Model 880 pu intelligent hplc pump

The cLC analyses of the enantiomeric purity were performed on a Jasco model 880-PU Intelligent HPLC pump (JASCO Corporation, Tokyo, Japan), equipped with a JASCO model 880-30 solvent mixer involving an 875-UV intelligent UV-vis detector and a 7125 injector (Rheodyne LCC., Rohnert Park, California) fitted with a 20 μL loop. The data were handled on ChromNAV Chromatography Data System (version 1.19.1) from JASCO Corporation (Tokyo, Japan). The chromatographic column used was (S,S)-Whelk-O1^® (25 cm × 4.6 mm i.d., 5 µm particle size, 100-Å pore size) from Regis Technologies, Inc. (Morton Grove, IL, USA. The mobile phase was degassed in an ultrasonic bath for 15 min after preparation in a volume/volume ratio. Analyses were performed at 25 ± 2 °C in isocratic mode. The flow rate used was 0.5 mL/min, and the working pressure was between 30 and 35 bar. The chromatograms were monitored by UV at a wavelength of 254 nm. The sample injections (10 µL) were carried out in triplicate. The column void time (t₀) was considered to be equal to the peak of the solvent front and was taken from each particular run. The e.r. was determined by the relative percentages of the peak areas according to e.r. (%) = 100 × ([R]/([R] + [S]) or 100 × ([S]/([S] + [R]), where [S] and [R] are the area of the peak of each enantiomer [64 (link)].

Compounds 22–32 were prepared using HPLC grades n-hexane : EtOH (50 : 50) at a final concentration 50 μg mL⁻¹, and the injection volume was 10 μL. The HPLC system comprised a JASCO model 880-PU intelligent HPLC pump (JASCO corporation, Tokyo, Japan), equipped with a 7125 injector (Rheodyne LCC, Rohnert Park, CA, USA) fitted with a 20 μL LC loop, a JASCO model 880–30 solvent mixer involving a 875-UV intelligent UV/VIS detector, a system equipped with a chiral column (Lux® 5 μm amylose-1, 250 × 4.6 mm). The data acquisitions were performed using ChromNAC chromatography Data system (version 1.19.1) from JASCO Corporation (Tokyo, Japan). The mobile phase consisted of the mixture of n-hexane : EtOH (90 : 10, v/v), at a flow rate of 0.5 mL min⁻¹. The mobile phase was prepared in a volume/volume ratio and degassed in an ultrasonic bath for at least 15 min before use. Chromatographic analyses were carried out in isocratic mode at 22 ± 2 °C, in duplicate. The UV detection was performed at a wavelength of 254 nm. The volume void time was considered to be equal to the peak of solvent front and was taken from each particular run. The enantiomeric ratios (e.r) were determined by the mean percentage of peak area of eluted peaks.