Table 5.

Structures and activity of tannins and their esters with n-alkanol chain lengths against hyaluronidase.

Structure	Compound	$R_1$	$R_2$	$R_3$	$R_4$	${IC}_{50}$ (µM)	References
	Gallic acid	H				>1000	Barla et al.53
	Methyl gallate	O${\mathrm{CH}}_3$				>1000
	Ethyl gallate	O${\mathrm{CH}}_2{\mathrm{CH}}_3$				>1000
	Propyl gallate	${{O(CH}_2)}_2{CH}_3$				>1000
	Butyl gallate	${{O(CH}_2)}_3{CH}_3$				>1000
	Hexyl gallate	${{O(CH}_2)}_5{CH}_3$				253
	Heptyl gallate	${{O(CH}_2)}_6{CH}_3$				112
	Octyl gallate	${{O(CH}_2)}_7{CH}_3$				106
	Nonyl gallate	${{O(CH}_2)}_8{CH}_3$				167
	Decyl gallate	${{O(CH}_2)}_9{CH}_3$				580
	Dodecyl gallate	${{O(CH}_2)}_{11}{CH}_3$				>1000
	Octyl 3-hydroxybenzoate	OH	H	H		>1000
	Octyl 4-hydroxybenzoate	H	OH	H		>1000
	Octyl 3,4-dihydroxybenzoate	OH	OH	H		902
	Octyl 3,5-dihydroxybenzoate	OH	H	OH		113
	Pedunculagin					1.51	Tokeshi et al.54
	Tellimagrandin I	H	OH	G		0.9	Sugimoto et al.52
	Tellimagrandin II	OG	H	G		0.58
	Heterophylliin A	H	OG	H		0.89
	1,3-Di-O-galloyl-4,6-hexahydroxydiphenoyl-β-D-glucose	OG	H	H		0.74
	1,2,4-Tri-O-galloyl-β-D-glucose	G	H	G	H	1.57
	1,2,3,6-Tetra-O-galloyl-β-D-glucose	G	G	H	G	0.35
	1,2,4,6-Tetra-O-galloyl-β-D-glucose	G	H	G	G	0.68
	1,2,3,4,6-Penta-O-galloyl-β-D-glucose	G	G	G	G	0.55
	Ellagic acid					4.66
	Gallic acid					5.00
	Agrimoniin					2.65
	Galloyl group (G)
Phloroglucinol
Phloroglucinol tetramer
Phlorofucofuroeckol A
Dieckol
8,8′-Bieckol