Synthesis of Heterocyclic Natural Products

在有机化学和高分子化学计划的支持下，宾夕法尼亚州立大学大学园区化学系的Steven M.Weinreb教授正在进行几种具有生物学意义的复杂自然分子的立体选择性全合成，并辅之以开发新的实用有机合成方法。以Weinreb教授的N-亚磺酰二烯亲和体Diels-Alder方法为关键步骤，研究了一种全合成肝毒性生物碱圆柱型精浆蛋白的方法。还将合成几种结构独特的查特林/赛可拉明类多环海洋苔藓虫生物碱。最近分离的新型五环吲哚生物碱曲诺卡品的全合成将利用1-羟基吲哚的独特化学。新的化学合成方法将被研究，包括一种简单的替代Eschenmoser偶联反应来制备乙烯基酰胺和氨基甲酸酯的方法，以及使用N-亚磺酰基化合物作为形成糖苷和N-糖苷键的试剂。构建具有良好的生物活性或药理活性的经常复杂的分子需要开发新的复杂的有机分子的合成方法。随着新方法的发展，它们最终必须通过对实际合成问题的应用来测试和证明是有效的。这种测试还提供了有机合成思维过程和实践方面的培训，这对学生的教育发展至关重要，这些学生将成为下一代执业有机化学家。在有机化学和高分子化学计划的支持下，宾夕法尼亚州立大学大学园区化学系的Steven M.Weinreb教授正在探索开发新的实用有机合成方法，并将它们应用于几种具有生物意义的复杂天然分子的全合成。

With the support of the Organic and Macromolecular Chemistry Program, Professor Steven M. Weinreb, of the Department of Chemistry at Pennsylvania State University, University Park, is carrying out the stereoselective total synthesis of several complex naturally-occurring molecules of biological significance, complemented by the development of new and practical methods for organic synthesis. An approach to the total synthesis of the hepatotoxic alkaloid cylindrospermopsin uses as a pivotal step Professor Weinreb's N-sulfinyl dienophile Diels-Alder methodology. Several structurally unique polycyclic marine bryozoan alkaloids of the chartelline/securamine class will also be synthesized. The total synthesis of the recently isolated novel pentacyclic indole alkaloid tronocarpine will utilize the unique chemistry of 1-hydroxyindoles. New methods of chemical synthesis will be investigated, including a simple alternative to the Eschenmoser coupling reaction for preparing vinylogous amides and carbamates, and the use of N-sulfinyl compounds as reagents for the formation of glycosidic and N-glycosidic bonds.Construction of the often-complex molecules which display desirable biological or pharmaceutical activity requires the development of new and sophisticated methods for the synthesis of organic molecules. As new methods are developed, they ultimately must be tested and proven effective through their application to real synthetic problems. Such testing also provides training in the thought processes and practice of organic synthesis, vital to the educational development of students who will become the next generation of practicing organic chemists. With the support of the Organic and Macromolecular Chemistry Program, Professor Steven M. Weinreb, of the Department of Chemistry at Pennsylvania State University, University Park, is exploring the development of new and practical methods for organic synthesis and applying them to the total synthesis of several complex naturally-occurring molecules of biological significance.