Studies on lactams. Part 65. N-Unsubstituted .beta.-lactams from .beta.-hydroxy-.alpha.-amino acids. Facile preparation of intermediates for isocephalosporins
Synthesis of δ-(l-α-aminoadipoyl)-l-cysteinyl-d-(O-methyl)-d-allothreonine a substrate for isopenicillin-N synthase and its O-methyl-d-threonine epimer
摘要:
The paper describes the synthesis of two epimeric tripeptides delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-(O-methyl)-D-threonine (13) and 6-(L-alpha-aminoadipoyl)-L-cysteinyl-D-(O-methyl)-D-allothreonine (14), modified substrates for the isopenicillin-N synthase enzyme. The D-allothreonine tripeptide (14)has been shown to be an excellent substrate for the enzyme whereas the D-threonine epimer did not react at all. The compound formed by the enzyme with the D-allothreonine tripeptide is a new 2-alpha-methoxypenicillin. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.