two reagents in TFA-CH2CI2 to fused bislactones by a nonphenolic oxidative dimerization (equation I). A few natural products of this type are known. 

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