24493-69-4Relevant articles and documents
Simultaneous nucleophilic-substituted and electrostatic interactions for thermal switching of spiropyran: A new approach for rapid and selective colorimetric detection of thiol-containing amino acids
Li, Yinhui,Duan, Yu,Li, Jishan,Zheng, Jing,Yu, Huan,Yang, Ronghua
, p. 4732 - 4738 (2012)
Complementary electrostatic interaction between the zwitterionic merocyanine and dipolar molecules has emerged as a common strategy for reversibly structural conversion of spiropyrans. Herein, we report a concept-new approach for thermal switching of a spiropyran that is based on simultaneous nucleophilic-substitution reaction and electrostatic interaction. The nucleophilic-substitution at spiro-carbon atom of a spiropyran is promoted due to electron-deficient interaction induced by 6- and 8-nitro groups, which is responsible for the isomerization of the spiropyran by interacting with thiol-containing amino acids. Further, the electrostatic interaction between the zwitterionic merocyanine and the amino acids would accelerate the structural conversion. As proof-of-principle, we outline the route to glutathione (GSH)-induced ring-opening of 6,8-dinitro-1′,3′,3′- trimethylspiro [2H-1-benzopyran-2,2′-indoline] (1) and its application for rapid and sensitive colorimetric detection of GSH. In ethanol-water (1:99, v/v) solution at pH 8.0, the free 1 exhibited slight-yellow color, but the color changed clearly from slight-yellow to orange-yellow when GSH was introduced into the solution. Ring-opening rate of 1 upon accession of GSH in the dark is 0.45 s-1, which is 4 orders of magnitude faster in comparison with the rate of the spontaneous thermal isomerization. The absorbance enhancement of 1 at 480 nm was in proportion to the GSH concentration of 2.5 × 10 -8-5.0 × 10-6 M with a detection limit of 1.0 × 10-8 M. Furthermore, due to the specific chemical reaction between the probe and target, color change of 1 is highly selective for thiol-containing amino acids; interferences from other biologically active amino acids or anions are minimal.
Spiropyran-based photoswitchable dimethylaminopyridine
Zhou, Tao,Li, Zhihao,Wang, Jiaobing
, p. 8869 - 8872 (2019/06/17)
Embedding of DMAP in a spiropyran derivative results in a molecular switch 1, which changes the coordination capability of the DMAP moiety upon exposure to external stimuli such as light and heat. In the closed form, 1c behaves as an isolated DMAP, complexing with zinc porphyrin (ZnP) with a high binding constant (K = 1.8 × 104 M-1). However, in the open form, 1o associates with ZnP with a much weaker binding strength (K = 0.5 × 104 M-1). Switching between 1c and 1o is fast and reversible. In the photostationary state under irradiation at 330 nm, 90% of 1 is transformed from 1c to 1o.
Rapid colorimetric sensing of cyanide anion in aqueous media with a spiropyran derivative containing a dinitrophenolate moiety
Shiraishi, Yasuhiro,Itoh, Masataka,Hirai, Takayuki
supporting information; scheme or table, p. 1515 - 1519 (2011/05/16)
A spiropyran derivative containing a dinitrophenolate moiety (2: 1′,3′,3′-trimethyl-6,8-dinitro-spiro-[2H-1-benzopyran-2, 2′-indoline]) behaves as a receptor for selective detection of cyanide anion (CN-) in aqueous media. Compound 2, when dissolved in aqueous media, spontaneously produces the spirocycle-opened merocyanine (MC) form even in dark condition. The absorption band of the MC form decreases selectively upon addition of CN-, via a nucleophilic addition of CN- to the spirocarbon of the MC form. The nucleophilic addition occurs very rapidly (within 1 min) and enables rapid and selective quantification of very low levels of CN- (>0.8 μM) by an absorption analysis.
