Bromination of myo-inosadiamine-1,3 dihydrochloride or its di-N-acetyl derivative with acetyl bromide and acetic anhydride yielded pentaacetyl-2-bromo-2-deoxy-scyllo-inosadiamine-1,3 (III), which upon reductive debromination afforded pentaacetyl-2-deoxystreptamine (IV). The configurations of the new compounds obtained were established by nuclear magnetic resonance and chemical evidences. A mechanism of the bromination reaction is presented, based on the configuration of the bromo-compound.2-Deoxystreptamine has been found as a component of the antibiotics neomycin,1) kanamycin,2) paromomycin,3,4) and gentamicin.5)The structure and configuration was established to be a 1,3-diamino-4,5,6-cyclohexanetriol with the all-trans configuration, by analogy of the stereochemistry of streptamine,6) and this has been further confirmed by Lemieux by nuclear magnetic resonance (NMR) spectroscopy.7)In the present study we wish to report a two step synthesis of 2-deoxystreptamine from myo-inosadiamine-1,3.6) When myo-inosadiamine-1,3 dihydrochloride (I)9) or its di-N-acetyl derivative (II) are heated in a mixture of acetyl bromide and dec.) are obtained in 48 and 16% yield. The structure and configuration of this product was established to be pentaacetyl-2-bromo-2-deoxyscyllo-inosadiamine-1,3 (III) by elementary analysis, the NMR spectroscopic data and chemical evidence as described below.

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Redox-active phenazinium salts bonded to amphiphilic polymer backbones are demonstrated to function as high-performance electron-transfer mediators in enzymatic bioanodes applicable to biofuel cells. The redox-active moieties could be easily tethered to the electrodes by physical adsorption of the hydrophobic regions of the polymer backbones onto the electrode surface. On the other hand, long hydrophilic chains were essential to ensure high mobility of the redox-active moieties in aqueous solutions and to enhance their electron-transfer properties. We found that an amphiphilic mediator with a linear polymer backbone exhibited stable adsorption behavior on the electrode surface and generated high bioelectrocatalytic current (>1.8 ± 0.32 mA/cm) in the presence of pyrroloquinoline quinone-dependent glucose dehydrogenase and an aqueous solution of glucose fuel. This current was more than two times higher than that of an electrode treated with a low-molecular-weight phenazinium salt. Moreover, the bioelectrode modified with the polymer mediator retained the high electrocatalytic current after 10 exchanges of the glucose fuel. The mediator-modified bioelectrodes are expected to be useful for various bio-related energy and electronic devices.

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