Hydroxycinnamic acid amides

The ipobscurines were only present in mature seeds. Neither flowers and undeveloped fruits nor epigeal vegetative parts and roots show any of these alkaloids. These compounds are synthesized apparently in the late phase of the seed development. Their biosynthesis probably proceeds as follows tryptamine — serotonin — N, -(p-coumaroyl)serotonin (ipobscurine A) — B — C/D (Jenett-Siems et al. 2003). 

Ipobscurines could not be detected in 150 convolvulaceous species belonging to 23 genera with one exception Seeds of I. ochracea (Lindl.) G.Don, another paleo-tropic perennial herb found throughout tropical Africa (Eich, unpublished results). This is interesting from the chemotaxonomic point of view, since I. obscura and I. ochracea are closely related species. They were shown to be sisters with 100% support in a DNA-based cladistic analysis (ITS and waxy sequences Miller et al. 1999). In the traditional classification both are nested within sect. Erpipomoea Choisy (Austin and Hudman 1996). 

Occurrence in the Solanaceae. As already mentioned above, mono-acylated HCA conjugates of putrescine were detected as constituents of Solanum lycoper-sicum sub nom. Lycopersicum esculentum, Nicotiana tabacum, and Petunia x hybrida (Martin-Tanguy et al. 1978)  

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Important hydroxycinnamic acid conjugates from plants are hydroxycin-namic acid esters and hydroxycinnamic acid amides (see Petersen et al, 1999). 

Coumarins are known to react with amines to give various products, for example 2,3-dihydrobenzofurans. 3-Bromocoumarin has been shown to give the benzofuran (194) on heating with piperidine but coumarin itself gave 2 -hydroxycinnamic acid amides. The behaviour of coumarin-3-carboxylic acid with amines depends on the ratio of reactants and the temperature. When 8-acetyl-7-hy(iroxy-4-methylcoumarin was subjected to a Mannich reaction, the benzodipyran (195) was formed in 80% yield.Several other tricyclic products have been prepared from coumarins for example, the... 

Cabanne, F., M. a. Delebroux, J. Martin-Tanguy, and C. Martin, Hydroxycinnamic acid amides and ripening to flower of Nicotiana tabacum var. xanthi n. c Physiol. Plant, 53,399-404 (1981). 

Hydroxycinnamic acid amides (Fig. 52.1), proanthocyanidins, and flavonol-glycosides are the largest groups of phenolic compounds in cocoa seeds. 

Facchini PJ, Hagel J, Zulak KG (2002) Hydroxycinnamic acid amide metabolism physiology and biochemistry. Can J Bot 80 577-589... 

Erratically occurring specific secondary metabolites, e.g., (i) 3-carbolines in both families (Sect. 4.1), (ii) cardenolides (Sect. 7.9.2), in the Solanaceae or (iii) 2-alkylpiperidines (animartinines Sect. 5.2.2), serotonin-hydroxycinnamic acid amides (ipobscurines Sect. 6.7.4) in the Convolvulaceae, are not taken into consideration here. 

Sattar EA, Glasl H, Nahrstedt A, Hilal SH, Zaki AY, El-Zalabani SMH (1990) Hydroxycinnamic acid amides from lochroma cyaneum. Phytochemistry 29 3931-3933 Sattar EA, Gala A, Rashwan O (1995) Caffeoyl derivatives from the seeds of Ipomoea fistulosa. Int J Pharmacog 33 155-158... 

We will quote here the identification of the amides of tyrosine and tryptophan with caffeic (Section 5,H.86) and />coumaric acids (Section 5,H.84) (see in Section 5,H, hydroxycinnamic acids). 

A hydroxycinnamic acid-spermidine amide has been isolated from the drug Crataegi flos, which is raw material prepared from the flowers of a Crataegus subspecies and is reported to have cardiotoxic properties. Chemical and spectroscopic methods have indicated that this amide is iV, A, A -tri-4-( )-coumaroylspermidine (87). Also, the occurrence of this amide in flowers of various members of the Rosaceae has been investigated... 

Hydroxybenzyl alcohol, 2888 6-Hydroxycaespitol, 2892 Hydroxycinnamates, 1549 Hydroxy cinnamic acid amides, 1604 Hydroxycinnamic acids, 1953, 2346, 2589 Hydroxycitronellal, 2999... 

For ipobscurines, hydroxycinnamic acid conjugates of serotonin (5-hydroxytryp-tamine), see Sect. 6.6.4 for withanamides, fatty acid amides of serotonin, see Sect. 8.I.2.I. 

A new simple amide, violyedoenamide (121), with five known compounds (palmitic, p-hydroxybenzoic, tra s-p-hydroxycinnamic, and butanedioc acids, and afzelin), was isolated from the lipophilic and alcoholic fractions of Viola yedoensis (Violaceae) (99). (See Fig. 12.)... 

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