Search

The most important nitrogen containing heterocycles of pyridine containing substituted phenyl azetidine-2-ones have found pharmacological application such as antibiotics and these compounds also have practical importance. The structure of the new derivatives was confirmed by the spectral data and elemental analyses. Out of five new derivatives, three were revealed mild to moderate activity compared with Streptomycin & Fluconazole as a reference standard. Among this new series, 3-chloro-1-(4-fluoro phenyl)/(4-chloro phe-nyl)-4-(pyridine-3-yl) azetidine-2-one (4a & b) were found most activity.

A new class of pyrimido pyrimidine derivatives that exhibits in vitro antimicrobial activity was synthesized. The protection of amino group in the compound 1 with acetic anhydride, followed by the reaction with POCl3, gave 3. The reaction of 3 with different substituted phenyl methanediamine in dry TEA under inert atmosphere led to the formation of 4. Deprotection of 4 followed by refluxion with different acid chlorides yielded title compounds 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m in good yields. The identities of these compounds were confirmed following elemental analysis, IR, 1H, 13C NMR, and mass spectral studies. All the title compounds exhibited pronounced in vitro antibacterial and antifungal activities.

A novel, selective and sensitive reverse phase-high performance liquid chromatography (RP-HPLC) method has been developed for the validated estimation of imidazol-1-yl-acetic acid in zoledronic acid formulations. The separation was achieved on a 5 μ C18 column (250 × 4.6 mm) using a mobile phase that consists of the buffer (4.5 g of di-potassium hydrogen phosphate anhydrous and 2.0 g of tetra butyl ammonium hydrogen sulphate (TBAHS) in 1000 mL of water) and methanol in the ratio of 900:100 v/v. The flow rate was maintained at 1.0 mL min −1 . The detection of the constituents was done at 215 nm using a UV detector. The retention times of imidazol-1-yl-acetic acid and zoledronic acid were 7.2 and 10.2 min respectively. Recovery studies were satisfactory and the correlation coefficient, 0.999 indicates linearity of the method within the limits. The developed method can be applicable for regular qualitative analysis.

A rapid and simple Spectrophotmetric method has been developed for the determination of microgram amount of Chromium (VI) in aqueous dimethyl formamide (DMF). Chromium (VI) forms a yellowish green coloured M:L complex with 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone in the acidic buffer medium (pH=6.0) at room temperature. The complex shows maximum absorption at 385nm. Beer's law is obeyed in the range 0.260 to 2.60 

A chromophoric reagent, 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC), was employed for the sensitive spectrophotometric determination of gold(III). The gold(III) ion forms a blue-coloured complex with HMBATSC in an aqueous dimethyl formamide at pH 6.0. The gold complex shows the absorption maximum at 385 nm, and Beer's law was obeyed in the range 0.49–8.37 μg mL−1. The molar absorptivity and Sandell's sensitivity were found to be L mol−1 cm−1 and 0.015 μg cm−2, respectively. The complex shows 1 : 1 [Au(III) : HMBATSC] stoichiometry with a stability constant of . The interference effect of various diverse ions has been studied. In addition to zero-order, first- and second-order derivative spectrophotometric methods were also developed for the determination of gold(III) in microgram amounts which were more sensitive than the zero-order method. The developed method has been used for the determination of gold(III) in environmental water samples and certified reference materials. The results were in excellent agreement with the certified values.

A chromatographic method was established for the determination of lenalidomide and related substances in 10 mg and 5 mg capsules using Sunfire C-18(250×4.6 mm ID, 5 μm) HPCL column with 85:15 v/v ratio of mobile phases A (mixture of phosphoric acid buffer and 1-octane sulphonic acid sodium salt) and B(55: 45 v/v ratio of methanol and acetonitrile) at 40°C and 210 nm wave length. The degradation studies were performed using 0.1N HCl, 0.1 N NaOH, 1% v/v hydrogen peroxide, humidity, UV at 254 nm, Sun light, and heat to 60°C. No significant degradation of lenalidomide was observed. However, the slight degradation was observed in presence of NaOH. The developed HPLC method gave the peaks purity angle was less their threshold angle, indicating it to be suitable for stability studies. It was validated with respect to linearity, accuracy, precision, ruggedness, and robustness.

A simple, sensitive, and selective second-order-derivative spectrophotometric method has been developed for the simultaneous determination of palladium(II) and ruthenium(III) using 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) as a chromophoric reagent. The reagent (HMBATSC) reacts with Pd(II) and Ru(III) at pH 3.0, forming soluble yellowish green and dark brown species, respectively. Palladium and ruthenium present in the mixture were simultaneously determined without solving the simultaneous equations by measuring the second derivative amplitudes at 445 nm and 385 nm, respectively. Further, the Beer's law was obeyed in the range 0.21–12.78 µg mL−1 and 0.25–13.42 µg mL−1 for Pd(II) and Ru(III), respectively. A large number of foreign ions did not interfere in the present method. The proposed method was successfully applied for the determination of palladium in hydrogenation catalysts and ruthenium in water samples.

A rapid and sensitive spectrophotometric method is developed for the determination of Copper (II) in aqueous DMF medium. The metal ion forms a light greenish yellow coloured complex with 5-bromo salicylaldehyde thiosemicar- bazone (5-BSAT) in acidic medium. The complex shows absorption maximum at 390nm. Beer's law is obeyed in the range 0.31 - 6.35 � gml -1 of Copper (II). The molar absorptivity (� ) and Sandell's sensitivity are found to be 1.08 X 10 4 l mole -1 cm -1 and 0.062 � gcm -2 respectively. A method for the determination of copper by third derivative spectrophotome- try is also proposed. The methods have been employed successfully for the determination of copper in grape leaves and aluminum based alloy samples.

A highly sensitive and selective kinetic spectrophotometric method is proposed for the determination of silver in nanogram quantities. The method is based on catalytic activity of silver(I) in enhancing the green colour formation between potassium ferrocyanide and 2,4,6-tripyridyl-1,3,5-triazine (TPTZ) which is otherwise a very slow reaction at pH 2.0. The absorbance spectrum of the green coloured solution in presence of silver showed two peaks of almost equal intensity one at 405 nm and another at 600 nm. At both the wavelengths the absorbance of the experimental solution increased proportionally with the amount of silver(I) in the range 5 – 410 ng mL-1 and 10 – 610 ng mL-1 respectively. Other experimental conditions like pH, reagent concentration, ferrocyanide concentration and effect of time for obtaining maximum reaction rate were optimized. The molar absorptivity, Sandell's sensitivity, detection limit, determination limit and relative standard deviation (n = 8) were determined as 1.57 × 106 L mol-1 cm-1, 0.065 ng cm-2, 1.6 ng mL-1, 4.8 ng mL-1 and 0.81 % respectively. The effect of various diverse ions on the determination of silver was studied. The method was applied for the determination of silver in alloys, biological samples, effluents, real water and in ayurvedic medicines.

2-Hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) has been synthesized and its analytical applications are investigated. A rapid, simple, sensitive and selective spectrophotometric method is developed for the determination of palladium (II) in aqueous dimethyl formamide (DMF). Palladium (II) forms a yellowish green coloured M 2 L 3 complex with 2-hydroxy-3-methoxy-benzaldehyde thiosemicarbazone in the pH range 1.0-7.0 at room temperature. The complex shows absorption maximum at 380nm with molar absorptivity and Sandell's sensitivity of 2.198 x 10 4 l mol -1 cm -1 and 0.049μg cm -2 respectively. Beer's law is obeyed in the range of 0.426 to 4.257 μg ml -1 of Pd (II). A second order derivative spectrophotometric method for the determination of palladium (II) has also been proposed. Interference of various diverse ions has been studied. The proposed method is successfully applied for the determination of palladium in alloy steels and in hydrogenation catalysts.

A simple, sensitive, and selective second order derivative spectrophotometric method is proposed for the determination of microgram quantities of gallium(III) especially in presence of large excess of indium(III). Ga(III) reacts with 2‐hydroxy‐3‐methoxy benzaldehyde isonicotinoylhydrazone (HMBAINH) chromogene forming an intense greenish yellow coloured soluble complex in acidic buffers and in presence of 0.2% of triton X‐100. The complex showed maximum absorption at 405 nm and at pH 5.0, where the reagent has negligible absorbance. A second order derivative spectrum of the complex solution showed maximum derivative amplitude at 415 nm and again at 460 nm with a zero cross at 442 nm. Beer's law was obeyed in the concentration range 0.036–1.533 µg/ml and 0.070–1.533 µg/ml of Ga(III) at 415 nm and 460 nm, respectively. However, at 404 nm In(III)‐HMBAINH complex showed zero amplitude in the second order derivative spectrum where Ga(III)‐HMBAINH obeyed Beer's law in the range of 0.070–1.394 µg/ml. Thi...

A rapid, simple and sensitive spectrophotometric method was developed for the determination of cobalt(II) using 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) as a analytical reagent. The metal ion in aqueous medium forms a brown coloured complex with HMBATSC at pH 6.0. The complex has two absorption maxima at 375 nm and 390 nm. At 375 nm, the reagent shows considerable absorbance, while at 390 nm the reagent does not shows appreciable absorbance. Hence, analytical studies were carried out at 390 nm. Beer's law is obeyed in the range of 0.059-2.357 μg ml -1 of Co(II). The molar absorptivity and Sandall's sensitivity of the method are 2.74×10 4 mol -1 cm -1 and 0.0024 μg cm -2 respectively. The interference of various diverse ions has been studied. The complex has 1:2 [Co(II)-HMBATSC] stoichiometry. A method for the determination of cobalt(II) by second order derivative spectrophotometry has also been proposed. The proposed methods were applied for the determination of cobalt(II) in alloy steels, vitamin B 12 and in some biological samples.

2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) has been synthesized, characterized and employed as a simple simultaneous second order derivative spectrophotometric method for the analysis of a three-component system containing cobalt(II) nickel(II) and vanadium(V) without separation. The reagent (HMBATSC) reacts with cobalt(II), nickel(II) and vanadium(V) at pH 6.0, forming soluble brown, yellow and green coloured species, respectively. Cobalt, nickel and vanadium present in the mixture are simultaneously determined without solving the simultaneous equations by measuring the second derivative amplitudes at 460 nm, 450 nm and 430 nm, respectively. Further, the derivative amplitudes obey Beer's law at 460 nm, 450 nm and 430 nm for Co(II), Ni(II) and V(V) in the range 0.059 – 3.535 μg ml−1, 0.058 – 3.425 μg ml−1 and 0.051 – 4.074 μg ml−1, respectively. A large number of additional ions did not interfere with the method. The simultaneous method can be applied for the determination of cobalt(II) ...

A simple and sensitive spectrophotometric method is developed for the determination of zinc in aqueous solutions. The metal ion forms a greenish-yellow colored complex with 2,4-dihydroxybenzaldehyde isonicotinoyl hydrazone (2,4-DHBINH) in the pH range of 4–10. The complex shows maximum absorbance at 390 nm and in the pH range of 6–8. Beer's law is obeyed in the range 0.10–1.50 µg/mL of Zn(II). The molar absorptivity and Sandell's sensitivity are 3.55 × 104 mol−1 cm−1 and 0.0016 µg/cm2, respectively. The composition of the complex is 1 : 1. The effect of interfering ions has been studied, and the method was applied to the determination of zinc(II) in potable water and pharmaceutical samples. A fast derivative spectrophotometry method is also proposed for the determination of zinc in the range 0.06–1.60 µg/mL, which is more sensitive than the zero order method.

A series of novel pyrrolidine sulfonamide derivatives were designed, synthesized and screened in silico for their β-gluscosidase inhibitory activity. The results showed that the pyrrolidine derivatives exhibited moderate inhibitory activity against human β-gluscosidases inhibitors. The structure-activity relationships were also briefly discussed. The studies indicated that compounds of Series B with imidazole sulfonyl group were the most potent inhibitors compared to the other compounds under investigation.

The members of the new class of pyrimido pyrimidine derivatives (I) display pronounced in vitro antibacterial and antifungal activities.

A rapid, simple, sensitive and selective spectrophotometric method is developed for the determination of molybdenum (VI) in aqueous dimethyl formamide (DMF). Molybdenum (VI) forms a yellow coloured complex with 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone in the pH range 1.0-6.0. The complex shows maximum absorbance at 375nm and in the pH range 1.0-2.0. However, at this wave length, the reagent shows considerable absorbance. At 385nm, the complex shows large absorbance while the reagent blank shows negligible absorbance. Hence, analytical studies are carried out at 385nm and at pH 1.5 against reagent blank. Beer's law is obeyed in the range 0.24-4.32 µg ml-1. The molar absorptivity and Sandell's sensitivity forthe coloured solution are found to be 2.3 x 10-4 1 mol-1 cm-1 and 0.0042 µg cm-2 respectively. The interference effect of various diverse ions has been studied. The complex shows 1:1 [Mo (VI): HMBATSC] stoichiometry with a stability constant 2.35 x 10(6). The standard deviation of the method in the determination of 2.396 µg ml-1 of Mo(VI) is calculated as ± 0.0012. A second order derivative spectroscopic method is developed for the determination of molybdenum(VI), which is more sensitive than the zero order method.. The developed method has been employed for the determination of molybdenum (VI) in food stuffs and in alloy steels. The results are in excellent agreement with the certified values

A simple and new simultaneous fourth derivative spectrophotometric method is proposed for the analysis of a two-component system containing cobalt(II) and nickel(II) without separation using 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) as a chromophoric reagent. The reagent reacts with cobalt(II) and nickel(II) at pH 6.0, forming soluble brown and yellow colored species, respectively. Cobalt(II) and nickel(II) present in the mixture are simultaneously determined without solving the simultaneous equations by measuring the fourth derivative amplitudes at 468.5 nm and 474.5 nm, respectively. The derivative amplitudes obey Beer's law at 468.5 nm and 474.5 nm for Co(II) and Ni(II) in the range 0.059–3.299μgmL-1and 0.058–3.285μgmL-1, respectively. A large number of foreign ions do not interfere in the present method. The present simultaneous method is used for the determination of micro amounts of cobalt in biological samples, nickel in plant samples, and in some alloy steels and soil sample.