Bioinspired Synthesis of the Central Core of Halichonadin H: The Passerini Reaction in a Hypothetical Biosynthesis of Marine Natural ProductsWe are grateful for the financial support provided by a Grant-in-Aid for Scientific Research (C) (16K01916) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT).
Received: 30 January 2019
Accepted after revision: 08 February 2019
14 March 2019 (eFirst)
A pathway is proposed for the biosynthesis of the unique homodimeric terpene, halichonadin H. The proposed biosynthetic pathway involves two key Passerini reactions of eudesmane-type terpene isocyanides. The Passerini reaction of a model terpene isocyanide and formaldehyde afforded an α-hydroxy acetamide, which was further subjected to oxidation and a second Passerini reaction. This reaction sequence furnished an α-hydroxy malonamide connected with two identical terpene units which is the identical structural motif found in halichonadin H.
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For work related to ref. 3d, see: