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Updated: Jul 6, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Long-chain 2H-azirines with heterogeneous terminal halogenation from the marine sponge Dysidea fragilis
Colin K Skepper1, Tadeusz F Molinski
1Department of Chemistry and Biochemistry, University of California, San Diego, MC0358, 9500 Gilman Drive, La Jolla, CA 92093, USA.
Abstract:
Three new omega-halogenated long-chain 2H-azirines were isolated from the sponge Dysidea fragilis. Their structures revealed heterogeneity in both the composition of the terminal 1,1-dihalo-vinyl group and enantiomeric ratios at C2 of the azirine-2-carboxylate ester terminus. Azirine-2-carboxylate esters were shown to racemize spontaneously. A hypothesis is proposed for the biosynthesis of the azirinecarboxylate family of natural products that involves enzyme-catalyzed free radical halogenation followed by elimination of hydrohalic acid.
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