2002 alkaloids

alkaloidsU 0600

25 - 198Cephalostatin Support Studies. Part 20. Redox Refunctionalizationof Steroid Spiroketals. Structure Correction of Ritterazine M. —Structure correction of the title compound is achieved by comparison of spectraof the natural product with some synthetic spiroketal-alcohols obtained byreductive cleavage of the spiroketal and Sharpless asymmetric dihydroxylationof several olefins followed by Suarez iodine(III) oxidative spirocyclizationof monoprotected diols. — (LEE, SEONGMIN; LACOUR, THOMAS G.;LANTRIP, DOUGLAS; FUCHS, PHILIP L.; Org. Lett. 4 (2002) 3, 313-316;Dep. Chem., Purdue Univ., West Lafayette, IN 47907, USA; EN)

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