1999 antibiotics

antibioticsU 1200

11 - 277A Novel Aldol Condensation with 2-Methyl-4-pentenal and ItsApplication to an Improved Total Synthesis of Epothilone B. —Addition of the enolate of compound (II) to optically active aldehydes providesproducts with good anti selectivity in the case of (IIIa)-(IIIc), among them theprecursor (IVa) for the route to the title macrolide (XI). Suzuki coupling ofcompound (VII) and reduction of ketone (IX) under modified Noyori conditionsgive access to alcohol (X), which is converted by a previously reported route tothe target compound. — (BALOG, A.; HARRIS, C.; SAVIN, K.; ZHANG,X.-G.; CHOU, T. C.; DANISHEFSKY, S. J.; Angew. Chem., Int. Ed. 37(1998) 19, 2675-2678; Lab. Bioorg. Chem., Sloan-Kettering Inst. Cancer Res.,Cornell Univ., New York, NY 10021, USA; EN)

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1999 antibiotics

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