文献类型：期刊文献

英文题名：pH-dependent photoinduced electron transfer of 1,8-naphthalimide derivatives: Effects of regiochemistry, substituent at 4-position and proton receptor

作者：Xie, Xinyang[1];Zhang, Yiqi[1];Liu, Siyi[1];Yu, Zhihao[1];Zhang, Guangzhu[1];Zhang, Weibing[1];Qian, Junhong[1]

机构：[1]East China Univ Sci & Technol, Sch Chem & Mol Engn, Shanghai Key Lab Funct Mat Chem, Shanghai 200237, Peoples R China

年份：2026

卷号：1353

外文期刊名：JOURNAL OF MOLECULAR STRUCTURE

收录：;EI(收录号：20254719549664);WOS:【SCI-EXPANDED(收录号:WOS:001628511600008)】；

基金：This work was financially supported by National Key Research and Development Program of China (2022YFD1700400) .

语种：英文

外文关键词：Naphthalimide; Fluorescent isomer; Photoinduced electron transfer; Path-selective; Acetylation

摘要：A series of naphthalimide-based (NPA) isomers were designed and synthesized for fluorescent detection of aqueous pH. In these probes, three proton receptors with different pK(a), i.e. piperidine, morpholine and N,N-dimethylaniline were covalently connected at 4-position or imide site to construct "receptor-spacer-fluorophore" systems, where photoinduced electron transfer (PET) is assumed to occur from the receptor to the fluorophore. For the probes with piperidine or morpholine as the receptor (compounds 1A-B and 2A-B), PET exhibit path-selective, namely from the distal tertiary amine at 4-substituent to NPA and resulted in fluorescence quenching. For N,N-dimethylaniline derivatives (3A, 3B), strong PET processes happen no matter where the receptor is situated. Acetylation of 4-amino improved the PET efficiency of all the probes and made PET happen from both directions (4-position and imide site) to the fluorophore by tuning the local electric field. Protonation of the receptor triggered significant fluorescence enhancements of 3A-Ace and 3B (> 100-fold), and their pK(a) values were estimated to be 4-5, which rendered their application in monitoring lysosomal pH in living cells.