Recent Advances in Polyphenol Research. Группа авторов
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and its bis‐2,4‐epi isomer 74 in 29% overall yield from 73α, respectively.
2.4 Conclusion
This chapter has reviewed an emerging class of oligomeric PAs possessing A‐type dual interflavan linkages, covering their structures, putative biosynthesis, and chemical synthesis. The research on this class of complex oligomers is still limited by the scarce availability of samples with high purity. For future progress, the role of organic synthesis is quite important, requiring the development of reliable synthetic methods, including (i) the flexible preparative methods of the flavan‐3‐ol monomeric constituents, and (2) facile means of constructing the [3.3.1]‐bicyclic skeleton with control of the stereo‐ and regiochemistry. The latter process needs to be reiterative, in dealing with the targets having multiple A‐type linkages. We hope this review will provide insights for further development and might serve as an invitation to researchers of various fields, attracting interest to this potentially exciting field.
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