| Popis: |
Fortimicin A and a number of 4-N-acylfortimicins B, although stable as either the fully protonated hydrochloride or sulfate salts, undergo degradation as the free bases in aqueous solution. Detailed studies with fortimicin A and 4-N-acetylfortimicin B have shown that degradation occurs, in part, by simple cleavage of the 4-N-acyl groups with formation of fortimicin B, and, in part, by rearrangement to the 2′-N-acylfortimicins B (the isofortimicin rearrangement). The conversions of the rearrangement products into 2′-N-glycylfortimicin A, 2′-N-acetylfortimicin A, and the 2′-N-(2-aminoethyl)fortimicins A and B are described. The antibacterial activities of the new fortimicin A derivatives are presented. |
