Fuses gallic acid

Pyrogallol—PyrogoUic acid—(OH), —126—is foimed when gallic acid q, v.) is heated to 200° (392° F.). It oiystallizes in white needles neutral iu reaction very soluble in water very bitter fuses at 115° (239° F.) boils st 210° (410° F.) poisonous. Its most vslusbis property... 

Needles from EtOHAq. M.p. 237°. Gives off I above 220°. Decomp, at 260°. Sol. EtOH,. Et 0. Almost insol. hot HgO. Fused with KOH—>-gallic acid. With PeClg in warm—> red col. 

Fig. 4 High-pressure fast gradient separation of natural phenolic antioxidants, (a) Ascentis Express CIS column with fused core 2.7 Jtm CIS particles with a thin porous outer shell (0.5 p.m), 30 X 3.0 mm I.D. at 1.5 ml/min, 53 MPa. (b) Acquity BEH Phenyl column with totally porous particles in 1.7 Jtm particles at 1.5 ml/min, 74 MPa, UV detection, 254 nm. Sample 1, gallic acid 2, protocatechine 3, esculine 4, chlorogenic acid 5, caffeine 6, epicatechine 7, vanilline S, rutine 9, sinapic acid 10, hesper-idine 11,4-hydroxycoumarine 12, morine 13, quercetine 14, 7-hydroxyflavone.

Ye et al. have determined catechin, rutin, ferulic acid, o-dihydroxybenzene, chlorogenic acid, caffeic acid, gallic acid, and protocatechuic acid in coffee by CE-AD [24]. The working electrode was a carbon disk electrode at an applied potential of -1-0.95 V (vs. SCE). Under the optimum conditions, the analytes can be well separated within 26 min in a 75-cm-long fused-silica capillary. The current response was linear over three orders of magnitude with detection limits ranging from 60 to 360ng/ml for all analytes. 

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