INTRAMOLECULAR PYRONE/PYRIDONE (4+4) PHOTOCYCLOADDITIONS

分子内吡喃酮/吡啶酮 (4 4) 光环负载添加剂

• 批准号: 3304596
• 负责人: Scott McNeill Sieburth
• 金额: $ 11.41万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-01-01 至 1993-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3304596
• 关键词: antineoplastic antibiotics; biological products; chemical models; chemical reaction; chemical structure function; chemical synthesis; cyclization; cyclopentane; photochemistry; pyrones

The photochemical [4+4] dimerization of 2-pyrones and 2-pyridones is a potentially powerful method for construction of highly functionalized cyclooctanes. This reaction assembles two achiral, readily prepared, aromatic molecules into a 1,5-cyclooctadiene with four stereogenic centers and a terpene skeleton. An unprecedented intramolecular version of ths reaction would allow this transformation to be harnessed for the synthesis of complex, eight- membered ring natural products, many of which are associated with important biological activity (e.g., antitumor, antibiotic, etc.). In a preliminary study (1), a solution of a bis-pyridone with a three atom tether was irradiated. Only one major product, resulting from a [4+4] cyclization (greater than 80% yield, 100% conversion), was observed, indicating that the alcohol on the tether had strongly influenced the formation of four new stereogenic centers. The initial goal of this project is to explore the scope of this untested intramolecular reaction, emphasizing features which are important for synthetic applications such as tether length and stereoinduction. A study of the chemistry of the [4+4] product, in the context of models and total synthesis, will form the second stage of the investigation.

2-吡咯和2-吡啶酮的光化学[4+4]是一个 高度功能化的潜在强大方法 环谷。 该反应组装了两个易于准备的精神 芳族分子进入1,5个循环二二烯，具有四个立体源性 中心和萜烯骨骼。 史无前例的分子内版本的反应将允许这样做 用于合成复杂的转换，八 成员环天然产品，其中许多与 重要的生物学活性（例如抗肿瘤，抗生素等）。在 初步研究（1），三个原子的双吡啶酮的溶液 系绳被照射。 仅由[4+4]产生的主要产品 观察到环化（大于80％的产率，100％转化率）， 表明系绳上的酒精对 形成了四个新的立体源中心。 最初的目标 项目将探索未经测试的分子内的范围 反应，强调对合成很重要的特征 绳索长度和立体诱导等应用。 一项研究 [4+4]产品的化学性质，在模型和总和 合成将构成调查的第二阶段。