Richard W. Tkach

Structures of the aminoglycoside antibiotics 66–40B and 66–40D produced by Micromonospora inyoensis

The novel amino-glycoside antibiotics 66–40B and 66–40D produced as minor components by fermentation of Micromonospora inyoensis have been shown to be O-2,6-diamino-2,3,4,6-tetradeoxy-α-D-glycero-hex-4-enopyranosyl-(1→4)-O-[3-deoxy-3-methylamino-α-D-xylopyranosyl-(1→6)]-2-deoxy-D-streptamine and O-2,6-diamino-2,3,4,6-tetradeoxy-α-D-glycero-hex-4-enopyranosyl-(1→4)-O-[3-deoxy-3-methylamino-β-L-arabinopyranosyl-(1→6)]-2-deoxy-D-streptamine, respectively. The novel 3-deoxy-3-methylamino-β-L-arabinopyranosyl sugar unit of 66–40D has not previously been found in any amino-glycoside antibiotic. Both 66–40B and D exhibit broad spectrum antibacterial activity.

Structure of aminoglycoside 66-40 C, a novel unsaturated imine produced by Micromonospora inyoensis

The aminoglycoside 66-40 C, produced as a minor component in the fermentation of Micromonospora inyoensis, has been shown by spectroscopic and chemical degradative studies to have the novel dimeric structure (5), containing αβ-unsaturated imine groups not previously encountered in any aminoglycoside antibiotic.