Chenodeoxycholic acid

Therapeutic Function Solubilizer for cholesterol gallstones Chemical Name 3,7-Dihydroxycholan-24-oic acid Common Name Chenodeoxycholic acid chenic acid Structural Formula ... 

To 1,400 ml of an approximately 50% water/triglycol solution of the potassium salt of cheno-deoxycholic acid, obtained by the Wolff-Kishner reduction (using hydrazine hydrate and potassium hydroxide) from 50 g of 7-acetyl-12-ketochenodeoxycholic acid, 220 ml of dilute hydrochloric acid is added to bring the pH to 2. The solution is stirred and the crude cheno-deoxycholic acid precipitates. The precipitate is recovered and dried to constant weight at about 60°C. About 36 g of the crude chenodeoxycholic acid, melting in the range of 126°-129°C, is obtained. 

Chenodeoxycholic acid Deoxycholic acid Lithocholic acid Ursodeoxycholic acid Muricholic acid... 

C24H4q05 81 -25-4) see Chenodeoxycholic acid Dehydrocholic acid choline chloride... 

The primary bile acids are synthesized in the liver from cholesterol. These are cholic acid (found in the largest amount) and chenodeoxycholic acid (Figure 26-7). 

The answer is d, (Hardman, pp 934-935.) Chenodeoxycholic acid (chenodiol) and ursodiol have proved to he effective in some patients with cholesterol gallstones. Lovastatin lowers blood cholesterol levels but has no effect on gallstones. Methyl tertiary butyl ether and a new agent, monoctanoin, are infused directly into the common duct and will dissolve gallstones. 

The broad-spectrum antibiotic chlorotetracycline and the aminoglycoside antibiotic kanamycin are observed to lower the cholesterol levels by forming salts with bile acids (e.g.. cholic acid, deoxycholic acid and chenodeoxycholic acid) in the intestinal canal,... 

Figure 4.14 Structures of cholic and chenodeoxycholic acids which are the acids that form the bile salt The asterisk indicates the position at which an ester bond is formed with taurine or glycine so that bile salts are taurocholate, chenodeoxytaurocholate, gly-cocholate, and glycochenodeoxycholate are formed. The structure of taurine is H2NCH2CH2SO3 and glycine is H2NCH2COOH.

Figure 1.1 illustrates a condensed version of the classical pathway of bile-acid synthesis, a series of 12 enzymatic reactions that convert cholesterol, which is insoluble, into BAs, which are water soluble. The cholesterol is first converted to 7 alpha-hydroxy cholesterol, followed by the series of enzymatic transformations, eventually producing cholic and chenodeoxycholic acids (not all steps shown). The rate-limiting enzyme in this pathway is cholesterol 7 alpha-hydroxylase (CYP 7A1), which originates from microsomal cytochrome P-450 enzymes, expressed only in the liver hepatocytes. 

CA, cholic acid CDCA, chenodeoxycholic acid DCA, deoxycholic acid LCA, lithocholic acid. Tumor end-point also ... 

Figure 5.2 Therapeutic interventions for decreasing colorectal mucosal bile acid exposure as a CRC chemoprevention strategy. 1) Lifestyle modifications including reduction in dietary animal fat and increased fibre intake may, at least partly, be explained by reduction in luminal primary (cholic acid [CA] and chenodeoxycholic acid [CDCA]) and secondary (deoxycholic acid [DCA] and lithocholic acid [LCA]) bile acids. 2) Reduction of secondary bile acids, which are believed to have pro-carcinogenic activity could be obtained by decreased bacterial conversion from primary bile acids. 3) Alternatively, bile acids could be sequestered by chemical binding agents, e.g. aluminium hydroxide (Al(OH)3) or probiotic bacteria. 4) Exogenous ursodeoxycholic acid (UDCA) can reduce the luminal proportion of secondary bile acids and also has direct anti-neoplastic activity on colonocytes in vitro.

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