ABSTRACT

The electronic structure of lactam-lactim tautomerism in methicillin and its geometry and conformation have been optimized and calculated usually considering an isolated molecule surrounded by vacuum in the gas phase by semi-empirical molecular orbital AM1 method. The mechanism of protonation in lactim tautomer of methicillin has been studied by comparison of the different positions of net charges at nitrogen atoms in the molecule. In this connection, the heats of formation (ΔHfo), dipole moment (μ), ionization potential (IP), full atomic charges and energies of frontier molecular orbitals (EHOMO and ELUMO) have been performed and discussed. The conformational analyses of mono- and di-protonated lactim tautomers and their stable conformations have also been performed.

Keywords: AM1, Lactam-lactim Tautomerism, Methicillin, Induction Effect, Frontier Molecular Orbital.

ABSTRACT

A specific, precise, linear, accurate, rugged, robust, and stability indicating isocratic reversed phase high-pressure liquid chromatography method has been developed and validated as per ICH guidelines for estimation of related substances of Diltiazem Hydrochloride Extended Release Capsules 120,180,240,300,360mg USP. It was performed on a Waters μBondapak C18 (10μ particles size) (300 mm × 3.9 mm) column using mobile phase containing Acetate buffer Acetonitrile and Methanol in ratio 500:250:250 v/v/v (pH 6.3 adjusted with 0.1 N sodium hydroxide solution in buffer) at the flow rate 1.6 ml/min. Detection was performed at 240 nm and a sharp peak was obtained for Diltiazem hydrochloride at a retention time at about 20 min. Linear regression analysis data for the calibration plot showed there was a good linear relationship between response and concentration in the range 0.5-18 μg/ml; the regression coefficient was 0.999. The detection (LOD) and quantification (LOQ) limits were 0.16 and 0.51μg/ml respectively and Desacetyl diltiazem hydrochloride at a retention time at about 14.3 min. Linear regression analysis data for the calibration plot showed there was a good linear relationship between response and concentration in the range 0.4-5.3 μg/ml; the regression coefficient was 0.999. The detection (LOD) and quantification (LOQ) limits were 0.13 and 0.41μg/ml respectively. The HPLC method for the determination of related substances of Diltiazem Hydrochloride Extended Release Capsules 120,180,240,300,360 mg USP was validated. The stress sample solutions were assayed against the qualified reference standard of Diltiazem hydrochloride and the mass balance in each case was close to 99.9%, confirming its stability-indication capacity. The method was found to be specific, precise, linear, accurate, rugged, stability indicating and suitable for its intended use. The developed HPLC method to determine the related substances and assay determination of Diltiazem hydrochloride can be used to evaluate the quality of regular production samples. It can be also used to test the stability samples of Diltiazem hydrochloride.

Keywords: Diltiazem Hydrochloride, Desacetyl diltiazem hydrochloride, ICH, validation.

A simple and cost effective spectrophotometric method was described for the determination of Imipenem in pure form and in pharmaceutical formulations. The method is based on the formation of colored chromogen when the drug reacts with ninhydrin and ascorbic acid in presence of a buffer having pH 5.0, prepared by a mixture of citric acid and NaOH solutions This method was applied for the determination of drug contents in pharmaceutical formulations and enabled the determination of the selected drug in microgram quantities (0.5 to 3.0 mL). No interferences were observed from excipients and the validity of the method was tested against reference method. The colored species has an absorption maximum at 560 nm for IMP and obeys beer’s law in the concentration range 2-12 μg/mL of IMP. The apparent molar absorptivity was 157x10-6 and sandell’s sensitivity was 7x10-2. The slope is 0.2157 ± 0.0035, the intercept of the equation of the regression line is 0.0021 ± 0.0064. The optimum experimental parameters for the reaction have been studied and the validity of the described procedure was assessed. Statistical analysis of the results has been carried out revealing high accuracy and good precision. The proposed method was successfully applied for the determination of IMP in pharmaceutical formulations.
Keywords: Imipenem, ninhydrin, Ascorbic acid, Buffer, Spectrophotometry.

ABSTRACT

Adulteration in food is normally present in its most crude form, prohibited substances are either added or partly or wholly substituted. In India normally the contamination/adulteration in food is done either for financial gain or due to carelessness and lack in proper hygienic condition of processing, storing, transportation and marketing. This ultimately results that the consumer is either cheated or often become victim of diseases. Such type of adulteration is quite common in developing countries or backward countries. However, adequate precautions taken by the consumer at the time of purchase of such products can make him alert to avoid procurements of such food. It is equally important for the consumer to know the common adulterants and their effect on health. So the present paper deals with the list of adulterants that are added to food items and herbs.

Keywords: Adulteration, Piper nigrum, Carthamus tinctorius, Carthamus tinctorius, Papaya.

ABSTRACT

Preliminary phytochemical screening and mineral contents of Nigella sativa (black caraway) seed were investigated. The dried ground matter (300g) was macerated with 80% methanol for five days, filtered and concentrated in vapour using a rotary evaporator. The extract concentrate was estimated to be 14.5 w/w. The methanolic extract were subjected to preliminary phytochemical analysis using standard procedures which indicate the presence of Saponins, Terpenoids, Flavonoids, Carbohydrates Anthraquinone, Alkaloids and Cardiac glycoside. While the result of the proximate contents indicates that the dry matter has the highest percentage of 98.4 %, crude fibre 35.0%, carbohydrate 33.31%, ether 24.0 %, crude protein 5.69 %, ash 2.0 % and moisture content 1.6 %. The elemental analysis using (AAS) reveal the presence of Na (1.96mg/l), K (3.40mg/l), Cr (0.01mg/l), Zn (1.97mg/L), Fe (1.01mg/l), Mn (18.40mg/l), Ca (22.30mg/l), P (17.00mg/l). These elements are found in low concentration whereas Pb and Cr were not detected.

Keywords: Element, Extract, Phytochemicals, Nigella, Blackcaraway.

ABSTRACT

The plant Psidium guajava has been subjected to proximate and elemental determination. Also preliminary phytochemical screening was carried us to ascertain the secondary metabolites such as flavonoid, carbohydrate, saponins, tannins, cardio glycoside and terpenoids present in the ethanolic extract of the plant. The proximate analysis show the percentage content of dry matter (97.1%), moisture (2.9%), crude protein (0.70%) fat, (1.0%) crude fibre, (22.0%) Ash (3.0%), carbohydrate, (73.3%). The elemental content was determined by Atomic absorption spectroscopy (AAS) reveal the presence of some element such as potassium (6.40mg/l), manganese (0.11mg/l), iron (0.23mg/l), zinc (0.70mg/l), phosphorus (4.70mg/l), cadmium (0.25mg/l), chromium (0.14mg/l). Lead and sodium are not detected. Content The stem bark of Psidium guajava has phytochemicals such flavonoid, carbohydrate, saponins, tannins, cardio glycoside, terpenoids. The presence in the carbohydrate, protein, fats and the mineral element indicate the nutritional benefit of the plant while the phytochemical found are implicated in having a lot of medicinal important.

Keywords: Psidium guajava, Tannins, Terpenoid.

ABSTRACT

In the present study the dried material of Vernonia schimperi (Syn. Vernonia abyssinica Sch. Bip. ex Walp.) was successively extracted with acetone and 96% ethanol. These extracts were further fractionated with different solvents and were analyzed for their phytoconstituents using standard protocols. From the study it was found that alkaloids and terpenoids are totally absent while the test for phenols found positive in all the fractions. Hexane fractions as well as acetonitrile fraction of one minute acetone extract showed the presence of glycosides. The sterols are only present in hexane fraction of one minute acetone extract. Most of the constituents are present in polar solvent fractions. Over all plant is rich in pharmaceutically important phytochemicals.

Keywords: Vernonia schimperi, Extract, Phytochemical screening.

ABSTRACT

In the present study N-{[5-(2,4-dichlorophenyl)-1,3,4-oxadiazol-2-yl]methyl}amine derivatives5(a-h) were synthesized and tested for invitro anticancer activity. Cyclisation of 2, 4-dichlorobenzohydrazide in chloroacetic acid and phosphorous oxy chloride gives 2-(chloromethyl)-5-(2,4-dichlorophenyl)-1,3,4-oxadiazole.This on reaction with various primary and secondary aliphatic or aromatic amines gives the title compounds. The anticancer activity of some of the prepared compounds was evaluated using three human tumour cell lines, representing cervic, liver and breast. The compounds tested were, in most of cases, selective towards liver cancer, where the most potent compound showed IC50 = 2.46 μg/ mL. The synthesized compounds were purified by column-chromatography and characterized by LCMS, TLC, IR, and 1HNMR spectral data. Three different cell lines are used for the present study namely (Hela, Hep-G2 and MCF7). Keywords: Hela, Phosphorus oxy chloride, Hep-G, Anticancer, Triethylamine, MCF7.

ABSTRACT

In the present study an intermolecular reductive Schiff base formation from nitroarenes and benzaldehydes to yield diarylimines is carried out in the presence of iron powder and dilute acid. In the present study new Schiff base compounds derived from 2 nitro pyridine with aldehyde derivatives. Schiff bases were characterized by IR, and 1H NMR spectroscopy. The Schiff base ligands have also been tested in vitro for their antibacterial activity. The experimental results suggest that Schiff base ligands are more potent in anti-bacterial activities.

Keywords: Schiff bases, 2 Nitro pyridine, Salicylaldehyde, 5 Bromo salicylaldehyde 5 Methoxy salicylaldehyde, Antibacterial activity.

ABSTRACT

Impurity profiling helps in detection, identification and quantification of various types of impurities as well as residual solvents in bulk drugs and in pharmaceutical formulations. It is a best way to characterize quality and stability of bulk drugs and pharmaceutical formulations. ICH instructs workable guidelines to drug developers and regional agencies on how to evaluate and control impurities in drug substances and drug products. Impurity profiling is the process of acquiring and evaluating data that establishes biological safety of an individual impurity. Identification of impurities is done by variety of Chromatographic and Spectroscopic techniques, either alone or in combination with other techniques. There are different methods for detecting and characterizing impurities with TLC, HPLC, HPTLC, AAS etc. As per International Conference on Harmonization guidelines, the Impurity may be defined as any component of new drug product that is not the drug substance or an excipient in drug product.

Keywords: Impurity Profiling, Guidelines, ICH, Organic Impurities, Inorganic Impurities Residual Solvents.