Semisynthetic aminoglycoside antibacterials. Part 7. Synthesis of novel hexopyranosyl and hexofuranosyl derivatives of gentamine C1 and C1a

Abstract

Acidic hydrolysis of gentamicin C₁ and C_1a provides ready access to the pseudodisaccharides gentamine C₁ and C_1a respectively. Glycosylation of tetrakis-N-benzyloxycarbonylgentamine C₁ and C_1a using the Koenigs–Knorr or Lemieux–Nagabhushan reactions has led to the preparation of a series of novel 6-O-α- and -β-3-amino-3-deoxy- and 2-amino-2-deoxy-D-hexopyranosyl and hexofuranosyl analogues of the gentamicins. The ¹³C n.m.r. properties of representative compounds are described and the rotamer populations about the C-4–O and C-6–O glycosidic bonds are discussed.