Fimbrolides

Dehydrogenation and dehydration. Some years ago Wells clarified the structure of a known compound 2 obtained by treatment of the dibromolevulinic acid (1) with cone, sulfuric acid. The reaction involves dehydration and loss of two hydrogens. Recently a series of halogenated lactones related to 2, known as fimbrolides,... 

Beechan, C.M. and Sims, J.J. (1979) The first synthesis of fimbrolides, a novel class of halogenated lactones occurring in the red seaweed Delisea fimhriata (Bonnemaisoniaceae). Tetrahedron Lett., 20, 1649-1652. 

De March, P Font J., Gracia, A., and Qingying, Z. (1995) Easy access to 5-alkyl-4-bromo-2(5H)-fliranones synthesis of a fimbrolide, an acetoxyfimbrolide and bromobeckerelide. /. Org. Chem., 60, 1814-1822. 

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