Salts of Mosher’s thioacid: agents for determining the enantiomer excess of SN2 substrates

2010 ◽  
Vol 51 (21) ◽  
pp. 2793-2796 ◽  
Author(s):  
Jack E. Richman
Keyword(s):  
2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Ming Hu ◽  
Ying-Xue Yuan ◽  
Weizhou Wang ◽  
Dong-Mi Li ◽  
Hong-Chao Zhang ◽  
...  

AbstractChiral recognition, such as enantioselective interactions of enzyme with chiral agents, is one of the most important issues in the natural world. But artificial chiral receptors are much less efficient than natural ones. For tackling the chiral recognition and enantiomer excess (ee) analysis, up until now all the fluorescent receptors have been developed based on fluorescence intensity changes. Here we report that the chiral recognition of a large number of chiral carboxylic acids, including chiral agrochemicals 2,4-D, is carried out based on fluorescent colour changes rather than intensity changes of AIEgen rotors. Moreover, the fluorescence wavelength of the AIEgen rotor linearly changes with ee of the carboxylic acid, enabling the ee to be accurately measured with average absolute errors (AAE) of less than 2.8%. Theoretical calculation demonstrates that the wavelength change is ascribed to the rotation of the AIEgen rotor upon interaction with different enantiomers.


2020 ◽  
Vol 32 (9) ◽  
pp. 2208-2212
Author(s):  
CH. RAMESH ◽  
DHARMASOTH RAMA DEVI DEVI ◽  
M.N.B. SRINIVAS ◽  
S. RADHA KRISHNA ◽  
NAGARAJU RAJANA ◽  
...  

simple, specific, linear, accurate and precise reverse phase chiral HPLC method was developed for the separation of efavirenz enantiomers by using the Lux Amylose-2 column containing amylose tris(5-chloro-2-methyl phenyl carbamate) as a stationary phase. The mobile phase consists of 0.1 % formic acid in water and acetonitrile (55:45, v/v). The flow rate was kept at 1.0 mL/min and the detection wavelength used 252 nm and the column temperature was set at 25 ºC. The limit of detection was 0.01 mg/mL and the limit of quantification was 0.04 mg/mL. The linearity calibration curve of (R)-enantiomer was shown well from the range of 0.04 mg/mL to 0.4 mg/mL. The values of the correlation coefficient were 0.999 and 0.999 for (R)-enantiomer and (S)-efavirenz, respectively. The percentage recoveries of (R)-enantiomer from efavirenz drug substance were ranged from 93.5% to 107.5%. The results demonstrated that developed RP-chiral HPLC method was simple, precise, robust and applicable for the estimation of (R)-enantiomer in efavirenz API. This method was validated in as per ICH Q2 (R1) and USP validation of compendial methods <1225>.


2004 ◽  
Vol 52 (5) ◽  
pp. 289-294 ◽  
Author(s):  
Masami SAWADA ◽  
Akihiro KAMEI ◽  
Hirotaka UENO ◽  
Hitoshi YAMADA ◽  
Yoshio TAKAI ◽  
...  

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Ming Hu ◽  
Ying-Xue Yuan ◽  
Weizhou Wang ◽  
Dong-Mi Li ◽  
Hong-Chao Zhang ◽  
...  

1996 ◽  
Vol 29 (15) ◽  
pp. 2755-2760 ◽  
Author(s):  
Jingguo Hou ◽  
Hongying Zhou ◽  
Zhiqiang Zhou ◽  
Liren Chen ◽  
Qingyu Ou

Molecules ◽  
2019 ◽  
Vol 24 (21) ◽  
pp. 3944
Author(s):  
Wu ◽  
Wang ◽  
Zhang ◽  
Jin

The enantioselective transformations of indoles preferentially take place in the more-reactive azole ring. However, the methods for the enantioselective functionalization of the indole benzene ring are scarce. In this paper, a series of bifunctional (thio)urea derivatives were used to organocatalyze the enantioselective Friedel−Crafts hydroxyalkylation of indoles with isatins. The resulting products were obtained in good yields (65–90%) with up to 94% enantiomer excess (ee). The catalyst type and the substrate scope were broadened in this methodology.


Sign in / Sign up

Export Citation Format

Share Document