Piperinic acid

M. Scholtz. Ladenburg and Scholtz used piperonal ( 8 ) and acetaldehyde (CH3CHO) to produce piperinic acid ( H 04), which was then reacted with thionyl chloride (COCl2) and piperidine (C5HUN) to produce piperine. 

DeCleyn and Verzele (3Q.3J-.32) isolated the four possible isomers from piperinic acid irradiated in an ultra-violet reactor, by counter-current distribution and also the piperidides obtained synthetically from the treated piperinic acid by high pressure liquid chromatography (figure 4). The structures of the isomers were derived mainly from NMR data. Their pungency was recorded, but possibly not by rigorous methods (31.32). The results confirmed the observation of Grewe t ail. (29) that piperine is the pungent principle of pepper, and that other isomers have little taste. ... 

Piperine is a yellow crystalline substance having a melting point of 128—130°C. Piperine, C17H1903N, was shown to be a weak base which, on hydrolysis with aqueous alkali or nitric acid, yielded a volatile base CjH N, later identified as piperidine. The acidic product of hydrolysis, piperine acid (C12H1904, m.p. 216-217°C), was shown to be 5-(3,4-methylene dioxy phenyl)-2,4, pentadienoic acid. 

Piperinic acid, T1 Piperitenone oxide, T4 Piperitols, T4 Piperitone, T2 Piperitone oxide, T4 Pipitzols, T1 Pisatin, Y3 Piscidic acid, A30 Plathyterpol, T39 Platicodigenin, T45 Platydesmine, K31 Platynecine, K22 Plicatic acid, Y7 Plinols, T3 Plumericin, T16 Plumieride, T16 Pluviine, K6 Podocarpic acid, T33 Podolactones, T38 Polyether antibiotics, Yll Polyporenic acid A, T50 Ponasterone, T48 Porantherine, K29 Porphyrins, Y23 Portentol, Y15 Portulal T40 Preisocalamendiol, T22 Pretoxin, T31 Pristimerin, T45 Pristimerol, T45 Proaporphine alkaloids, K3 Proline, All Prolinol, A17 Pronuciferine, K3 19-propylthevinol, K4 Prostaglandins, Y16 Protoaphins, YIO Protoemetine, K2 Protostanes, T50... 

Piperinic Acid and its Isomers.— The four isomers of piperinic acid have been formed by irradiation of piperinic acid (216), obtained from hydrolysis... 

Af-Phenylanthranilic acid 8812 Af-Phenylsulfanilic acid 8811 Piperinic acid 698... 

Piperinic acid, T1 Piperitenone oxide, T4 Piperitols, T4 Piperitone, T2 Piperitone oxide, T4 Pipitzols, T1 Piptamine, K6 ... 

Anderson first hydrolysed piperine by alkalis into a base and an acid, which were named by Babo and Keller piperidine and piperic acid respectively. The chemistry of these products is so well known that it need not be discussed here. The alkaloid was synthesised by Rugheimer by the action of piperoyl chloride on pijieridine. 

The chemistry of pepper has long been studied and the pungent principle of black pepper—a piperidine alkaloid, piperine 134—was isolated as early as 1877 (201). Its synthesis from the acid and piperidine was accomplished in 1882. (202). The corresponding pyrrolidine alkaloid trichostachyne (135) was isolated some 100 years later from several Piper species (see below). The cooccurence of piperidine and pyrrolidine alkaloids is a common feature of the chemistry of pepper. In many cases, the crude alkaloid extract is first cleaved with acids or bases and then each alkaloid is reconstituted by selective amidation. For the sake of unity, this chapter will be limited to comments on pyrrolidines, even in cases where they are minor alkaloids. 

Singh, J., Dubey, R.K., and Atal, C.K., Piperine-mediated inhibition of glucuronidation activity in isolated epithelial cells of the guinea-pig small intestine Evidence that piperine lowers the endogeneous UDP-glucuronic acid content, J. Pharmacol. Exp. Then, 236,488,1986. 

The chemistry of the pungent compounds of pepper has been under study since the isolation of piperine in 1820. Piperine was shown to be a piperidide of piperic acid, and had the trans. trans configuration. The three other possible isomers were soon postulated, and they were named isopiperine (cis.trans). isochavicine (trans. cis) and chavicine (cis.cis) even before they were synthesized. The assignment of the isomeric configuration starts from the amide end. 

Grewe et al (29) synthesised the four possible isomeric acids by stereospecific routes, as also the corresponding piperidides, and determined their spectral and other physical characteristics. This cleared the confusion in earlier works on the supposed isolation of chavicinic acids from pepper. They also determined their pungency and showed that, excepting piperine, 5(3,4-dioxymethylene phenyl)-2-trans.4-trans-pentadienoic acid, all other isomers are poorly pungent. They concluded that neither chavicine nor the other two, cis-trans or trans-cis. isomers exist in natural pepper. They also showed that most of the isomers were unstable to light and were easily converted into the trans.trans piperine. 

The pungency of black pepper [P. nigrum L.) was attributed initially to the presence of piperine only, the structure of which is trans,trans-5-(3,4-methylenedi-oxyphenyl)-2,4-pentadienoic acid piperidide. Further investigations into the pungency of this spice by several workers led to the discovery that materials other than piperine also contributed to its pungency (Traxler, 1971). 

Chun et al. (2002) found that 88% of the polysaccharide of black pepper berries was glucose, followed by galactose, arabin-ose, galacturonic acid and rhamnose in smaller proportions. Zachariah et al. (2005) evaluated major black pepper cultivars for oil, oleoresin and piperine, and the details are given in Table 2.4. The accumulation... 

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