Meystre

Additional applications are exemplified by the well-known Meystre-Miescher degradation of the bile acid side chain and, more recently, in the preparation of a-pyrones from a,iS-unsaturated lactones. ... 

The mp of this substance depends on the solvent used for recrystallization. A mp of 171-174 was reported for a sample recrystallized from ether-petroleum ether [K. Heusler, J. Kalvoda, Ch. Meystre, P. Wieland, G. Anner, A. Wettstein, G. Cainelli, D. Arigoni and O. Jeger, Helv. Chim. Acta, 44, 502 (1961)]. 

The preparation of the title lactone has been described by a multistep synthesis from holarrhimine. The method described in detail above is essentially an application of the hypoiodite reaction published by Ch. Meystre and co-workers. These authors also describe the isolgition of the intermediate hemiacetal in pure form. Saturated lactones epimeric at C-20 have also been obtained by chromic acid oxidation of 18,20-dihydroxy compounds which were in turn prepared by treatment of 20-hydroxypregnanes with lead tetraacetate, acetolysis of the resulting 18,20 3-oxides, and hydrolysis. Saturated lactones of the... 

K. Heusler, J. Kalvoda, Ch. Meystre, P. Wieland, G. Anner, A. Wettstein,... 

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