Enantioselective Synthesis of Polyethers

描述（由申请人提供）：该项目将继续开发实用、灵活的策略，用于六至九元环醚的对映选择性合成，并将新策略应用于结构新颖和具有重要生物学意义的天然产物的全合成。在本研究过程中，将探索基于建立无环立体化学阵列并进行环闭合的环醚和环碳环的不对称构造的新合成技术。在下一个拨款期内，将完成短叶草毒素A的全部合成。sorangicin A、brevenal、半breven毒素B、硬藓素A、brianthein A和verillin的合成也将进行。这些天然产物的重要类似物也将被制备。一种新的1,1 '-二取代醚键的3组分组合物，一种新的不对称乙酸醛醇和一种抗乙醇酸醛醇将进一步开发和利用。二碘基Claisen重排将进一步发展为构建四元立体中心，并应用于花青素A和维林。将进行灯盏草毒素A、sorangicin A、灯盏草硬化素A、灯盏草素A和verillin的全合成。研究合成环醚和碳环的对映选择性新方法。

DESCRIPTION (provided by applicant): This program will continue to develop practical, flexible strategies for the enantioselective synthesis of six to nine membered ring ethers and apply the new strategies to the total synthesis of structurally novel and biologically important natural products. During the course of this investigation, new synthetic technologies will be explored for the asymmetric construction of cyclic ethers and carbocycles based on establishing acyclic stereochemical arrays followed by ring closure. During the next grant period the total synthesis of brevetoxin A will be completed. The synthesis of sorangicin A, brevenal, hemibrevetoxin B, sclerophytin A, brianthein A, and verillin will also be pursued. Important analogs of these natural products will also be prepared. A novel 3- component assembly of 1, 1'-disubstituted ether linkages, a new asymmetric acetate aldol, and an anti-glycolate aldol will be further developed and exploited. The dianioic Claisen rearrangement will be further developed for construction of quaternary stereogenic centers and applied to brianthein A and verillin. The total synthesis of brevetoxin A, sorangicin A, brevenal sclerophytin A, brianthein A and verillin will be carried out. New enantioselective methods for the synthesis of cyclic ethers and carbocycles will be investigated.