Kinetic Features of Rearrangement of 3-Hydroxy-3-phenyl-indan-1,2-dione into 2,3- Epoxy-2-hydroxy-1-indanone in Acetonitrile in Dark | Chapter 2 | Chemical and Materials Sciences: Developments and Innovations Vol. 8

3-hydroxy-3-phenyl-indan-1,2-dione (dione) in acetonitrile (ACN) is converting back into 2,3-epoxy-2-hydroxy-1-indanone (epoxide) in dark. This is another equally significant observation after the detection of epoxide as the primary product in the photochemical reactions of 3-hydroxy-2-phenyl-4H-chromen-4-one (3HF) in ACN. A well-purified and characterized sample of dione has been taken for these studies. The electronic absorption spectrum of dione in ACN is changing continuously and kinetically in dark. This observation has been studied at 22±1 °C in detail. Concentration and spectra of both dione and epoxide at different times were obtained from their mixture after working out the absorption coefficients for the pure components at different wavelengths. From this data kinetic features of this reaction have been examined. Considering dione and epoxide to be in equilibrium, an equation has been derived that shows the linear dependence on a factor of concentration of dione vs time and also for concentration of epoxide vs time. The linear plots confirm the reversibility of the reaction. It can also be said that both the forward and backward reactions are first order since the derived equations are based on this assumption. It was also observed that this reaction is temperature-dependent as expected. Reaction has been studied at 14±1 and 32±1 °C also and from this data, rate constants for the forward and backward reactions were obtained. From the plots of lnk1 and lnk2 vs T activation energies, come out to be 72.175 kJmol^-1 and 71.824 kJmol^-1 for the conversion of dione into epoxide and from epoxide to dione.

 

Author (s) Details

 

Jyoti Tomar
Department of Chemistry, Punjabi University Patiala, Punjab, Pin Code- 147002, India.

 

Manisha Bansal
Department of Chemistry, Punjabi University Patiala, Punjab, Pin Code- 147002, India.

 

Please see the book here:- https://doi.org/10.9734/bpi/cmsdi/v8/3349

Development and Validation of HPLC Assay Method of Tofisopam by QBD Approach | Chapter 6 | Novel Aspects on Pharmaceutical Research Vol. 8

The aim of the work is to develop and confirm novel, simple, increased reversed phase chromatography form for assay of Tofisopam in pure and pill form. Quality by design (QBD) refers to the achievement of sure predictable character with desired and fixed specifications. The QbD approach stresses product and process understanding with character risk management and controls, happening in higher assurance of crop quality, regulatory elasticity, and continual bettering. The experimental trial was by Box Behnken design using Design Expert® program 10 version. The attributes picked were peak symmetry, NTP and peak purity. The forecasted data compensated with actual exploratory data. The exploratory design suggested the robust MODR domain for the TF HPLC method development. All the approved parameters were inside the acceptable criteria of ICH directions. The optimized chromatographic environments required quaternary send with travelling phase of Water: Acetonitrile 25:75 v/v at 1 ml/min, microwave temperature at 25oC at 310 nm utilizing C18 (250 X 4.6 mm Id, 5μm) column and PDA detector accompanying a run time of 5 brief time period. In this investigation, three independent variables-peak proportion, retention time, and NTP-were used to decide the concentration of the natural phase, oven hotness, and flow rate. The linearity design, precision, accuracy, and precision were all verified. With an overall average veracity of 99.98%, the approach provided linear reactions spanning the aggregation range of 4 to 24 ppm. Regarding the tofisopam retention time, the approach was trustworthy, repeatable, and precise.

Author(s) Details:

Megha Kokane,
Department of Quality Assurance, Shri. D. D. Vispute College of Pharmacy & Research Center, New Panvel, Navi Mumbai-410206, Maharashtra, India.

Jeeja Pananchery,
Department of Pharmacognosy, D. Y. Patil Deemed to be University School of Pharmacy, Nerul, Navi Mumbai-400507, Maharashtra, India.

Monika Jadhav,
Department of Quality Assurance, C. U. Shah College of Pharmacy, SNDT Women’s University, Sir Vithaldas Thakersay, Santacruz West, Juhu, Mumbai-400049, Maharashtra, India.

Ashish Jain,
Shri. D. D. Vispute College of Pharmacy & Research Center, New Panvel, Navi Mumbai-410206, Maharashtra, India.

Please see the link here: https://stm.bookpi.org/NAPR-V8/article/view/11653