P-Hydroxyhenzoic acid

Fig. 6 Comprehensive LC x LC separation of phenolic acids and flavones using parallel gradients in the first and in the second dimension, (a) Instrumental setup (h) parallel gradients in the first (D1) and in the second (D2) dimensions (c) contour plot and (d) 3-D presentations of 2-D chromatograms, UV detection at 280 nm. D2 pressure = 400 har. Compounds 1, esculine 2, 4-hydroxyphenylacetic acid 3, chlorogenic acid 4, gallic acid 5, protocatechuic acid 6, syringic acid 7, vanillic acid 8, salicylic acid 9, hesperidine 10, p-hydroxyhenzoic acid 11, sinapic acid 12, (-)-epicatechine 13, naringin 14, caffeic acid 15, ferulic acid 16, (-l-)-catechin 17, 4-hydroxycoumarin 18, p-coumaric acid 19, rutine 20, flavone 21, 7-hydroxyflavone 22, hesperetin 23, naringenin 24, luteolin 25, apigenin 26, quercetin 27, hiochanin A.

In the 1960s the Carborundum Company introduced the homopolymer of p-hydroxyhenzoic acid under the trade name Ekonol [35]. It is used in plasma coating. This wholly aromatic homopolyester is produced in practice by the self-ester exchange of the phenyl ester of p-hydroxyhenzoic add. 

Nakamura, Y, and Higuchi, T. (1978) Ester linkage of p-coumaric acid in bamboo lignin. II. Syntheses of coniferyl p-hydroxyhenzoate and coniferyl p-coumarate as possible precursors of aromatic acid esters in lignin. Cellul. Chem. Technol. 12(2), 199-208. 

Hydroxyhenzoic acid, isodecyl ester. See Isodecyl paraben 4-Hydroxybenzok acid, methyl ester. See Methylparaben 4-Hydroxybenzok acid, propyl ester p Hydroxybenzok acid, propyl ester. See Propylparaben... 

---