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N-methylimidazolium chloride-catalyzed pyrophosphate formation: application to the synthesis of Lipid I and NDP-sugar donors.

ABSTRACT: N-Methylimidazolium chloride is found to catalyze a coupling reaction between monophosphates and activated phosphorous-nitrogen intermediates such as a phosphorimidazolide and phosphoromorpholidate to form biologically important unsymmetrical pyrophosphate diesters. The catalyst is much more active, cheaper, and less explosive than 1H-tetrazole, known as the best catalyst for the pyrophosphate formation over a decade. The mild and neutral reaction conditions are compatible with allylic pyrophosphate formation in Lipid I syntheisis. (31)P NMR experiments suggest that the catalyst acts not only as an acid but also as a nucleophile to form cationic and electrophilic phosphor-N-methylimidazolide intermediates in the pyrophosphate formation.

SUBMITTER: Tsukamoto H

PROVIDER: S-EPMC3156252 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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N-methylimidazolium chloride-catalyzed pyrophosphate formation: application to the synthesis of Lipid I and NDP-sugar donors.

Tsukamoto Hirokazu H Kahne Daniel D

Bioorganic & medicinal chemistry letters 20110422 17

N-Methylimidazolium chloride is found to catalyze a coupling reaction between monophosphates and activated phosphorous-nitrogen intermediates such as a phosphorimidazolide and phosphoromorpholidate to form biologically important unsymmetrical pyrophosphate diesters. The catalyst is much more active, cheaper, and less explosive than 1H-tetrazole, known as the best catalyst for the pyrophosphate formation over a decade. The mild and neutral reaction conditions are compatible with allylic pyrophosp ...[more]

PMID: 21592792

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