权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

SYNTHESIS VIA 4-PYRONES AND RELATED SYSTEMS

通过 4-吡喃酮和相关系统合成

基本信息

批准号：
2734667
负责人：
FREDERICK G WEST
金额：
$ 16.48万
依托单位：
UNIVERSITY OF UTAH
依托单位国家：
美国
项目类别：
财政年份：
1991
资助国家：
美国
起止时间：
1991-07-01 至 2000-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/2734667
关键词：
chemical addition chemical synthesis cyclization paclitaxel photochemistry pyrones

项目摘要

The original goal of this grant was the development of new methodology in the area of synthetic organic chemistry, based upon novel photochemistry of 4-pyrones. This chemistry allows for the rapid construction of complex, polycyclic structures, corresponding in many cases to biomedically important natural products, from simple, readily available precursors. In the renewal, a variety of new directions are presented, along with further exploration of the issues covered during the current grant period. An important focus in this application is the development of stereoselective versions of the reactions at hand. As many as five new chiral centers are created from achiral precursors. Thus, methods for forming these centers with good control of absolute stereochemistry are critical to fully exploit this chemistry. In particular, the use of Lewis acids to control the torquoselectivity of the Nazarov electrocyclization reaction will be examined. Methodology already developed or under current development will be applied to the synthesis of two challenging natural product targets. The intramolecular crossed [4+4]-photocycloaddition chemistry of 2-pyrones will be used in a synthesis of 7,8-epoxy-4-basmen-6-one. Cyclization/fragmentation approaches, using either 4-pyrone photochemistry or the Nazarov reaction, will be applied to taxinine. Long term goals include the eventual application of this methodology to taxol and related analogues.

这笔赠款的最初目标是开发新的方法在合成有机化学领域，基于新颖的 4-吡喃酮的光化学这种化学反应可以让复杂的多环结构的构建，对应于许多从简单的、容易的，到生物医学上重要的天然产物，可用的前体。在更新中，各种新的方向被提出，沿着进一步探讨本次赠款所涉问题期本申请的一个重要焦点是开发立体选择性的反应。多达五个新的手性中心由非手性前体产生。因此，形成这些具有良好的绝对立体化学控制的中心是这是充分利用这种化学物质的关键特别是使用刘易斯酸来控制Nazarov 将检查电环化反应。已经制定或正在制定的方法将应用于两个具有挑战性的天然产物目标的合成。的 2-吡喃酮分子内交叉[4+4]-光环加成化学将用于7，8-环氧-4-巴斯曼-6-酮的合成。环化/片段化方法，使用4-吡喃酮光化学或Nazarov反应，将应用于紫杉碱。长期目标包括最终将该方法应用于紫杉醇及其类似物。