Application of palladium-catalyzed carboxyl anhydride-boronic acid cross coupling in the synthesis of novel bile acids analogs with modified side chains

• Cross coupling of bile acids and 4-methoxycarbonyl phenylboronic was achieved.
• 24-(4′-Methoxycarbonylphenyl)-5β-cholan-24-ones were obtained.
• Wolff–Kishner reduction of the obtained compounds led to new bile acids analogs.
• X-ray and NMR allowed the unambiguous characterization.

Palladium-catalyzed cross coupling of 4-methoxycarbonyl phenyboronic acid with acetylated bile acids in which the carboxyl functions was activated by formation of a mixed anhydride with pivalic anhydride afforded the cross coupled compounds, which were converted in novel side chain modified bile acids by one pot carbonyl reduction/removal of the protecting acetyl groups by Wolff–Kishner reduction. Unambiguous assignments of the NMR signals and crystal characterization of the heretofore unknown compounds are provided.

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