Methanol → 3alpha-Hydroxy-7-oxo-5beta-cholan-24-oic acid methyl ester

Participants

Reaction Steps

Step 1 is the reaction of 3α-hydroxy-7-keto-5β-cholan-24-oic acid (KLCA) with CH3OH and H2SO4 to form 3α-hydroxy-7-keto-5β-cholan-24-oic acid methyl ester (1). In one embodiment of step 1, the reaction mixture is heated for about 3 hours and the pH of the reaction mixture is adjusted with an aqueous basic solution to a pH-value of about 6.5 to about 8.0. In one embodiment, the isolation of 3α-hydroxy-7-keto-5β-cholan-24-oic acid methyl ester (1) further comprises treatment with activated carbon. In one embodiment, the isolation of 3α-hydroxy-7-keto-5β-cholan-24-oic acid methyl ester (1) does not further comprise treatment with activated carbon. In one embodiment, isolation of 3α-hydroxy-7-keto-5β-cholan-24-oic acid methyl ester (1) without the treatment with activated carbon affords a higher yield. In one embodiment, reacting 3α-hydroxy-7-keto-5β-cholan-24-oic acid (1) with CH3OH and H2SO4 is carried out in methanol. In one embodiment, the basic solution is an aqueous NaOH solution. In one embodiment, the pH-value is about 7.0 to about 7.5.

Provenance & Evidence