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Regioselective synthesis of methyl 5-(N-Boc-cycloaminyl)-1,2-oxazole-4-carboxylates as new amino acid-like building blocks.

ABSTRACT: A convenient and efficient synthesis of novel achiral and chiral heterocyclic amino acid-like building blocks was developed. Regioisomeric methyl 5-(N-Boc-cycloaminyl)-1,2-oxazole-4-carboxylates were prepared by the reaction of β-enamino ketoesters (including azetidine, pyrrolidine or piperidine enamines) with hydroxylamine hydrochloride. Unambiguous structural assignments were based on chiral HPLC analysis, ¹H, ¹³C, and ¹⁵N NMR spectroscopy, HRMS, and single-crystal X-ray diffraction data.

SUBMITTER: Bruzguliene J

PROVIDER: S-EPMC8767561 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Regioselective synthesis of methyl 5-(N-Boc-cycloaminyl)-1,2-oxazole-4-carboxylates as new amino acid-like building blocks.

Bruzgulienė Jolita J Račkauskienė Greta G Bieliauskas Aurimas A Milišiūnaitė Vaida V Dagilienė Miglė M Matulevičiūtė Gita G Martynaitis Vytas V Krikštolaitytė Sonata S Sløk Frank A FA Šačkus Algirdas A

Beilstein journal of organic chemistry 20220112

A convenient and efficient synthesis of novel achiral and chiral heterocyclic amino acid-like building blocks was developed. Regioisomeric methyl 5-(N-Boc-cycloaminyl)-1,2-oxazole-4-carboxylates were prepared by the reaction of β-enamino ketoesters (including azetidine, pyrrolidine or piperidine enamines) with hydroxylamine hydrochloride. Unambiguous structural assignments were based on chiral HPLC analysis, 1H, 13C, and 15N NMR spectroscopy, HRMS, and sin ...[more]

PMID: 35096179

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