Design, synthesis, and biological evaluation of N-arylpiperazine derivatives as interferon inducers.

Type I Interferon (IFN) signaling plays an important role in the immune defense system against virus infection and in the innate immune response, thus IFNs are widely used as anti-viral agents and treatment for immune disorder or cancer. However, there is a growing demand for novel small-molecule IFN inducer due to tolerance, toxicity, or short duration of action following direct administration of IFNs. In this study, we assessed arylpiperazine (ARP) as a new core skeleton of IFN inducer. To investigate structure-activity relationship, we designed and synthesized a series of ARP analogues and evaluated the ability to stimulate IFN response in THP-1 human monocyte cells. Compound 5i was identified as a potent type I IFN inducer as it significantly increased cytokine secretion and increased expression of various IFN-stimulating genes which are representative biomarkers of type I IFN pathway. Our results suggested a beneficial therapeutic potential of 5i as an anti-viral agent.

Synthesis, DNA binding and in-vitro cytotoxicity studies on novel bis-pyrazoles.

A new series of bis-pyrazoles 6a-t were synthesized from 3,5-dimethyl pyrazole using sequential approach. All these compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral data. The interaction of newly synthesized bis-pyrazoles with DNA was investigated through molecular docking and absorption spectroscopic technique. Among all bis-pyrazoles compounds, the 6h compound showed lower conformational energy through in silico analysis. The interaction of each molecule in this series 6a-t with the various concentrations of DNA was examined through the UV-visible spectroscopic studies. The UV-visible spectroscopy studies on the specific binding of compound 6a, 6b, 6g, 6h, 6d, 6i, 6k, 6n, 6s with DNA have exhibited spectral shifts and the results were discussed. In further the compounds 6a-t were subjected to the in-vitro cytotoxicity studies against human pancreatic adenocarcinoma, human non-small cell lung carcinoma cell lines. Among the screened compounds, N-(3-isopropoxy-1-isopropyl-4-(3,5-dimethyl-1H-pyrazol-1-yl)-1H-pyrazol-5-yl)cyclobutane carboxamide and N-(5'-Isopropoxy-2'-isopropyl-3,5-dimethyl-2'H-[1,4'] bipyrazolyl-3'-yl)-dimethane sulfonamide were found as lead molecules since they have exhibited promising activity against both the cancer cell lines used in this study, whereas the compounds 4-(trifluoromethyl)-N-(3-isopropoxy-1-isopropyl-4-(3,5-dimethyl-2H-pyrrol-2-yl)-1H-pyrazol-5-yl)benzamide and 2,6-difluoro-N-(3-isopropoxy-1-isopropyl-4-(3,5-dimethyl-2H-pyrrol-2-yl)-1H-pyrazol-5-yl) benzamide were found to be active against the pancreatic cell line only. Rest all the other compounds were found to exhibit moderate to good activity towards both the cell lines.

A validated RP-HPLC method for the determination of Irinotecan hydrochloride residues for cleaning validation in production area / Método RP- HPLC validado para la determinación de residuos de Irinotecan Hidrocloruro para la validación de la limpieza en el área de producción

Introduction: cleaning validation is an integral part of current good manufacturing practices in pharmaceutical industry. The main purpose of cleaning validation is to prove the effectiveness and consistency of cleaning in a given pharmaceutical production equipment to prevent cross contamination and adulteration of drug product with other active ingredient. Objective: a rapid, sensitive and specific reverse phase HPLC method was developed and validated for the quantitative determination of irinotecan hydrochloride in cleaning validation swab samples. Method: the method was validated using waters symmetry shield RP-18 (250mm x 4.6mm) 5 µm column with isocratic mobile phase containing a mixture of 0.02 M potassium di-hydrogen ortho-phosphate, pH adjusted to 3.5 with ortho-phosphoric acid, methanol and acetonitrile (60:20:20 v/v/v). The flow rate of mobile phase was 1.0 mL/min with column temperature of 25°C and detection wavelength at 220nm. The sample injection volume was 100 µl. Results: the calibration curve was linear over a concentration range from 0.024 to 0.143 µg/mL with a correlation coefficient of 0.997. The intra-day and inter-day precision expressed as relative standard deviation were below 3.2%. The recoveries obtained from stainless steel, PCGI, epoxy, glass and decron cloth surfaces were more than 85% and there was no interference from the cotton swab. The detection limit (DL) and quantitation limit (QL) were 0.008 and 0.023 µg ml-1, respectively. Conclusion: the developed method was validated with respect to specificity, linearity, limit of detection and quantification, accuracy, precision and solution stability. The overall procedure can be used as part of a cleaning validation program in pharmaceutical manufacture of irinotecan hydrochloride.

Development and validation of a stability-indicating RP-HPLC method for the simultaneous estimation of process related impurities and degradation products of rasagiline mesylate in pharmaceutical formulation.

A sensitive, stability-indicating gradient reverse phase high-performance liquid chromatography-ultraviolet method has been developed for the quantitative determination of process-related impurities and forced degradation products of rasagiline mesylate in pharmaceutical formulation. Efficient chromatographic separation was achieved on an ACE C8, 150 × 4.6 mm, 3 µm column with mobile phase containing a gradient mixture of solvents A and B. The flow rate of the mobile phase was 0.8 mL/min with column temperature of 30°C and detection wavelength at 210 nm. Rasagiline was subjected to the stress conditions of oxidative, acid, base, hydrolytic, thermal and photolytic degradation. Rasagiline was found to degrade significantly in acid and thermal stress conditions. The degradation products were well resolved from rasagiline and its impurities. The peak purity test results confirmed that the rasagiline peak was homogenous and pure in all stress samples and the mass balance was found to be more than 97%, thus proving the stability-indicating power of the method. The developed method was validated according to the guidelines of the International Conference on Harmonization with respect to specificity, linearity, limits of detection and quantification, accuracy, precision and robustness.

A validated stability-indicating LC method for acetazolamide in the presence of degradation products and its process-related impurities.

The objective of the current study was to develop a validated, specific and stability-indicating reverse phase liquid chromatographic method for the quantitative determination of acetazolamide and its related substances. The determination was done for an active pharmaceutical ingredient, its pharmaceutical dosage form in the presence of degradation products, and its process-related impurities. The drug was subjected to stress conditions of hydrolysis (acid and base), oxidation, photolysis and thermal degradation as per International Conference on Harmonization (ICH) prescribed stress conditions to show the stability-indicating power of the method. Significant degradation was observed during acid and base hydrolysis, and the major degradant was identified by LC-MS, FTIR and (1)H/(13)C NMR spectral analysis. The chromatographic conditions were optimized using an impurity-spiked solution and the generated samples were used for forced degradation studies. In the developed HPLC method, the resolution between acetazolamide and, its process-related impurities (namely imp-1, imp-2, imp-3, imp-4 and its degradation products) was found to be greater than 2. The chromatographic separation was achieved on a C18, 250mmx4.6mm, 5microm column. The LC method employed a linear gradient elution, and the detection wavelength was set at 254nm. The stress samples were assayed against a qualified reference standard and the mass balance was found to be close to 99.6%. The developed RP-LC method was validated with respect to linearity, accuracy, precision and robustness.