Chemical Structure from Scientific Research

CgnB, CgnC and CgnE install two beta-hydroxylations and facilitate the two ring-closure reactions. CgnD cleaves the core scaffold off the leader peptide, which is subsequently methylated and carbamoylated. Crocagin B, the low abundance crocagin in extracts from the natural producer, appears to originate from oxidation before ring closure during the biosynthesis of 3a to yield 3b .

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