An LC method involving a C18 column as stationary phase and a mixture of aqueous sodium dihydrogen phosphate (0.2 M; pH of the buffer adjusted to 6.3 ±0.1 with 3.6 % w/v sodium hydroxide solution) and methanol in the ratio (60:40, v/v) as mobile phase was developed for the effective separation of all degradation products. It involved 1ml min−1 flow rate and detection wavelength of 317 nm. The developed method was found to be precise, accurate, specific and selective. The drug showed instability in solution state under alkaline, photolytic and UV stress conditions, but was relatively stable in the acid, oxidative, neutral, dry and wet heat degradation. Primarily, maximum degradation products were formed under alkaline conditions. The products formed under different stress conditions were investigated by LC and the major degraded product of alkali degradation sample by LC & MS. In the MS of pure drug m/z values and fragmentation patterns matched with starting material used in synthesis. The alkaline degraded products were characterized through MS fragmentation studies. Based on the results, a more complete degradation pathway for the drug could be proposed.
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