title: First synthesis and structural elucidation of (-)-presphaerene.
abstract: The first total synthesis of (-)-presphaerene (1) was achieved from (R)-glyceraldehyde 9 in 19 steps, demonstrating the novel "folding and allylic strain-controlled" intramolecular ester enolate S(N)2' alkylation strategy could be extended to the stereoselective synthesis of cyclopentanoid natural products. The present study also established the relative and absolute stereochemistry of 1, and the absolute structures of co-occurring sphaeroanes from the red alga Sphaerococcus coronopifolius.
authors.affiliation: College of Pharmacy, Seoul National University, San 56-1, Shillim-Dong, Kwanak-Ku, Seoul 151-742, Korea. jongkook91@hanmail.net
authors.forename: Jongkook
authors.initials: J
authors.lastname: Lee
authors.forename: Jiyong
authors.initials: J
authors.lastname: Hong
mesh_terms: D003517:Cyclopentanes / Q000138:chemical synthesis* / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D021241:Spectrometry, Mass, Electrospray Ionization; D013237:Stereoisomerism
chemical_list: D003517:Cyclopentanes; C502482:presphaerene