On the Structure of Passifloricin A: Asymmetric Synthesis of the δ-Lactones of (2Z,5S,7R,9S,11S)- and (2Z,5R,7R,9S,11S)-Tetrahydroxyhexacos-2-enoic Acid
journal contributionposted on 29.03.2003, 00:00 by Jorge García-Fortanet, Juan Murga, Miguel Carda, J. Alberto Marco
Stereoselective syntheses of the δ-lactone of (2Z,5S,7R,9S,11S)-tetrahydroxyhexacos-2-enoic acid, the structure reported for passifloricin A, and of its (5R)-epimer are described. The creation of all stereogenic centers relied upon Brown's asymmetric allylation methodology. The lactone ring was created via ring-closing metathesis. The NMR data of both synthetic products, however, were different from those of the natural product. The published structure of passifloricin A is thus erroneous and will require further synthetic work to be unambiguously assigned.