2001 antibiotics

antibioticsU 1200

02 - 228Synthesis of the C38–C44 Segment of Altohyrtin A – With anAddendum on the Preparation of 8-Oxabicyclo[3.2.1]oct-6-en-3-one.— A straightforward asymmetric synthesis of the title fragment (X) in tensteps and 28% overall yield is presented, involving the desymmetrization ofmeso-oxabicyclooctenone (IV) by lithiation with a chiral lithium amide as keystep. Additionally, an improved large-scale synthesis of oxabicyclooctenone(IV) is presented and some remarks to performance and work-up procedures aregiven. — (KIM, H.; HOFFMANN, H. M. R.; Eur. J. Org. Chem. (2000) 12,2195-2201; Inst. Org. Chem., Univ. Hannover, D-30167 Hannover, Germany;EN)

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