Revealing analgesic and anxiolytic potentials of synthetic benzimidazole analogues: An in-vivo and in-silico study.

Certain drugs have potential to affect and alter individual's behavior. On the other hand, pain is a complex phenomenon with various treatment options; analgesic medicines are the primary source. Therefore, this study was based on examining some of the benzimidazole analogues for their analgesic as well as behavioral potential following Tail immersion test and Open field test respectively. In addition, molecular docking was performed to find the interaction of these compounds with the active site using AutoDock Vina which was further visualized through Discovery Studio Visualizer. It was seen that the cyano-methyl benzimidazole derivatives (CMB1-CMB3) showed relief in pain as compared to benzimidazole derivatives (BI1-BI3), CMB2 demonstrated highly potent analgesic effect. Likewise, all structures except BI1 displayed increase locomotion during open field test and can be offered as anxiolytic compounds. Almost all derivatives showed improve binding energies for the tested proteins where the high analgesic action of CMB2 might be correlated to its high binding affinity and interaction at µOR. It was also noticed that all structures except BI showed possible binding interaction with GABAA receptor and hence possessed anxiolytic like potential. Thus, this study offered benzimidazole analogues for further drug development of analgesic and anxiolytic like compounds.

The in vitro study of interaction between antacids and anti-diabetic drug sitagliptin in the treatment of type II diabetes.

Hyperglycemia is a long-lasting syndrome that occurs either when the pancreas cannot produce enough insulin, or the body cannot effectively utilize that insulin to regulate blood sugar levels. Non-insulin-dependent hyperglycemia, also known as type II diabetes, causes a common consequence of severe damage to many of the body's organs mainly the blood vessels and nerves. The majority of people around the world are suffering from non-insulin-dependent diabetes. The present work showed a great effort to investigate any possible interaction between antacids and sitagliptin (anti-diabetic drug) in the treatment of type II diabetes with gastrointestinal tract problems. The in vitro studies were carried out in simulated gastric juice pH 2.0 and intestinal pH 7.4 at 37oC. MgCO3, NaHCO3, Mg(OH)2, Al(OH)3 and CaCO3 were used as antacids in these studies. It has been observed that % release of sitagliptin was significantly enhanced in the presence of calcium carbonate and magnesium carbonates.

The LC-QTOF-MS/MS analysis of acid degradation products of Rifaximin, an antibiotic.

The present research aims to propose a simple and accurate technique for the analysis of Rifaximin in the presence of its stress degradation products and analysis of degradation products by LC-MS/MS analysis. Rifaximin was submitted to forced degradation under the acid hydrolysis condition as prescribed by the ICH. The extract was prepared by firstly treated with HCl and heated about 4 to 8 h. The filtrate was collected and separated using dichloromethane followed by evaporation in rotary evaporator to obtain a solid crude extract which was then stored under refrigeration at -80 °C. Liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS/MS) was utilized to identify products in the drug sample. The data processing results revealed the presence of 9 products in the degraded sample of Rifaximin. This data article contains the m/z [M + H +] values, molecular formula, retention times and the comprehensive list of m/z values detected during the LC- QTOF- MS/MS analysis.

Development and validation of RP-HPLC method for simultaneous determination of cefpodoxime proxetil and H2 receptor antagonists in pharmaceutical dosage forms.

A new method on RP-HPLC is devised and validated, as per ICH guidelines, for the synchronous estimation of cefpodoxime proxetil and H2-receptor antagonits that are Cimetidine, Famotidine and Ranitidine. The method is simple, accurate, expeditious, reproducible, robust and precise. Chromatography was done on a C18 (250 x 4.6mm) column with methanol: water as mobile phae in the ratio of 70:30 (v/v), pumped at a flow rate of 1ml/min and pH was maintained using 85% ortho-phosphoric acid at 3. The λ max 240 nm was preferred for UV detection. A good linear relationship was attained, over the concentration ranges of 20-70 µg/ml and 5-30µg/ml, for cefpodoxime proxetil and H2 blockers respectively, with a correlation coefficient of R= 0.9987 to 0.9992. The method was validated and found precised (i.e. intra day and interday analysis) with RSD <2%. LOD and LOQ observations were under 0.4806 to 2.6069µg/ml which proved the method to be sensitive. The method provided satisfactory results of robustness and reproducibility, when validated and applied successfully for analysis of dosage forms.

Anti-Oxidant and digestive enzymes inhibitory based anti diabetic activity of crude and fractions of Carum carvi L. extracts.

In the present study crude ethanolic extract and its various fractions (ethyl acetate, hexane and aqueous) of medicinal plant Carum carvi L. were examined for α-amylase and α-glucosidase inhibition using an-in vitro model. Both digestive enzymes were extracted from bovine and green gram. The crude extract and its fractions were also studied for their antioxidant potential by DPPH and Nitric oxide activity. The quantitative assessment of phenol and flavonoid contents was also estimated. The crude extract and its fractions exhibited high in-vitro enzyme inhibitory activity against α-amylase and α-glucosidase at different concentrations with IC50 ranging from 421.4±7.8 to 810±5.71and 72±8.81 to 307.0±11.42µg/mL of each extract respectively. The plant showed highest total phenolic contents ranging from 29.5±0.49 to 112.5±0.36mg/g Gallic acid of extract, while the total flavonoid contents were estimated from3.08±0.02-85.4± 0.12mg/g Quercetin. The antioxidant activities of the all extracts, measured in terms of IC50 values were in the range of 53.05±1.98 to 211.5±31.06µg/mL. Nitric oxide scavenging ability exhibited their IC50 values from 26.3±5.51 to 121.3±5.32µg/mL. Ethanolic crude extract showed excellent result among all these fractions. GCMS analysis of ethanolic extract of Carum carvi L indicated the presence of several phytochemicals such as monoterpenes, unsaturated fatty acids, furan derivatives, phenolic and flavonoid contents.

Development and validation of HPLC method for the determination of Candesartan in human plasma.

Candesartan (CAN), an ARB-blocker, antihypertensive, was analyzed in human plasma by a simple, accurate and precise RP-HPLC (reverse phase-High performance liquid chromatography assay method which was then validated for its accuracy, specificity and precision. The mobile phase has a constitution of acetone, diethylamine and distilled water, while Phosphoric acid was used to adjust the pH to 2.5±0.1. This mobile phase was run at 1.1ml/min and the fluorescence wavelength was set to 392 nm. A C-18 HPLC, column particle size (5 µm) Mediterranean Sea ® L x 1.D. 25cm x 4.6 mm (Supelcosil) , with auto sampler injection volume of 30µl ,an internal standard Valsartan was utilized for chromatographic detection. Candesartan took a retention time of 6±0.5 minutes. This method was validated by the parameters of selectivity, accuracy, precision, repeatability, reproducibility, recovery, linearity and stability. Candesartan's calibration curves were found to be linear in the range of 200ng/ml to 3.125ng/ml and the coefficient of determination (r2) was found to be 0.99. Analytical recovery obtained was above 88%. Hence, this method has been found to be useful for determining Candesartan in plasma.

Determination of pKa values of new phenacyl-piperidine derivatives by potentiometric titration method in aqueous medium at room temperature (25±0.5oC).

Dissociation constant (pKa) of ten novel phenacyl derivatives of piperidine were determined by potentiometric titration method in aqueous medium at room temperature (25 ±0.5°C). The sample solutions were prepared in deionized water with ionic strength 0.01M and titrated with 0.1M NaOH solution. In addition, ΔG values were also calculated. Different prediction software programs were used to calculate pKa values too and compared to the experimentally observed pKa values. The experimental and theoretical values were found in close agreement. The results obtained in this research would help to predict the good absorption of the studied compounds and can be selected as lead molecules for the synthesis of CNS active agents because of their lipophilic nature especially compound VII.

Behavioral and neurochemical profile of some novel phenacyl based isonipecotamide derivatives.

Study of natural products led to the development of new molecules of potential biological activity. Piperidine nucleus constitutes one of the components of various alkaloids and drugs. During the course of our project regarding the synthesis of derivatives of piperidine carboxamide to study the effects of these compounds as anti-depressive agents, some of the compounds exhibited significant effects at all three doses, through open field activity thus establishing a direct relationship between dose and locomotion. Moreover, these compounds have also shown the decreased level of 5-HT alone with increased level of dopamine as an indication of their antagonism towards 5-HT receptor.

New benzimidazole derivatives as antiplasmodial agents and plasmepsin inhibitors: synthesis and analysis of structure-activity relationships.

The newly synthesized benzimidazole compounds were suggested to be inhibitors of Plasmodium falciparum plasmepsin II and human cathepsin D by virtual screening of an internal library of synthetic compounds. This was confirmed by enzyme inhibition studies that gave IC(50) values in the low micromolar range (2-48µM). Ligand docking studies with plasmepsin II predicted binding of benzimidazole compounds at the center of the extended substrate-binding cleft. According to the plausible mode of binding, the pyridine ring of benzimidazole compounds interacted with S1' subsite residues whereas the acetophenone moiety was in contact with S1-S3 subsites of plasmepsin II active center. The benzimidazole derivatives were evaluated for capacity to inhibit the growth of intraerythrocytic P. falciparum in culture. Four benzimidazole compounds inhibited parasite growth at ⩽3µM. The most active compound 10, 1-(4-phenylphenyl)-2[2-(pyridinyl-2-yl)-1,3-benzdiazol-1-yl]ethanone showed an IC(50) of 160nM. The substitution of a phenyl group and a chlorine atom at the para position of the acetophenone moiety were shown to be crucial for antiplasmodial activity.