Environmental Friendly Synthetic Modification of Amberlite XAD-2 Resin for the Removal of Highly Toxic Hexavalent Chromium from Water.

Amberlite XAD-2 functionalized by coupling through -C=N- spacer with isatin via an environmental friendly protocol. The modified resin was used for the evaluation of its sorption capacity towards toxic Cr (VI) ions using spectrophotometer. pH, volume, sorbent amount, initial concentration of Cr(VI) ions, and agitation time were optimized. The Freundlich and Dubinin- Radushkevich models gave better fit to isotherm data than Langmuir model. The evaluation of kinetic data indicated pseudo-first-order kinetics followed by sorption process. Thermodynamic parameters were also evaluated. Maximum recovery was obtained at 10 mL of 0.1M NaOH. Spiking methodology was used to confirm the validity of proposed method. The results revealed that developed method can be used for the removal of Cr(VI) ions efficiently from water, as well as reused for three cycles.

Insulinotropic action of 2, 4-dinitroanilino-benzoic acid through the attenuation of pancreatic beta-cell lesions in diabetic rats.

Beta cell destruction plays a key role in the pathogenesis of type 1 diabetes mellitus. It has also been argued that beta-cell mass is compromised in some cases of type 2 diabetes, although this is still debated. Currently, the failure of oral antidiabetic insulin secretagogue drugs to properly manage type 2 diabetes demands novel approaches for the treatment of this condition. The aim of the present study was to investigate the in vitro and in vivo antidiabetic effect in STZ-induced diabetic rats, and maximum tolerated dose (MTD) safety of novel anthranilic acid derivative, 2, 4-dinitroanilino-benzoic acid (1). Anthranilic acid derivative 1 was also evaluated for insulinotropic action on STZ-mediated pancreatic beta-cell lesions in diabetic rats. During an eight week study, oral glucose tolerance test, fasting blood glucose, and serum insulin levels, and pancreatic insulin contents were measured in four different groups of Wistar rats; control, STZ-induced diabetic, gliclazide-treated, and anthranilic acid derivative-treated diabetic rats. Beta-cell number and islet area were also quantified, and immunohistochemical study was performed. In vitro studies in cells showed that 2, 4-dinitroanilino-benzoic acid (1) did not adversely effect the cells viability. We found that the derivative 1 significantly improved the glucose tolerance, fasting blood glucose, and HbA1c levels, serum insulin levels, and pancreatic insulin contents (P < 0.05), comparable to gliclazide-treated group. The derivative 1 exhibited a significant insulinotropic action on diabetic pancreas, and caused an increased immunoreactivity for insulin, as compared to gliclazide-treated group. Together these results suggest that treatment of diabetic rats with 2, 4-dinitroanilino-benzoic acid (1) improved the glucose tolerance, fasting blood glucose, and HbA1c levels most probably by restoring the functional activities of the pancreas via its insulinotropic action. This indicates that the derivative 1 can serve as lead for the treatment of diabetes caused by low insulin levels.

Development of microwave assisted spectrophotometric method for the determination of glucose.

A spectrophotometric method was developed based on the microwave assisted synthesis of Maillard product. Various conditions of the reaction were optimized by varying the relative concentration of the reagents, operating temperature and volume of solutions used in the reaction in the microwave synthesizer. The absorbance of the microwave synthesized Maillard product was measured in the range of 360-740 nm using UV-Visible spectrophotometer. Based on the maximum absorbance, 370 nm was selected as the optimum wave length for further studies. The LOD and LOQ of glucose was found 3.08 µg mL(-1) and 9.33 µg mL(-1) with standard deviation of ±0.05. The developed method was also applicable to urine sample.

Synthesis of biologically active O-substituted derivatives of 1-[(3, 5-dichloro-2-hydroxyphenyl)sulfonyl]piperidine.

In the present work, a series of 2-O-substituted derivatives of 1-[(3,5-dichloro-2-hydroxy phenyl) sulfonyl]piperidine (5a-j) were synthesized. These derivatives were geared up by the coupling of 3,5-dichloro-2-hydroxy benzenesulfonyl chloride (1) with piperidine (2) under dynamic pH control in aqueous media to form parent compound 1-[(3,5-dichloro-2-hydroxyphenyl)sulfonyl]piperidine (3), followed by the substitution at oxygen atom with different electrophiles (4a-j) in the presence of sodium hydride (NaH) and dimethyl formamide (DMF) to give a series of O-substituted derivatives of sulfonamides bearing piperidine nucleus 5a-j. The synthesized O-substituted sulfonamides were spectrally characterized. The bioactivity of all the synthesized compounds were evaluated against lipoxygenase (LOX), acetylcholinesterae (AChE) and butyrylcholinesterase (BChE) enzymes and found to be having talented activity against butyrylcholinesterase enzyme.

A facile synthesis of novel biologically active 4-hydroxy-N'-(benzylidene)-2H-benzo[e][1,2]thiazine-3-carbohydrazide 1,1-dioxides.

A novel series of potentially biologically active 4-hydroxy-N'-(benzylidene)-2H-benzo[e][1,2]thiazine-3-carbohydrazide 1,1-dioxides were synthesized starting from ultrasonic mediated N-alkylation of sodium saccharin with methyl chloroacetate. Ring expansion of methyl(1,1-dioxido-3-oxo-1,2-benzisothiazol-2(3H)-yl)acetate followed by its hydrazinolysis afforded 4-hydroxy-2H-1,2-benzothiazine-3-carbohydrazide 1,1-dioxide which was reacted in a straight forward manner with various benzaldehydes in an ultrasonic bath to get the title compounds. All of the synthesized compounds were subjected to preliminary evaluation for their antibacterial and DPPH radical scavenging activities.

Synthesis and in vitro leishmanicidal activity of some hydrazides and their analogues.

Twenty-one hydrazides were synthesized by treating different esters with hydrazine hydrate. Substituted hydrazides were obtained by treating hydrazides with alkyl/aryl/acyl halides. Some of these compounds exhibit potential in vitro leishmanicidal activity. The structures of all the synthesized compounds were confirmed by spectroscopic analysis.

Determination of nicotinamide and 4-aminobenzoic acid in pharmaceutical preparation by LC.

A rapid, precise and time saving high performance liquid chromatographic method has been developed and validated for the simultaneous determination of nicotinamide and 4-aminobenzoic acid in pharmaceutical preparation. The method involves isocratic elution of mobile phase through column in a reverse phase chromatography with UV detection at 254 nm. The ranges of quantification for nicotinamide and 4-aminobenzoic acid were 11-34 microg ml(-1) and 37-113 microg ml(-1), respectively. Investigating specificity, linearity, precision, accuracy, robustness and ruggedness performed the validation of the method.