The Cover Feature shows a 4 steps short‐cut bio‐inspired synthetic tactic for the synthesis of the fused tricyclic guanidinic core of complex polycyclic crambescidine and batzelladine metabolites isolated from marine sponges of the orders Poecilosclerida and Axinellida. The synthetic strategy mirrors Robinson–Schöepf tropinone biomimetic synthesis together with the biomechanistic analysis of the isolated marine metabolites. The application of this strategy led to two unnatural diastereoisomers of merobatzelladine B, an anti‐infective tricyclic guanidine alkaloid, isolated from the marine sponge Monanchora sp. More information can be found in the Full Paper by A. Al‐Mourabit et al.

中文翻译：

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封面人物：Crambescidins和Batzelladines海洋生物碱的三环鸟嘌呤基序的捷径生物启发合成（Eur。J. Org。Chem。35/2020）

封面功能展示了一种4步生物合成的捷径，用于合成复杂多环crambescidine和batzelladine代谢物的稠合三环胍基核，该代谢物是从Poecilosclerida和Axinellida的海洋海绵中分离得到的。合成策略反映了Robinson-Schöepf肌钙蛋白的仿生合成以及对孤立的海洋代谢物的生物力学分析。该策略的应用导致了从海洋海绵Monanchora  sp。分离得到的两种非自然非对映异构体的merobatzelladine B，一种抗感染的三环胍生物碱。可以在A. Al-Mourabit等人的论文全文中找到更多信息。