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Efficient synthesis of tyrosine-derived marine sponge metabolites via acylation of amines with a coumarin. | LitMetric

Efficient synthesis of tyrosine-derived marine sponge metabolites via acylation of amines with a coumarin.

J Org Chem

Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121-4499, USA.

Published: August 2005

Condensation of N-acetylglycine with aldehyde 15 in acetic anhydride gave acetamido coumarin 16. Hydrolysis to the enol coumarin 17 and reaction with hydroxylamine gave the oximino coumarin 18. Reaction of the oximino coumarin 18 with a range of nucleophiles gave the phenolic oximes in excellent yield. The rates of acylation of histamine with the oximino coumarin 18 and methyl ester 9 were compared. Oxidative spirocyclization of three representative phenolic oximes with polymer-supported (diacetoxyiodo) benzene gave the spiroisoxazolines.

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Source
http://dx.doi.org/10.1021/jo050846rDOI Listing

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