Abstract Along with cellulose, lignin is one of the most common polymers of plant origin. Numerous studies show that the complex and irregular structure of lignin is still unknown. First of all, the existing problems are connected with the peculiarities of lignins as a natural chemical compound. In this paper the general regularities of the chemical structure of dioxane lignins isolated from the softwood – larch (Lárix sibírica), pine (Pinus cembra) and juniper (Juníperus commúnis). The studies were carried out using a combination of 13C, 31P and 2D NMR spectroscopy. According to HSQC spectra it was established that the main structural fragments are the structures of β-aryl ether, followed by phenylcoumarans, with lower amounts of other substructures. Signals belonging to a methyl substituted phenylcoumaron were first identified on the NMR spectra of softwood dioxane lignins. Signals related to the structure of 3′-O-methylated dihydroquercetin were found in the composition of larch dioxane lignin.

中文翻译：

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根据一维和二维核磁共振光谱，不同软木木质素的结构特征

摘要 与纤维素一样，木质素是最常见的植物来源聚合物之一。大量研究表明，木质素的复杂和不规则结构仍然未知。首先，存在的问题与木质素作为天然化合物的特性有关。在本文中，从针叶木中分离出的二恶烷木质素的化学结构的一般规律 - 落叶松 (Lárix sibírica)、松树 (Pinus cembra) 和杜松 (Juníperus commúnis)。这些研究是使用 13C、31P 和 2D NMR 光谱的组合进行的。根据 HSQC 光谱，确定主要结构片段是 β-芳基醚的结构，其次是苯基香豆素，其他亚结构的含量较低。属于甲基取代的苯基香豆素的信号首先在软木二恶烷木质素的 NMR 谱上得到鉴定。在落叶松二恶烷木质素的组成中发现了与 3'-O-甲基化二氢槲皮素结构相关的信号。