Lansai B is an indole alkaloid whose biosynthesis is not yet elucidated. However, utilizing nature’s tools enabled the stereoselective formation of this unique framework, first by providing the substituted tryptophan as starting material and later in the scaffold‐building step forming the pyrroloindole motif. For the latter the C3‐methyltransferase from Streptomyces griseoviridis (SgMT) is employed for the diastereoselective methylation. Investigating the scope of enzyme proved that introducing a bromide in 5‐position was ideal for the synthetic endeavor. With this, the stage was set for the synthesis of Lansai B introducing the prenyl‐group late via a Suzuki coupling.

中文翻译：

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Lansai B 的化学酶全合成


Lansai B 是一种吲哚生物碱，其生物合成尚未阐明。然而，利用大自然的工具实现了这种独特框架的立体选择性形成，首先提供取代的色氨酸作为起始材料，然后在形成吡咯吲哚基序的支架构建步骤中。对于后者，来自灰病毒链霉菌 （SgMT） 的 C3-甲基转移酶用于非对映选择性甲基化。调查酶的范围证明，在 5 位引入溴化物是合成工作的理想选择。这样，为 Lansai B 的合成奠定了基础，通过 Suzuki 偶联引入异戊二烯基。