Linden

Tetraphlorethol C is a phlorethol-type phlorotannin found in the brown alga Ascophyllum nodosum.^[1] chemically, it is a tetramer of 1,2,3,5-Tetrahydroxybenzene

References

^ Effects of phlorotannins from Ascophyllum nodosum (brown seaweed) on in vitro ruminal digestion of mixed forage or barley grain. Y. Wang, Z. Xu, S.J. Bach and T.A. McAllister, Animal Feed Science and Technology, 14 August 2008, Volume 145, Issues 1–4, Pages 375–395, doi:10.1016/j.anifeedsci.2007.03.013

Types of phlorotannins (tannins in brown algae)
Monomer	Phloroglucinol
Fucols	Difucol Trifucol Tetrafucol A Tetrafucol B cis-Pentafucol A
Phlorethols	Diphlorethol and diphlorethol A Triphloroethol A Tetraphlorethol A, B, C and E Pentaphlorethol-B Hexaphlorethol-A
Fucophlorethols	Fucophlorethol A and B Fucodiphlorethol A, D and G Fucotriphlorethol-B, G and H Fucotetraphlorethol-B, J and K Fucopentaphlorethol-E Bisfucotriphlorethol-A Bisfucotetraphlorethol-A Bisfucopentaphlorethol-A and B Bisfucoheptaphlorethol-A Difucophlorethol-A Difucofucotriphlorethol-A and B Difucofucotetraphlorethol-A Terfucopentaphlorethol-A Terfucohexaphlorethol-A and B Terfucoheptaphlorethol-A
Fuhalols	Bifuhalol Trifuhalol A Tetrafuhalol A
Isofuhalols	Tetraisofuhalol
Eckols	Dieckol Eckol Eckstolonol Phlorofucofuroeckol A and B 2-Phloroeckol 3-Phloroeckol 6,6'-Bieckol 7-Phloroeckol 8,4"'-Dieckol 8,8′-Bieckol
Halogenated phlorotannins	Bromotriphlorethol A1