对于赋予吉姆诺辛-B绝对配置的三个挑战
Katsunori Tanaka1, Yasuhiro Itagaki, Masayuki Satake
1Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA.
Journal of the American Chemical Society
|June 30, 2005
概括
海洋毒素吉姆诺辛-B的绝对配置被确定为 (S) 在位置10和37. 这是通过克服衍生化的挑战和采用先进的循环二元化技术来实现的.
科学领域:
- 海洋天然产品 化学 化学
- 有机化学 有机化学
- 频谱学是一种光谱学.
背景情况:
- 吉姆诺辛-B是已知的最大的多海洋毒素.
- 确定复杂分子的绝对配置对于理解它们的生物活性至关重要.
- 之前的研究在分配吉姆诺辛-B的立体化学方面遇到了挑战.
研究的目的:
- 为了最终确定吉姆诺辛-B的绝对配置.
- 为了解决与这种复杂的海洋毒素配置分配相关的挑战.
主要方法:
- 在硬质阻碍基上引入一个p- ((meso-triphenylporphyrin) -cinnamate (TPPcinnamate) 组.
- 对金诺辛-B-TPPcinnamate衍生物的合规性分析.
- 循环二元化 (CD) 和光检测循环二元化 (FDCD) 谱学.
- 使用MMFF优化和DeVoe合振荡器方法进行计算分析.
主要成果:
- 在温和条件下,在C-10和C-37基位置上成功衍生了吉姆诺辛-B.
- 对bis-TPPcinnamate衍生物的实验CD和FDCD光谱显示出一个阳性激子对.
- 优化结构的理论CD计算与实验数据一致.
- 绝对配置被确定为 (S) - 10和 (S) - 37.
结论:
- 吉姆诺辛-B的绝对配置已经明确确定为 (S) - 10和 (S) - 37.
- 这项研究表明,氨酸激活子性对于确定大型复杂分子的绝对配置具有实用性.
- 这项工作为进一步研究健美素-B的生物活性和合成提供了基础.
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