ABSTRACT

Icetexanes are natural diterpenes exhibit a series of interesting biological activities, such as antibacterial, antifungal, anti-cancer and anti-inflammatory activities, which has become a hot research area for biologists and chemists. In which the taxamairins represent a subclass of highly unsaturated icetexanes. However, it’s inefficient and illegal to obtain taxamairins from nature source which strongly limits the further investigation. The reported organic total synthesis methods to obtain taxamairins have drawbacks for large-scale synthesis, including long synthetic routes, low yields, infeasible key steps, expensive reagents, etc.

In this study, the natural products TaxA and TaxB were semi-synthesized starting from the commercially available natural product carnosic acid and going through 6 and 7 steps respectively with a total yield of 12% and 21% in gram scales in 7 days. Furthermore, 17 taxamairins analogous were designed and developed via hydroxylation reaction, oxidation reaction, esterification reaction, amidation reaction and coupling reaction. This method can provide a reliable way for large-scale preparation of taxamairins.

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