Tannic acid (C09-1069-465)

Slight special smell, strong astringency, dark color in exposed light and air. Soluble in water, soluble in ethanol, acetone and glycerol, almost insoluble in ether, benzene, chloroform and petroleum ether. Slight special smell, with strong astringency.Light yellow amorphous powder or loose glossy scaly or spongy solid, most of them decompose into pyrogallic acid and carbon dioxide at 210-215 ℃. 1G in 0.35ml water and 1ml hot glycerin. Odorless, flammable. When it comes to albumin, starch, gelatin and many alkaloids and metal salts, it will precipitate. When it comes to iron salts, it will also produce black or precipitate. The spontaneous combustion point was 526.6 ℃, and the median lethal dose (rabbit, oral) was 5.0 g / kg.Tannin is not a single compound, and its chemical composition is complex① Condensed tannin is a kind of flavanol. The 2-position of flavanol in the molecule combines with catechol or pyrogallol through carbon carbon bond.② Hydrolyzable tannin, with ester bond in molecule, is gallate of glucose. The latter is commonly used tannin. The tannin obtained from gallnut of China contains about 12% glucose, and the tannin obtained from gallnut of Turkey contains about 16.5% glucose.Precipitation and gravimetric determination of be, Al, GA, in, Nb, Ta and Zr. Determination of copper, iron, vanadium, cerium and cobalt. It is a precipitant of protein and alkaloid. External indicator for titration of lead with ammonium molybdate. Dyes, mordants. Specification: ACS MDL Number: MFCD00066397 Molecular Formula: C76H52O46 Molecular Weight: 1701.2 EC Number: 215-753-2 PubChem CID: 16129778 Isomeric SMILES: C1=C(C=C(C(=C1O)O)O)C(=O)OC2=CC(=CC(=C2O)O)C(=O)OC[C@@H]3[C@H]([C@@H]([C@H]([C@@H](O3)OC(=O)C4=CC(=C(C(=C4)OC(=O)C5=CC(=C(C(=C5)O)O)O)O)O)OC(=O)C6=CC(=C(C(=C6)OC(=O)C7=CC(=C(C(=C7)O)O)O)O)O)OC(=O)C8=CC(=C(C(=C8)OC(=O)C9=CC(=C(C(=C9)O)O)O)O)O)OC(=O)C1=CC(=C(C(=C1)OC(=O)C1=CC(=C(C(=C1)O)O)O)O)O Beilstein Registry Number: 8186396 Related Documents: https://ald-pub-files.oss-cn-shanghai.aliyuncs.com/aladdinsci/pdp/sds/1/T308008-SCI_34a8f2e265a732d35dfdb93386342e6a.pdf