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An unknown bile acid was found by gas-liquid chromatography in the serum of patients who were administered ursodeoxycholic acid for the treatment of cholesterol gallstones. Identification of the chemical structure of the unknown bile acid was performed by the use of gas-liquid chromatography-mass spectrometry. Mass spectrum analysis of the methyl ester trimethylsilyl ether of the bile acid showed explicitly that this is dihydroxy-5 beta-cholanoic acid, since peaks at m/e 460 and 370 characteristic of methyl ester trimethylsilyl ether of dihydroxy bile acid were clearly exhibited. Sites of the two hydroxyl groups on the steroid nucleus were determined to be at the 3- and 7-positions by conversion of the bile acid to the corresponding dioxo-cholanoic acid and by comparison of the gas-liquid chromatographic behavior with those of authentic dioxo bile acids. Four authentic 3,7-dihydroxy-5 beta-cholan-24-oic acids were chemically synthesized and retention times and mass spectra of their methyl ester trimethylsilyl ether derivatives compared precisely with that of the unknown bile acid. The results indicate that the unknown bile acid is 3 beta, 7 beta-dihydroxy-5 beta-cholan-24-oic acid. Preliminary experiments suggest that 3 beta, 7 beta-dihydroxy-5 beta-cholan-24-oic acid is absent as amino acid-conjugated forms in serum. It is also suggested that the bile acid is excreted into urine but not into bile.
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
January 1986,
Steroids,
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
November 1993,
Nihon Shokakibyo Gakkai zasshi = The Japanese journal of gastro-enterology,
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
August 1992,
Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan,
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
July 1990,
Steroids,
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
January 1988,
Hepatology (Baltimore, Md.),
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
June 1984,
Journal of medicinal chemistry,
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
April 1988,
Journal of medicinal chemistry,
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
June 1982,
Steroids,
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
February 1985,
Journal of medicinal chemistry,
M Maeda, and
H Ohama, and
H Takeda, and
M Yabe, and
M Nambu, and
T Namihisa
March 2003,
Journal of lipid research,
