Croatica Chemica Acta, Vol. 78 No. 1, 2005.
Original scientific paper
Synthetic Modifications of Ascomycin. V. Access to Novel Ascomycin Derivatives by Replacement of the Cyclohexylvinylidene Subunit
Reinhold Zimmer
Karl Baumann
Hildegard Sperner
Gerhard Schulz
Ewald Haidl
Maximilian A. Grassberger
Abstract
Starting from the easily accessible 24-O-tert-butyldimethylsilyl-22(R)-dihydro-28-oxoascomycin, methodologies that allow replacement of the cyclohexylvinylidene moiety of ascomycin by various other substituents are described. In addition, a so far unknown reactivity of the masked tricarbonyl moiety of ascomycin towards a stabilized Wittig reagent is reported.
Keywords
ascomycin; immunosuppressiva; aldol reaction; oxime; Wittig reaction; oxidation
Hrčak ID:
2661
URI
Publication date:
24.3.2005.
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