2-Hydroxygentamicin C2 60768-15-2 BRN 1408132 D-Streptamine, O-3-deoxy-4-C-methyl-3-(methylamino)-beta-L-arabinopyranosyl-(1-6)-O-(2,6-diamino-2,3,4,6,7-pentadeoxy-alpha-D-ribo-heptopyranosyl-(1-4))-