Piperaceae, alkaloids

The preparation of a special chapter in this series on the constituents of pepper (6) led us to ignore pepper alkaloids. After publication of the chapter, we discovered that it dealt with the alkaloids of red pepper species (Capsicum, So-lanaceae), which are not pyrrolidines, and the purpose of this addendum is to provide a survey of the pyrrolidine alkaloids contained in black pepper species Piper, Piperaceae. 

The pungency of the fruits of black pepper (Piper nigrum Piperaceae), a widely used condiment, is mainly due to the piperidine alkaloid piperine (Figure 6.24). In this structure, the piperidine ring forms part of a tertiary amide structure, and is incorporated via piperidine itself, the reduction product of A1 -pipcridcine (Figure 6.22). 

Piperaceae, is cultivated for its fruit, which is usually dried, and used as a spice and seasoning. Black pepper has multiple uses in the processed food industry, in the kitchen, in perfumery, traditional medicine and even in beauty care. Pepper is valued for its pungency and flavour, which is attributed by the alkaloid piperine and the volatile oil. 

Cepharadione-A and -B have also been found in Piper auritum, an example of the rare occurrence of isoquinoline alkaloids in the family Piperaceae. A new dioxoaporphine is norcepharadione-B (46), isolated from the callus tissue of Stephania cepharantha. ... 

Piper guineense Schumach et Thonn West African black pepper, Ashanti pepper Piperaceae Neuromuscular activity, contraceptive, antiparasitic, aphrodisiac Abdominal disorders, chest complaints, used as an enema. Bronchitis, Headache, An1helmintic,Caries, diarrhea, hemorrhoids, antibiotic. Alkaloidal amide, 12, 16, 17... 

Vandopsis longicaulis Certain tumour-inhibitory plants of the Piperaceae and Rhizophoraceae families have yielded amides, e.g. A -dibydropiperine (9) occurs in Piper novae-hollandiae Miq. Macrocyclic alkaloids, e.g. azimine (10), have been fully defined. Further evidence for the nature of Lythrum bases has been obtained by synthesis of the overall skeleton. The key step in the synthesis involved formation of the 17-membered ring (11) (12). Directions for the isolation and degradation of piperine (9, with y,5-double bond) have been included in a unique laboratory text. ... 

Several representatives of the genus Piper (Piperaceae) are of economic importance. Some of these plants [e.g.. Piper nigrum (black pepper)] include alkaloids that are partially responsible for the desirable pungent and preservative properties of the plant. Other species are P. hetle (widely used as a masticatory), P. methysticum (widely used in the South Pacific as a soporific drug), and P. guineense (ashanti pepper). Most of these plants contain compounds that combine phenylpropanoid compounds see Chapter 8) and pyr-... 

Piperine (54) and antiepilepsirine (55), piperidine alkaloids that occur in Piper species (Piperaceae), are MAOIs with greater selectivity for MAO-B [173], yet they have not been studied extensively for therapeutic potential in PD. Some Vinca alkaloids, including vincristine, vinblastine, leurosine, and vindoline from Catharanthus roseus (L.) G.Don (Apocynaceae), are reported as selective MAO-B inhibitors, but cytotoxicity limits their development as potential drug candidates for PD [174, 175] (see Sect. 6) (Scheme 42.14). 

The most important alkaloids derived from piperidine (10-6) are alkaloids of black pepper Piper nigrum, Piperaceae). 

Alkamides are alkaloids of restricted distribution in plants. Although they have been isolated in more than 35 family plants, their presence is usually limited to obtain the individual alkamides in only a few milligrams. However, they are the most abundant components in Asteraceae, Solanaceae, Rutaceae, and Piperaceae families. Even within these four families, their presence is restricted to a few genera included within Anthemideae and Heliantheae tribes in Asteraceae, Capsicum in Solanaceae, Zanthoxylum and Glycosmis in Rutaceae, and Piper in Piperaceae. Stmcturally, alkamides possess an acidic and an amino moieties. Both acidic and amino moieties are characteristic depending on the plant family. 

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