Conversion of cholic acid to methyl 3alpha-carbethoxy-12alpha-acetoxy-6-oxo-5beta-chol-7-en-24-oate.
A new and efficient method for preparation of a 7-en-6-one derivative of cholic acid is described. Acetylation of the known methyl 3alpha-carbethoxy-12alpha-hydroxy-7-oxo-5beta-cholan-24-oate (3) at 12 position and reduction of its 7-oxo group yield the 12alpha-acetoxy-7alpha-hydroxy derivative 5. Dehydration of the 7alpha-hydroxy group in 5 followed by allylic oxidation provide methyl 3alpha-carbethoxy-12alpha-acetoxy-6-oxo-5beta-chol-7-en-24-oate (7) in good yield.
Masterson
Sean P
SP
Department of Chemistry, Indiana University Southeast, 4201 Grant Line Road, New Albany, IN 47150, USA.
Miller
Thomas A
TA
Nassim
Bahman E
BE
D002625:Chemistry, Organic / Q000379:methods; D019826:Cholic Acid / Q000737:chemistry / Q000378:metabolism*; D002793:Cholic Acids / Q000737:chemistry / Q000378:metabolism*; D013057:Spectrum Analysis; D013237:Stereoisomerism; D014961:X-Ray Diffraction
D002793:Cholic Acids; C479599:methyl 3-carbethoxy-12-acetoxy-6-oxochol-7-en-24-oate; D019826:Cholic Acid