Alkyl ferulates

Bennett DJ, Kirby GW (1968) Constitution and biosynthesis of capsaicin. J Chem Soc (C) 442-446 Bernards MA, Lewis NG (1992) Alkyl ferulates in wound healing potato tubers. Phytochemistry 31 3409-3412... 

HHT activity was not detectable in intact potato tuber tissue but was induced upon wounding after a lag period of three days (Fig.2). The time course of induction of HHT was therefore comparable with the kinetics of accumulation of alkyl ferulates [3] and of deposition of the aliphatic components of suberin [1]. HHT activity being restricted to the outermost cell layers of the wound-healing tuber discs, the development of HHT activity was both temporally and spatially coincident with the suberization process. The... 

Bernards MA. and Lewis NG. Alkyl ferulates in wound healing potato tubers. Phytochemistry 1992 31, 3409-3412. 

Li et al. (2009) have studied the synthesis of alkyl ferulates under microwave inadiatioa They observed the reactions time ranged from 3-5 min, which was much shorter than the traditional synthetic methods, as well as the alkyl ferulates were obtained in higher yields. It was the first time, when they have reported an efficient microwave-assisted esterification of ferulic acid with alcohols. 

Figure 2.8 Summary of behavior of phenolic acid esters and free forms in the GIT and the liver. 5-O-CQA, 5-O-caffeoylquinic acid 5-O-FAAF, 5-O-feruloyl-L-arabinofura-nose C, conjugate (sulfate, glucuronide or methyl) CA, caffeic acid FA, ferulic acid FA-FA, dimer of ferulic acid FA-oligosac., ferulic acid esterified to an oligosaccharide FA-Xy, ferulic acid esterified to xylan R, alkyl group.

The presence of methylation, alkylation, or ester groups makes flavonoids more lipid-like in nature (Fig. 11.4). In many cases, aglycones and glycosides are additionally substituted and occur as esters (acetate, malonate, butyrate, cin-namate, p-coumarate, ferulate, etc.) or ethers. In contrast to water-soluble glycosides that are usually accumulated in the vacuole, flavonoid esters and ethers usually are associated with waxes or found in the cytoplasm. 

Long chain alkyl esters of ferulic acid are common constituents in the family. From the seeds of Hyoscyamus niger even a diester, 1,24-tetracosanediol diferulate could be isolated (Ma et al. 2002). Solanum tuberosum started to accumulate long chain alkyl (mono)esters three to seven days after wound treatment. The alcohol components ranged from hexadecyl (Cj Hjj) to octacosyl (C gHj,) all even numbers plus two esters of odd chain length alkanols [nonadecyl (Cj Hj ), heneicosyl (C jH j)]. The major metabolites were represented by hexadecyl and octadecyl ferulates. The authors suppose that the formation of all these ferulates is temporally and spatially correlated with suberin formation since they were restricted to the wound periderm (Bernards and Lewis 1992). For a coherent account of suberin chemistry interested readers are directed to a review on the macromolecular aromatic domain in suberized tissues (Bernards and Lewis 1998). 

Silylated alkyl phenols, alkyl phenyl ethoxylate Phenols, aromatic acids, eg pentachlorophenol, bisphenol, phthalic acid, trimesic acid, p-hydroxy-benzoic acid, vanilic acid, syringic acid, p-coumaric acid, ferulic acid... 

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