Designed whole-cell-catalysis-assisted synthesis of 9,11-secosterols.

A method for the synthesis of 9,11-secosteroids starting from the natural corticosteroid cortisol is described. There are two key steps in this approach, combining chemistry and synthetic biology. Stereo- and regioselective hydroxylation at C9 (steroid numbering) is carried out using whole-cell biocatalysis, followed by the chemical cleavage of the C-C bond of the vicinal diol. The two-step method features mild reaction conditions and completely excludes the use of toxic oxidants.