Unambiguous assignments have been made for each individual pK_a value of the amino group and guanidine substituents on 2-deoxystreptamine, neamine, neomycin, paromomycin, and streptomycin by pH-titration evaluation of their ¹H, ¹³C, and ¹⁵N (by ¹H-¹⁵N heteronuclear multiple-bond correlation (HMBC) spectra) NMR chemical shifts (δ_Xs) as the reporter nuclei. These data require minor revisions of the literature data in terms of the assignment order for neomycin and paromomycin. In situ titrations and NMR spectroscopy are shown to be a powerful combination for rapidly (minutes) obtaining each distinct pK_a value of the similar amine and guanidine functional groups, which decorate aminoglycoside antibiotics.

中文翻译：

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多核核磁共振波谱用于快速准确地确定2-脱氧链胺胺，神经胺，新霉素，巴龙霉素和链霉素的单个p K _a值

通过对¹ H，¹³ C和¹⁵ N的pH滴定评估，对每个个体p K_的2- K脱氧链胺胺，神经胺，新霉素，巴龙霉素和链霉素的氨基和胍基取代基进行了明确赋值¹ H- ¹⁵ ñ异核多键相关（HMBC）光谱）NMR化学位移（δ _X或多个）作为报道核。这些数据需要根据新霉素和巴龙霉素的分配顺序对文献数据进行较小的修改。原位滴定和NMR光谱显示了快速（分钟）获得每种不同p K _a的强大组合 修饰氨基糖苷类抗生素的类似胺和胍官能团的价值