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4-(Dimethylamino)pyridine -Oxide-Catalyzed Macrolactamization Using 2-Methyl-6-nitrobenzoic Anhydride in the Synthesis of the Depsipeptidic Analogue of FE399. | LitMetric

A depsipeptidic analogue of FE399 was efficiently synthesized mainly through macrolactamization using 2-methyl-6-nitrobenzoic anhydride (MNBA), and a detailed investigation of the desired 16-membered macrolactam core of FE399 was performed. It was determined that the combination of MNBA and a catalytic amount of 4-(dimethylamino)pyridine -oxide exhibits much higher activity than that of conventionally used coupling reagents such as hexafluorophosphate azabenzotriazole tetramethyl uronium and benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7876680PMC
http://dx.doi.org/10.1021/acsomega.0c04878DOI Listing

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