Photoactive derivatives of cellulose were prepared by a mild esterification of the biopolymer with 2-[(4-methyl-2-oxo-2H-chromen-7-yl)oxy]acetic acid via the activation of the carboxylic acid with N,N′ -carbonyldiimidazole. Subsequently, modification with the cationic carboxylic acid (3-carboxypropyl)trimethylammonium chloride was carried out. Thus, water soluble polyelectrolytes decorated with high amounts of photochemically active chromene moieties were obtained. The structures of the novel polysaccharide esters and the polyelectrolytes were evaluated by means of NMR and IR spectroscopy. Moreover, the light triggered photodimerization of the chromene moieties of the photoactive polyelectrolytes was studied by means of UV–Vis spectroscopy in the dissolved state. The photochemistry observed may be used to control the properties of the new polysaccharide derivatives and are thus of interest in the design of smart materials.

中文翻译：

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水溶性光敏纤维素衍生物：纤维素的2-[（（4-甲基-2-氧代-2H-铬基-7-基）氧基]乙酸-（3-羧丙基）三甲基氯化铵混合酯的合成与表征

通过用 N，N' 活化羧酸使生物聚合物与2-[（（4-甲基-2-氧代-2H-铬基-7-基）氧基]乙酸温和酯化制备纤维素的光敏衍生物。 -羰基二咪唑。随后，用阳离子羧酸（3-羧丙基）三甲基氯化铵进行改性。因此，获得了装饰有大量光化学活性色烯部分的水溶性聚电解质。通过NMR和IR光谱法评价了新型多糖酯和聚电解质的结构。此外，通过紫外可见光谱法研究了光活化聚电解质的色烯部分的光触发光二聚化。观察到的光化学可用于控制新多糖衍生物的特性，因此在智能材料设计中引起了人们的兴趣。