Polyketides,a large class of secondary metabolites,have been of long-standing interest to the synthetic community due to their intriguing biological activities and structural versatility and complexity.A typical struc...Polyketides,a large class of secondary metabolites,have been of long-standing interest to the synthetic community due to their intriguing biological activities and structural versatility and complexity.A typical structural unit of various natural products,polypropionate,has prompted enormous efforts in the development of novel synthetic methods and strategies in the past five decades.In this study,a non-aldol-type approach based on double hydroboration of allenes has been developed to provide a powerful method for the stereodivergent construction of various polyol stereotriads and stereotetrads that are amenable for synthesizing polypropionates.The stereochemical control is possibly attributable to the boronate complex that aligned itself as a rigid conformation for the second stereoselective hydroboration reaction by suppressing the barotropic rearrangement of allylborane intermediates.The feasibility of preparing the key polypropionate motif facilitates the efficient synthesis of(-)-pironetin,a potentα-tubulin inhibitor halting the cell cycle at M phase.展开更多
基金support obtained from the Chinese Academy of Sciences(QYZDY-SSWSLH026 and XDB20020000)and the Drug Innovation Major Project(2018ZX09711001-005)is highly appreciated.The authors thank Zuming Lin for assisting with the experiments and Dr.Xiaoli Bao(SJTU)and Jie Sun(SIOC)for performing the X-ray analysis.
文摘Polyketides,a large class of secondary metabolites,have been of long-standing interest to the synthetic community due to their intriguing biological activities and structural versatility and complexity.A typical structural unit of various natural products,polypropionate,has prompted enormous efforts in the development of novel synthetic methods and strategies in the past five decades.In this study,a non-aldol-type approach based on double hydroboration of allenes has been developed to provide a powerful method for the stereodivergent construction of various polyol stereotriads and stereotetrads that are amenable for synthesizing polypropionates.The stereochemical control is possibly attributable to the boronate complex that aligned itself as a rigid conformation for the second stereoselective hydroboration reaction by suppressing the barotropic rearrangement of allylborane intermediates.The feasibility of preparing the key polypropionate motif facilitates the efficient synthesis of(-)-pironetin,a potentα-tubulin inhibitor halting the cell cycle at M phase.
