Synthesis of 10-(substituted phenylhydrazonoacetyl)phenothiazines as possible anticonvulsants

Some 10-(substituted phenylhydrazonoacetyl)phenothiazines were synthesized as possible anticonvulsants. These compounds were investigated for their anticonvulsant activity and inhibitory effects on the oxidation of pyruvic acid by rat brain homogenates.     

Carbon-13 nuclear magnetic resonance spectra of potent antimalarials: Primaquine and chloroquine

C¹³ Nmr chemical shits of primaquine and chloroquine are reported. The signals are assigned on the basis of substituent effects on benzene shifts, intensities, multiplicities in SFORI) and the comparison with structurally related compounds.     

Fourier transform 13C NMR analysis of benzodiazepines

The natural abundance carbon-13 nuclear magnetic resonance spectra of diazepam, clonazepam, flurazepam and chlordiazepoxide were recorded in suitable solvent using the Fourier transform technique on a JEOL FX-60 spectrometer. The relaxation time (T₁) of these compounds were also measured. The chemical shift of the various carbon resonances have been assigned on the basis of chemical shift theory, multiplicity generated in single-frequency off-resonance decoupled spectra, relaxation time and the chemical shifts of the model compounds.     

Carbon-13 nuclear magnetic resonance spectra of isoquinoline alkaloids

The ¹³C nmr ehemieal shifts of 1,2,3,4-tetrahydroisoquinoline, salsolidine and laudanosine are reported. The various carbon resonances have been assigned on the basis of chemical shift theory, intensity of the signals, multiplicities generated in SFORD spectra and the comparison with model compounds.     

"Green"-enzymatic synthesis of pegylated phenolic macromer and polymer

Environmentally benign synthesis of novel pegylated polyphenolics, by combining the extraordinary selectivities of a lipase and an oxidase to develop polymeric electrolytes for applications in dye sensitised solar cells.     

6‐Hydroxy‐2,2‐di­methyl‐3,4‐di­hydro‐2H‐benzo[b]pyran

The title compound, 2,2‐di­methyl­chroman‐6‐ol, C₁₁H₁₄O₂, has been identified as a side product from the condensation of hydro­quinone with 2‐methyl­but‐3‐en‐2‐ol. The pyran ring has a half‐chair conformation. The hydroxyl groups are involved in intermolecular hydrogen bonding which generates infinite spiral chains around the fourfold screw axes; the O?O hydrogen‐bonded distances are 2.661 (1) Å.     

Spectrophotometric determination of ciprofloxacin by ion pair formation

Various aspects of application of derivative spectrophotometry to chemical analysis and investigations of equilibria and kinetics of reactions are scrutinised. In this work the viability of a spectrophotometric technique for the determination of ciprofloxacin has been deliberated. The method is based on the formation of ion-association complexes of ciprofloxacin with nickel(II) tetra thiocyanate, which are extracted into organic solvent (40% n-butanol in methylene chloride) having absorption maxima at 623 nm. The precision and accuracy of the method was checked by UV reference methods. The validation study indicated the parameters, which are in good agreement with the data obtained from standard methods. The proposed method was fruitfully applied to determine ciprofloxacin in their tablet formulations.     

Modified Calcium Alginate Beads with Sodium Dodecyl Sulfate and Clay as Adsorbent for Removal of Methylene Blue

In present study, we have investigated the effect of an anionic surfactant sodium dodecyl sulfate (SDS) and clay on calcium alginate beads was studied to remove methylene blue (MB) and to improve the adsorption capacity. The effects of various experimental parameters, such as shaking rate, initial dye concentration, temperature, and pH on the adsorption rate, have been studied. Equilibrium studies showed that the sorption of the dye was enhanced in presence of SDS. Scanning electron microscope (SEM) analysis showed that SDS entrapped beads have more pores and cavities which could be responsible for improved adsorption of MB. The kinetics of cationic dye adsorption nicely followed pseudo-second-order process. The evaluated thermodynamic parameters (ΔG ^o, ΔH ^o, ΔS ^o) suggest endothermic adsorption of MB. The results revealed that the surfactant entrapped alginate could be considered as potential adsorbents for MB removal from aqueous solutions.