(1Z)-1-[2-(2-Nitrophenyl)hydrazinylidene]naphthalen-2(1H)-one (1), (4Z)-5-methyl-2-phenyl-4-(2-phenylhydrazinylidene)-2,4-dihydro-3H-pyrazol-3-one (2), (4Z)-5-methyl-4-[2-(2-nitrophenyl)hydrazinylidene]-2-phenyl-2,4-dihydro-3H-pyrazol-3-one (3) and 3,5-dinitro-4-[(2Z)-2-(2-oxonaphthalen-1(2H)-ylidene)hydrazinyl]benzoic acid (4) were prepared and one- and two-dimensional ¹⁵N, ¹³C and ¹H NMR spectra were measured and analysed. Results obtained were used in characterization of these compounds from viewpoint of azo-hydrazo tautomerism. All these compounds exist almost completely in appropriate hydrazo forms in dimethyl sulfoxide. Advantages of NMR spectroscopy application in determination of acidic proton positions and azo-hydrazo content determination are discussed.

中文翻译：

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重新解释了4-羧基-2,6-二硝基苯基偶氮羟基萘的互变异构体NMR

（1Z）-1- [2-（2-硝基苯基）肼基]萘-2（1H）-（1），（4Z）-5-甲基-2-苯基-4-（2-苯基肼基）-2， 4-二氢-3H-吡唑-3-一（2），（4Z）-5-甲基-4- [2-（2-硝基苯基）肼基] -2-苯基-2,4-二氢-3H-吡唑-制备3-一（3）和3,5-二硝基-4-[（2Z）-2-（2-氧杂萘-1（2H）-亚烷基）肼基]苯甲酸（4），并进行一维和二维¹⁵ N，¹³ C和¹测量和分析1 H NMR谱。从偶氮-肼互变异构的观点，将获得的结果用于表征这些化合物。所有这些化合物几乎都以适当的肼形式完全存在于二甲基亚砜中。讨论了NMR光谱在确定酸性质子位置和确定偶氮-azo含量上的优势。