Y. L. N. Murthy

A New Rapid and Sensitive Stability-Indicating UPLC Assay Method for Tolterodine Tartrate: Application in Pharmaceuticals, Human Plasma and Urine Samples.

A new rapid, simple, sensitive, selective and accurate reversed-phase stability-indicating Ultra Performance Liquid Chromatography (RP-UPLC) technique was developed for the assay of Tolterodine Tartrate in pharmaceutical dosage form, human plasma and urine samples. The developed UPLC method is superior in technology to conventional HPLC with respect to speed, solvent consumption, resolution and cost of analysis. Chromatographic run time was 6 min in reversed-phase mode and ultraviolet detection was carried out at 220 nm for quantification. Efficient separation was achieved for all the degradants of Tolterodine Tartrate on BEH C18 sub-2-μm Acquity UPLC column using Trifluoroacetic acid and acetonitrile as organic solvent in a linear gradient program. The active pharmaceutical ingredient was extracted from tablet dosage form using a mixture of acetonitrile and water as diluent. The calibration graphs were linear and the method showed excellent recoveries for bulk and tablet dosage form. The test solution was found to be stable for 40 days when stored in the refrigerator between 2 and 8 °C. The developed UPLC method was validated and meets the requirements delineated by the International Conference on Harmonization (ICH) guidelines with respect to linearity, accuracy, precision, specificity and robustness. The intra-day and inter-day variation was found be less than 1%. The method was reproducible and selective for the estimation of Tolterodine Tartrate. Because the method could effectively separate the drug from its degradation products, it can be employed as a stability-indicating one.

Synthesis, characterization, and antimicrobial activity of some new 2-diazo-benzimidazole derivatives and their Ni(II), Cu(II), and Ag(I) complexes

Abstract2-Aminobenzimidazole was diazotized and made to react with active methylene compounds viz: ethylcyanoacetate and malanonitrile. The ligands [IIIa and IIIb] were isolated, characterized, and then condensed with Ni(II) chloride, Cu(II) chloride, and Ag(I) nitrate. The ligands and complexes were characterized by elemental analysis, IR, 1H NMR, ESR, UV–Visible spectral techniques, and along with thermal studies. The antimicrobial activity of the ligands [IIIa (C12H11N5O2) and IIIb (C10H6N6)] and their metal complexes [IVa–IVf] against bacterial strains and fungal strains were investigated. The antimicrobial activity of the above metals and the ligands were discussed.

Nano copper ferrite: A reusable catalyst for the synthesis of β , γ -unsaturated ketones

AbstractCopper ferrite nano material as reusable heterogeneous initiator in the synthesis of β, γ-unsaturated ketones and allylation to acid chlorides are presented. The reaction of allylichalides with various acid chlorides is achieved in the presence of copper ferrite nano powders at room temperature in tetrahydrofuran (THF). The present method is first of its kind in the synthesis of title compounds without any additive/ co-catalyst. The nano catalyst is easily recovered and its reusability is recorded. Graphical AbstractAn efficient protocol for the synthesis of β, γ -unsaturated ketones using copper ferrite nano material was achieved. The compounds were characterized by spectroscopic techniques.

Microwave-assisted neat reaction technology for regioselective thiocyanation of substituted anilines and indoles in solid media

An efficient and solvent -free approach for regioselective thiocyanation of various substituted anilines and indoles is described. The reaction performed both on and off the alumina surface under microwave conditions. Microwave irradiation reactions under solvent-free conditions resulted in a “green-chemistry” procedure, by which thiocyanation was achieved. In comparison to other reported methods for regioselective thiocyanation of anilines and indoles on the focus of reaction times, yields and usage of oxidizing agents, the present method shows considerable advantages.

Rapid synthesis, characterization, anticancer and antimicrobial activity studies of substituted thiadiazoles and their dinucleating ligand metal complexes

Synthesis of 2,5-disubstituted thiadiazoles was accomplished via a conventional method as well as microwave irradiation method. These substituted thiadiazoles were diazotized and coupled with 2,4-pentanedione (AcAc), ethylcyanoacetate (ECA) and malanodinitrile (MN) to get dinucleating ligands. The ligands were isolated, characterized and condensed with Ni (II), Cu (II) and Ru(III) chlorides. These compounds were screened on HL-60 Human leukemia cell Line and U-937 Lymphoma cell lines for anticancer activities. The antimicrobial activity of the ligands and their complexes against bacteria and fungi was also investigated. The effect of metal on the ligand activity is discussed.

Synthesis and bioevaluation of Schiff and Mannich bases of isatin derivatives with 4-amino-5-benzyl-2,4-dihydro-3H-1,2,4-triazole-3-thione

Isatin (2,3-dioxindole) and its derivatives show a wide range of biological activities. In the present study, a series of Schiff and Mannich bases of isatin derivatives were prepared using 4-amino-5-benzyl-2,4-dihydro-3H-1,2,4-triazole-3-thione. The structures of these derivatives were characterized by IR, 1H NMR and elemental analysis. In vitro antimicrobial activities were evaluated by agar dilution method and the zone of inhibition values of these derivatives were compared with ciprofloxacin and fluconazole. Chloro and Bromo groups at fifth position of isatin broaden the spectrum of antibacterial activity against S. aures, P. aeruginoa, and E. coli, respectively. For the antifungal activity, the compound 6h showed equipotent activity against A. niger. The remaining majority of the compounds were found active in the biological screening. The efforts were also made to establish structure activity relationships among synthesized compounds.

Antimicrobial evaluation of 1,4-benzoxazine derivatives

In this study, a series of N-unprotected 1,4-benzoxazine derivatives were evaluated for antibacterial activity. All the compounds showed low to good activity against Gram-positive and Gram-negative bacteria. Benzoxazine derivatives bearing nitro and trifluoromethyl groups are more potent than the other ones. Compounds with cyanide and ester groups have displayed poor activity. The compound 1c has shown good activity against Gram-positive as well as Gram-negative bacteria.

UPLC Method for Simultaneous Separation and Estimation of Secnidazole, Fluconazole and Azithromycin in Pharmaceutical Dosage Forms

A novel approach was carried out to develop and validate a rapid, specific, accurate and precise reverse phase ultra performance liquid chromatographic (UPLC) method for the simultaneous separation and quantification of secnidazole, fluconazole and azithromycin in pharmaceutical dosage forms. The developed analytical method is superior in technology to conventional HPLC with respect to time, resolution, solvent consumption and cost of analysis. Elution time for the separation was 10 min and ultra violet detection was carried out at 210 nm. Efficient separation was achieved on BEH C18 sub-2-μm UPLC column using 0.002 M Na2HPO4 and acetonitrile as organic solvent in a gradient program. Benzophenone was used as internal standard. Resolutions between secnidazole, fluconazole and azithromycin were found to be more than 4.8. The calibration graphs were linear for secnidazole, fluconazole, benzophenone and azithromycin. The method showed excellent recoveries for all dosage forms. The test solution was found to be stable in diluent for 72 h when stored in the refrigerator between 2 to 8 °C. The proposed UPLC method was validated with respect to linearity, accuracy, precision, specificity and robustness and can be used for the simultaneous estimation of secnidazole, fluconazole and azithromycin in tablet dosage forms available as a combi kit.

Synthesis, X-ray characterization and biological evaluation of some new 2-(4-methy-2-oxo-2H-chromen-7yloxy) acetamide derivatives

Newly designed coumarinyloxy acetamide derivatives (7a–7n) were synthesized in good yields and characterised by advanced spectroscopic studies and the XRD studies indicated that no polymorphism is observed in the molecules. Synthesized coumarinyloxy acetamides showed potent antimicrobial activity on human pathogens. Some of the analogues were found to have comparable or even more potency than the standard drugs (Ciprofloxacin for bacteria and Griseofulvin for dermatophytic fungi). Aromatic coumarinyloxy amides possess good antimicrobial activity followed by alicyclic compounds but aliphatic straight chain coumarinyloxy amides showed poor antimicrobial activity. In vitro results were correlated with docking studies.

Efficient synthesis of lactonic and thionolactoniclignans and evaluation of their anti-oxidant, anti-inflammatory and cytotoxic activities

A short and versatile synthesis of α,β-dibenzyl-γ-butyrolactones has been developed starting from inexpensive materials by applying Stobbe condensation and following the novel reductive cyclisation with sodiumborohydride. Natural products Suchilactone (5a), Kaerophyllin (5b), savinin (5d) and anhydropodorhizol (5f) were prepared in racemic form. New thionolactones (6a–6e) were prepared by treating these lignans with Lawesson’s reagent. For all the prepared compounds the antioxidant, anti-inflammatory (5-lipoxygenase inhibition) and cytotoxic (Brine shrimp lethality test) activities were tested. The compounds 5a, 5b, 5c, 5d, 5e and 5f showed good 5-lipoxygenase inhibition activity. The thiono lignan 6d showed impressive cytotoxic activity.