வேதியியல் அறிவியல் இதழ்

A highly efficient, solvent-free and versatile greener protocol was developed for the synthesis of coumarins from resorcinol an ethyl acetoacetate via Pechmann condensation using heterogeneous recyclable FeCl₃/MCM41 catalyst. This method is simple, cost effective, and benefits from the elimination of waste streams generated with conventional acid catalysts. The influence of catalyst calcination temperature as well as various solvent on conversion and product selectivity has also been studied in this work. The developed FeCl₃/ MCM41 catalysts showed excellent catalytic performance with 60%-75% yields for coumarins, depending on the catalyst pretreatment and reaction conditions used. Moreover, FeCl₃/MCM41 catalyst treated at 400°C can be reused efficiently for five times without a significant loss of its activity, which was attributed to synergistic effects of metal-support interactions, especially unique acid-redox properties of FeCl₃.

The present paper reports the simple, rapid, accurate and precise RP-HPLC method for the simultaneous estimation of Perindopril erbumine and Amlodipine besylate in bulk and formulated drug substance. The reverse phase liquid chromatographic analysis has been performed on a Kromasil C8 (4.6 mm × 250 mm, 5 µ particle size) column with mobile phase Buffer (6.8 g Potassium dihydrogen orthophosphate) and Acetonitrile in the ratio 59:41 with adjusted pH 2.6 with orthophosphoric acid and column oven temperature 40°C. The flow rate of mobile phase was adjusted 1.0 ml/min. and the injection volume 10 µl. Detection was performed at 210 nm. The retention time of Perindopril erbumine and Amlodipine Besylate were found to be 4.483 min. and 6.767 min, the linearity was observed in the concentration range from 20% to 160% of nominal concentration of Perindopril erbumine and Amlodipine Besylate correlation coefficient was 0.999 for both drugs. The % recovery was found to be within the limits of the acceptance criteria with average recovery of 99.4% for perindopril erbumine and 99.6% for Amlodipine besylate. The % RSD below 2.0 shows high precision of proposed method.