Application of 4-Chlorobutyryl Group as Amino Protective Group in the Synthesis of 7-(D-2-Amino-2-phenylacetamido)-3- -methyl-3-cephem-4-carboxylic Acid (Cephalexin)*
نویسنده
چکیده
4-Chlorobutyryl group was used as amino protective group for n(-)-alpha-phenylglycine (I). N-Hydroxysuccinimide ester III was prepared in high yield but partly racemic. Reaction of III or IV with V afforded epimeric mixtures of N,0-protected cephalexins (VI), which can be separated by crystallisation. The 4-chlorobutyryl group in VII was removed under very mild conditions giving cephalexin (IX) in good yield and purity.
منابع مشابه
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