ASYMMETRIC SYNTHESIS OF BIOLOGICALLY IMPORTANT ALKALOIDS

我们建议进一步开发、改进和测试用于 一些杂环的立体选择性烷基化，α到氮 以优良的化学和化学方法提供生物碱和其他胺的体系 光学产生率。其中有几种方法是史无前例的，而且都负担得起 获得重要的化合物类别，因为它们的独特 结构特征和/或它们在化学和化学中的关键作用 生物化学。新的偶极稳定的阴离子前驱体将是 被研究为非环类潜在有用的合成工具 立体选择。 异吲哚的不对称α，α‘-二烷基化提供了 一类独特的具有C2对称性的手性2度胺。对.的使用 这些2度胺作为对映体选择性碱也将被考察。 因为它们在其他几个不对称过程中用作手性佐剂。我们 建议评价其他氨基恶唑类化合物作为手性佐剂，并 我们继续努力阐明不对称诱导的机制。 偶极稳定的阴离子体系。

We propose to further develop, refine, and test new methods for the stereoselective alkylation, alpha to nitrogen, of a number of heterocyclic systems affording alkaloids and other amines in excellent chemical and optical yields. Several of these methods are unprecedented, and all afford access to classes of compounds which are important because of their unique structural features and /or their pivotal role in chemistry and biochemistry. The new dipole-stabilized anion precursors will be investigated as potentially useful synthetic tools in acyclic stereoselection. The asymmetric alpha, alpha'-dialkylation of isoindoline affords access to a unique class of chiral 2 degree amines having C2 -symmetry. The use of these 2 degree amines as enantioselective bases will be examined, as well as their use as chiral adjuvants in several other asymmetric processes. We propose to evaluate other aminooxazolines as chiral adjuvants, and to continue our efforts to elucidate the mechanism of asymmetric induction in dipole-stabilized anion systems.