Taurocholic acid

Taurocholic acid is one of the bile acids . The empirical formula is C ₂₆ H ₄₅ NO ₇ S.

Taurocholic acid
Are common
Traditional names	Taurocholic acid
Chem. formula	C₂₆H₄₅NO₇S
Rat formula	C 26 H 45 NO 7 S
Physical properties
Molar mass	515.7058 g / mol
Thermal properties
T. melt.	125 ° C
Classification
Reg. CAS number	81-24-3
Pubchem
Reg. EINECS number
Smiles
Inchi
Chebi
ChemSpider

It is found in the bile of many animals. It is quite difficult to obtain it in its pure form, because it is usually mixed with glycocholic acid; only in the bile of the dog and python there is no impurity of glycocholic acid.

To obtain taurocholic acid from dog bile, one proceeds as follows: bile is converted into sodium taurocholic acid, dissolved in water and precipitated with acetic-lead salt and ammonia . The filtered precipitate is mixed with alcohol and decomposed with sulfuric acid , the solution is concentrated to a very small volume and precipitated with a large excess of ether . The resulting syrupy precipitate with prolonged sedimentation passes into transparent, brilliant, taurocholic acid crystals floating in the air. Get taurocholic acid from dog bile in another way: bile is evaporated to dryness, extracted with alcohol and again evaporated; the resulting dry residue is dissolved in a small amount of absolute alcohol, and sodium taurocholic acid is precipitated from this solution with ether, which is dissolved in water and decomposed with acetic-lead salt and ammonia. The resulting precipitate was dissolved by boiling in absolute alcohol, precipitated with hydrogen sulfide , evaporated and purified with ether.

From bile of cattle, taurocholic acid is obtained as follows: bile is precipitated with medium acetic-lead salt, and the filtrate in parts with basic acetic-lead salt; in the first precipitation, glycocholic acid is obtained mainly, in the second, an increasingly pure taurochole-lead salt is gradually obtained. The precipitate of this salt is dissolved in hot alcohol, poured into water, the resulting precipitate is collected, dried, redissolved in alcohol and decomposed with sulfuric acid. After this, the solution is concentrated in a rarefied space; After a while, crystals of taurocholic acid precipitate from it.

Taurocholic acid is soluble in water and alcohol, less in ether. When the solution is evaporated in a water bath or when boiling with barite water, it splits into taurine and cholic acid . The same splitting occurs under the influence of acids, alkalis and putrefactive bacteria. Taurocholic acid has pronounced acidic properties and is a fairly powerful antiseptic. It is an excellent reagent for the quantification of proteins; although tannin and tungsten phosphoric acid are also sensitive, they sometimes degrade peptones and albuminoids , which is never the case with taurocholic acid. Taurocholic acid (already 0.2-0.5%) prevents the decay of meat infusion, stops alcohol and milk fermentation (0.25% is enough). Of the salts, sodium and potassium salts are known: NaC ₂₆ H ₄₄ NSO ₇ - crystalline, rotates the plane of polarization to the right, highly antiseptic; KC ₂₆ H ₄₄ NSO ₇ is also crystalline ^[1] .