Synthesis of steroidal quinones and hydroquinones from bile acids by Barton radical decarboxylation and benzoquinone addition. Studies on their cytotoxic and antifungal activities

Twelve new hydroquinones and quinones (4a–c to 7a–c) derived from free or peracetylated bile acids were prepared by a Barton decarboxylation reaction, with subsequent trapping of the resulting free radical by benzoquinone. All new compounds were completely characterized by 2D NMR techniques and screened for antifungal and cytotoxic activity. One of the new hydroquinones (7b) showed promising results against the human pancreatic ductal carcinoma cell line PANC1, with similar cytotoxic activity as the commercial chemotherapy drug doxorubicin.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Twelve new quinones and hydroquinones were synthesized from bile acids. ► The key step of the synthesis was a Barton decarboxylation reaction. ► The radicals derived from Barton esters were quenched with benzoquinone. ► The antifungal and cytotoxic activities of the compounds were tested. ► One of the new compounds was highly active against a pancreatic carcinoma cell line.