Antipodal forms of cephem derivatives via stereochemical manipulations of the cephalosporin nucleus

Abstract

Two complementary strategies have been developed in order to convert a cephalosporin derivative, characterized by the ‘natural’ absolute configuration of the two stereogenic centers, into its enantiomer, as an optically pure compound.

References

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12. The only epimer absent in the routes described is the enantiomer of sulfoxide 11, which can be obtained, together with 9, by direct oxidation of 3.