Linkages, unnatural amide

The enzymatic system that promotes the amide linkage between L-histamine and isovaleric acid in D. sphaerica is not specific, so aberrant or unnatural alkaloids (derivatives produced in the absence of natural precursors) can be produced. Different aberrant alkaloids were produced in labeled studies one could infer that this system is suitable to prepare biologically active natural products that are difficult to synthesize [AA A6]. 

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