Assemble the puzzle: Replacing the N,N-dimethylamino group in classical fluorophores with a four membered azetidine ring provides improved quantum yields. This strategy was extended to four types of bioluminescent firefly luciferin analogues and its differential effect was evaluated. Among them, the benzothiazole core analogue benefited from azetidine substitution and showed improvements of in fluorescence and bioluminescence emission.

中文翻译：

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萤火虫荧光素类似物中氮杂环丁烷取代的差异效应

拼图：用四元氮杂环丁烷环取代经典荧光团中的N、N-二甲氨基可提高量子产率。该策略扩展到四种类型的生物发光萤火虫荧光素类似物，并评估了其差异效应。其中，苯并噻唑核心类似物受益于氮杂环丁烷取代，并显示出荧光和生物发光发射的改善。