2-(Benzothiazol-2-yl)-phenyl-β-d-galactopyranoside derivatives as fluorescent pigment dyeing substrates and their application for the assay of β-d-galactosidase activities
摘要:
2-(Benzothiazol-2-yl)-phenyl-beta-D-galactopyranoside derivatives were synthesized as novel artificial fluorescent pigment dyeing substrates for beta-D-galactosidase. The substrates, which exhibited non-fluorescence or weak fluorescence in solution phase, were smoothly hydrolyzed by beta-D-galactosidase from Aspergillus oryzae and yielded a water-insoluble strong fluorescent pigment. The difference of fluorescent intensity exhibited a linear relationship with the amount of enzyme. (C) 2013 Elsevier Ltd. All rights reserved.
Synthesis, and In Vitro and In Silico α-Glucosidase Inhibitory Studies of 5-Chloro-2-Aryl Benzo[d]thiazoles
摘要:
Twenty-five derivatives of 5-chloro-2-aryl benzo[d]thiazole (1-25) were synthesized and evaluated for their alpha-glucosidase (S. cerevisiae EC 3.2.1.20) inhibitory activity in vitro. Among them eight compounds showed potent activity with IC50 values between 22.1 +/- 0.9 and 136.2 +/- 5.7 mu M, when compared with standard acarbose (IC50 = 840 +/- 1.73 mu M). The most potent compounds 4, 9, and 10 showed IC50 values in the range of 22.1 +/- 0.9 to 25.6 +/- 1.5 mu M. Compounds 2, 5, 11, and 19 showed IC50 values within the range of 40.2 +/- 0.5 to 60.9 +/- 2.0 mu M. Compounds 1 and 3 were also found to be good inhibitors with IC50 values 136.2 +/- 5.7 and 104.8 +/- 9.9 lM, respectively. Their activities were compared with alpha-glucosidase inhibitor drug acarbose (standard) (IC50 = 840 +/- 1.73 mu M). The remaining compounds were inactive. Structure-activity relationships (SAR) have also been established. Kinetics studies indicated compounds 2, 3, 10, 19, and 25 to be non-competitive, while 1, 5, 9, and 11 as competitive inhibitors of alpha-glucosidase enzyme. All the active compounds (1-5, 9-11, and 19) were also found to be non-cytotoxic, in comparison to the standard drug i.e., doxorubicin (IC50 = 0.80 +/- 0.12 mu M) in MTT assay. Furthermore, molecular interactions of active compounds with the enzyme binding sites were predicted through molecular modeling studies. (C) 2018 Elsevier Inc. All rights reserved.
Consecutive cross-dehydrogenative C–O and C–N construction for the synthesis of polyarene with AIE properties under electrochemical condition involving oxygen radical species
A practical and scalable protocol for the regioselective C–H phenoxylation and azolation of phenol derivatives via consecutive electro-oxidative CDC reaction has been demonstrated. The reaction runs under metal-, oxidant- and reagent-free conditions, allowing for the efficient construction of a diaryl ether skeleton by the O-radical participating pathway and a subsequent electro-induced nucleophilic
已经证明了通过连续电氧化 CDC 反应对苯酚衍生物进行区域选择性 C-H 苯氧基化和唑化的实用且可扩展的方案。该反应在无金属、氧化剂和试剂的条件下进行,允许通过 O 自由基参与途径有效构建二芳基醚骨架,并随后在唑类和原位之间进行电诱导亲核取代 (S N Ar )生成苯酚衍生物。电解策略为形成具有各种荧光特性的聚芳烃提供了一条捷径,并且适用于定量产率的克级合成。最后,对机理研究进行了 DFT 计算。
Copper-Catalyzed Cross Dehydrogenative Coupling of<i>N</i>,<i>N</i>-Disubstituted Formamides and Phenols: A Direct Access to Carbamates
作者:Wajid Ali、Saroj K. Rout、Srimanta Guin、Anju Modi、Arghya Banerjee、Bhisma K. Patel
DOI:10.1002/adsc.201400659
日期:2015.2.9
AbstractAn efficient copper‐catalyzed protocol has been developed for the synthesis of carbamates from dialkylformamides and phenols possessing directing groups such as benzothiazole, quinoline and formyl at the ortho‐position. In this chelation assisted approach, CO bond formation takes place via a cross dehydrogenative coupling (CDC) between the formyl CH of dialkylformamide and phenolic OH in the presence of copper(II)acetate/aqueous tert‐butyl hydroperoxide. Under identical reaction conditions, salicylic acid derivatives underwent amidation with the carboxylic group rather than formamidation of the phenolic OH. The use of a cheap and environmentally benign catalyst along with the tolerance of a wide range of functional groups makes this an easy, phosgene‐free route to carbamates.magnified image