Neuroactive metabolites from the bark of Galbulimima belgraveana occur in variable distributions among trees and are not easily accessible through chemical synthesis because of elaborate bond networks and dense stereochemistry. Previous syntheses of complex congeners such as himgaline have relied on iterative, stepwise installation of multiple methine stereocenters. We decreased the synthetic burden of himgaline chemical space to nearly one-third of the prior best (7 to 9 versus 19 to 31 steps) by cross-coupling high fraction aromatic building blocks (high F sp 2) followed by complete, stereoselective reduction to high fraction sp 3 products (high F sp 3). This short entry into Galbulimima alkaloid space should facilitate extensive chemical exploration and biological interrogation.

中文翻译：

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通过交叉偶联和完全还原简明合成 GB22、GB13 和 himgaline

来自树皮的神经活性代谢物贝氏银杏发生在树木之间的可变分布，并且由于复杂的键网络和密集的立体化学而不易通过化学合成获得。以前合成复杂同系物（如喜加碱）依赖于多个次甲基立体中心的迭代、逐步安装。我们通过交叉偶联高分数芳香结构单元（高 Fsp2) 随后完全立体选择性还原为高分数 sp3个产品（高Fsp3). 这个简短的进入加布利马生物碱空间应有助于广泛的化学探索和生物审讯。