Biothiols,including cysteine(Cys),homocysteine(Hey),and glutathione(GSH) play important roles in physiological processes,and the detection of thiol using fluorescent probes has attracted attention due to their high se...Biothiols,including cysteine(Cys),homocysteine(Hey),and glutathione(GSH) play important roles in physiological processes,and the detection of thiol using fluorescent probes has attracted attention due to their high sensitivity and selectively and invasive on-time imaging.However,the similar structures and reactivity of these biothiols present great challenges for selective detection.This review focused on the the "aromatic nucleophilic substitution-rearrangement(SNAr-rearrangement) mechanism",which provided a powerful tool to design fluorescent probes for the discrimination between biothiols.We classify the fluorescent probes according to types of fluorophores,such as difluoroboron dipyrromethene(BODIPY),nitrobenzoxadiazole(NBD),cyanine,pyronin,naphthalimide,coumarin,and so on.We hope this review will inspire exploration of new fluorescent probes for biothiols and other relevant analytes.展开更多
I.INTRODUCTION Hypocrellin A(abbreviated HA) from Hypocrellia bambusae (B. ct Br.)sacc. growing in Yunnan Province, China, is an efficient phototherapeutic agent. Recently HA irradiation with visible light has been su...I.INTRODUCTION Hypocrellin A(abbreviated HA) from Hypocrellia bambusae (B. ct Br.)sacc. growing in Yunnan Province, China, is an efficient phototherapeutic agent. Recently HA irradiation with visible light has been successfully used for the treatment of white lesions of vulva and vitiligo. In molecular level, studies on phototherapeutic mechanism have been focused on the structure, photophysical and photochemical properties of HA and its derivatives. The photoreactions, which are closely related to phototherapeutic activities, have not been re-展开更多
The 1-azido-2-chloro-4-nitrobenzene was prepared by nucleophilic substitution between 2-chloro-4-nitro-1-(trifluoromethylsulfinyl)benzene and sodium azide, and its structure was characterized by NMR spectrum and X-ray...The 1-azido-2-chloro-4-nitrobenzene was prepared by nucleophilic substitution between 2-chloro-4-nitro-1-(trifluoromethylsulfinyl)benzene and sodium azide, and its structure was characterized by NMR spectrum and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group P21/n, Z = 8 and Mr = 198.57. A cultivation process of the single crystal of unstable aryl azide was provided. The group of trifluoromethyl sulfinyl was found for the first time to be a new excellent leaving group of aromatic nucleophilic substitution reactions.展开更多
Our previous research showed that aliphatic amines were put in order of high reactivity as “ethylamine > ammonia > t-butylamine > diethylamine” on the aromatic nucleophilic substitution of 1-dimetylamino-2,...Our previous research showed that aliphatic amines were put in order of high reactivity as “ethylamine > ammonia > t-butylamine > diethylamine” on the aromatic nucleophilic substitution of 1-dimetylamino-2,4-bis(trifluoroacetyl)-naphthalene 1 in acetonitrile. The DFT calculation study (B3LYP/6-31G* with solvation model) for the reactions of 1 with above four amines rationally explained the difference of each amines reactivity based on the energies of their Meisenheimer complexes 3 which are assumed to formed as the reaction intermediates in the course of the reaction giving the corresponding N-N exchange products 2. Intramolecular hydrogen bond between amino proton in 1-amino group and carbonyl oxygen in 2-trifluoroacetyl group stabilizes Meisenheimer complexes 3 effectively, and accelerates the substitution reaction from 1 to 2. Our calculation results also predicted that the above order of amines is also true if less polar toluene is used as a solvent instead of acetonitrile even though more enhanced conditions are required.展开更多
Unsymmetrical sulfides can be generated by the reaction of chlorine substituted aromatic compounds in sulfoxide in the presence of fluorine anion in fair yield. A likely mechanism was proposed.
基金financially supported by the National Natural Science Foundation of China (No. 21525206)
文摘Biothiols,including cysteine(Cys),homocysteine(Hey),and glutathione(GSH) play important roles in physiological processes,and the detection of thiol using fluorescent probes has attracted attention due to their high sensitivity and selectively and invasive on-time imaging.However,the similar structures and reactivity of these biothiols present great challenges for selective detection.This review focused on the the "aromatic nucleophilic substitution-rearrangement(SNAr-rearrangement) mechanism",which provided a powerful tool to design fluorescent probes for the discrimination between biothiols.We classify the fluorescent probes according to types of fluorophores,such as difluoroboron dipyrromethene(BODIPY),nitrobenzoxadiazole(NBD),cyanine,pyronin,naphthalimide,coumarin,and so on.We hope this review will inspire exploration of new fluorescent probes for biothiols and other relevant analytes.
基金Project supported by the National Natural Science Foundation of China
文摘I.INTRODUCTION Hypocrellin A(abbreviated HA) from Hypocrellia bambusae (B. ct Br.)sacc. growing in Yunnan Province, China, is an efficient phototherapeutic agent. Recently HA irradiation with visible light has been successfully used for the treatment of white lesions of vulva and vitiligo. In molecular level, studies on phototherapeutic mechanism have been focused on the structure, photophysical and photochemical properties of HA and its derivatives. The photoreactions, which are closely related to phototherapeutic activities, have not been re-
文摘The 1-azido-2-chloro-4-nitrobenzene was prepared by nucleophilic substitution between 2-chloro-4-nitro-1-(trifluoromethylsulfinyl)benzene and sodium azide, and its structure was characterized by NMR spectrum and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group P21/n, Z = 8 and Mr = 198.57. A cultivation process of the single crystal of unstable aryl azide was provided. The group of trifluoromethyl sulfinyl was found for the first time to be a new excellent leaving group of aromatic nucleophilic substitution reactions.
文摘Our previous research showed that aliphatic amines were put in order of high reactivity as “ethylamine > ammonia > t-butylamine > diethylamine” on the aromatic nucleophilic substitution of 1-dimetylamino-2,4-bis(trifluoroacetyl)-naphthalene 1 in acetonitrile. The DFT calculation study (B3LYP/6-31G* with solvation model) for the reactions of 1 with above four amines rationally explained the difference of each amines reactivity based on the energies of their Meisenheimer complexes 3 which are assumed to formed as the reaction intermediates in the course of the reaction giving the corresponding N-N exchange products 2. Intramolecular hydrogen bond between amino proton in 1-amino group and carbonyl oxygen in 2-trifluoroacetyl group stabilizes Meisenheimer complexes 3 effectively, and accelerates the substitution reaction from 1 to 2. Our calculation results also predicted that the above order of amines is also true if less polar toluene is used as a solvent instead of acetonitrile even though more enhanced conditions are required.
基金Hui LOU thanks the Natural Science Foundation of Zhejiang Province (No.299024).
文摘Unsymmetrical sulfides can be generated by the reaction of chlorine substituted aromatic compounds in sulfoxide in the presence of fluorine anion in fair yield. A likely mechanism was proposed.
