In order to explore the anticancer and antimicrobial activity associated with the thiazolone framework, several new (Z)-2-((5-(3fluorobenzylidene)-4-oxo-4,5-dihydrothiazol-2-yl)amino)carboxylic acid derivatives have been synthesized in water as a solvent. All synthesized compounds were evaluated for anticancer and antimicrobial activity in vitro. Amongst these, the 3-methylbutanoic and the 3-or 4-methylpentanoic acid derivatives, the 3-hydroxy-, the 3-(1H-imidazol-4-yl) and the 3-(4-hydroxyphenyl)propanoic acid derivatives and the succinic acid derivative showed high antibacterial and antifungal activity. The unsubstituted propanoic acid derivative exhibited significant antibacterial activity against B. subtilis and significant antifungal activity against fungal strains, i.e., A. flavus. The in vitro anticancer studies revealed that the 3-(hydroxy)-, the 3-(1H-imidazol-4yl)-and the 3-(4-hydroxyphenyl)propanoic acid, or the succinic acid derivatives are the most active compounds against MCF-7 and BT-474 human breast cancer cell lines.

A rapid, specific, sensitive, and precise reverse-phase HPLC method for the quantitative determination of process related and degradation impurities of Apixaban, an anticoagulant drug is described. The developed RP-HPLC method was successfully applied to the analysis of both Apixaban drug substance and drug product. The chromatographic separation was achieved on a Sigma-Aldrich's Ascentis Express ® C18 (4.6 mm × 100 mm, 2.7 µ) HPLC column with a runtime of 40 min. Mobile phase-A and mobile phase-B were phosphate buffer and acetonitrile respectively. The column oven temperature was set at 35˚C and photodiode array detector was set at 225 nm. Nine process related impurities (Imp-1 to Imp-9) have been detected in test sample of Apixaban by using newly developed RP-HPLC method. Forced degradation study was carried out under acidic, alkaline, oxidative, photolytic and thermal conditions to demonstrate the stability-indicating nature of the developed RP-HPLC method. The developed method was validated as per ICH guideline and found to be specific, precise, sensitive and robust.

Described is a simple, rapid, selective, and stability-indicating RP-LC method for the determination of process and degradation-related impurities of bosentan monohydrate. Chromatographic separation was achieved on Zorbax SB-Phenyl column thermostated at 35°C under gradient elution by a binary mixture of solvent A (60% phosphate buffer, pH 2.5, and 40% methanol) and solvent B (acetonitrile) at a flow rate of 1.0 mL/min. Forced degradation was carried out under acidic, alkaline, oxidative, photolytic, and thermal conditions. Significant degradation is observed in acid and alkali stress conditions. Process- and degradation-related impurities were characterized by mass spectrometry, 1H NMR, and FT-IR spectral data. Validation of the developed method was carried out as per ICH requirements. Regression analysis shows an “r” value (correlation coefficient) of greater than 0.999 for bosentan and five potential impurities. This method was capable to detect the five impurities at 0.01% of the test concentration of 1.0 mg mL-1.

A stability-indicating method has been developed and validated for the quantitative determination of memantine hydrochloride and its nonchromophoric impurities in drug substance and drug product using gas chromatography coupled with flame ionization detector (GC-FID). The stability-indicating nature of the method has been proved by establishing peak purity and confirming the mass balance of all samples by subjecting them to stress conditions like hydrolysis, oxidation, photolysis, and thermal degradation studies. The chromatographic separation was performed on a fused silica capillary (HP-5, 30 meter, 0.32 mm and 0.25 μm film thickness) column. The method validation results indicate that the method has acceptable specificity, accuracy, linearity, precision, robustness, and high sensitivity with detection limits and quantitation limits ranging from 0.001% to 0.01% and 0.004% to 0.03%, respectively. The effectiveness of the technique was demonstrated by analysis of different bulk sample of Memantine hydrochloride. The proposed GC-FID method was also found to be specific and selective for the analysis of commercial formulation samples.

Microwave assisted and conventional synthetic methods of new 6-bromo-2-(substituted)-3H-imidazo [4,5-b]pyridine and its derivatives are described, which were obtained in reduced reaction times, higher yields, cleaner reactions than previously described methods. All the synthesized compounds were characterized, and screened for their anticancer and antimicrobial activity. Among synthesized compounds 3b and 3k shows prominent antibacterial activity and compound 3f shows both antibacterial and antifungal activity. Compounds 3h and 3j shows prominent anticancer activity against the both breast cancer cell lines, MCF-7 and BT-474. These results suggest that the imidazo [4,5-b]pyridine moiety may serve as a new promising template for synthesis of anticancer and antimicrobial agents and further study is required for evaluation of their mechanism of action.