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Bacterial and fungal infections are the major effects to cause the numerous disorders in health. To overcome such disorders there will be needed to carry out the studies to find potent antimicrobial agents from many years. The titled compounds containing coumarin-dithiocarbamate hybrids have emerged as potential candidate to be useful as anti-microbial agents. Compound (3i) shows significant strong anti-microbial activity against all tested bacterial and fungal strains. These compounds have been synthesized under conventional as well as microwave irradiation methods. The structures of the desired compounds (3a-3l) were confirmed by spectral data (IR, 1H NMR, 13C NMR and MS). In addition, the structures of compounds 3a and 3e have been elucidated by single crystal X-ray diffraction technique, hirshfeld surface analysis and DFT studies. Further, molecular docking study has also been performed against 1AI9 enzyme of antifungal activity showed good binding interactions and is in agreement with the in vitro results.

We report a series of C N bridged coumarin-thiazolidine-2,4-dione derivatives 3(a–q). These compounds have been synthesized under both conventional as well as microwave irradiation techniques. The synthesized compounds were characterized by spectral and elemental analyses. The computational study performed for targeted compounds and results obtained were mimicking the potent bio-molecules. All the newly synthesized compounds were screened for their in vitro anti-microbial and anti-inflammatory activities and have shown promising results. In vitro Anti-microbial activity of compounds (3a) and (3i) was found to be most active with bacterial and fungal strains. The compound (3i) shows best anti-inflammatory activity with IC50 of 43.26 µg/mL against protein denaturation.

The title molecule has been synthesized, characterized spectroscopically (FT-IR, LC-MS, and NMR 1H and 13C) and the 3D structure was confirmed by single crystal X-ray diffraction studies. The compound crystallizes in triclinic P-1 space group with cell parameters a = 9.8619 (2) A, b = 10.6288 (2) A, c = 10.6369 (2) A, α = 92.8280 (10)°, β = 103.19 (10)° γ = 115.00 (10)°, V = 970.28 (3) A3 and Z = 2. The chromene ring makes a dihedral angle of 86.47 (8)o and 4.27 (6)o, with the pyridine and phenyl rings respectively. Intramolecular hydrogen bond of the type C—H…O is observed. The crystal structure is stabilized with intermolecular interactions of the type C—H…π. The Hirshfeld surfaces computational analysis was carried out and the inter contact percentage contribution to the surfaces are listed. The fingerprint plots for each inter contacts are drawn and the electrostatic potential surfaces were drawn on Hirshfeld surfaces.

A series of new coumarin-maltol hybrids (2a–2k) were selectively prepared in high yields under microwave irradiation. All the newly synthesized compounds were characterized by elemental and spectroscopic analysis. The synthesized compounds were evaluated for their in-vitro anticancer activity against two human cancer cell lines viz., A-549 (human lung carcinoma) and HeLa (human cervical cancer). Among the tested, compounds (2a) and (2d) were found to be potent cytotoxic with IC50 values in the range of 2.47–4.26 µM on A-549 and HeLa cancer cells. DNA cleavage study by gel electrophoresis method revealed that the compounds (2a), (2j) and (2k) were found to cleave the DNA completely, as no traces of DNA were found. Furthermore, Molecular docking was performed against 4TZK enzyme of E. coli, which showed good binding interactions and is in agreement with the in vitro anti-microbial results.

A series of novel coumarin-piperazine derivatives (3a–3h) were synthesized and characterized by IR, 1H, 13C NMR and GC–MS. All the synthesized compounds were tested by in-vitro anti-inflammatory and anti-microbial activity. The compounds (3a), (3d), (3h) and (3f) were found to be potent anti-inflammatory activity with IC50 values in the range of 37.15–61.93 μg/mL. The compounds (3a), (3d) and (3f) showed potent anti-microbial activity with MIC values in the range of 0.5–2 μg/mL. Furthermore, Molecular docking study was performed against 1AD4 enzyme of S. aureus, which exhibited good binding interactions and also the compounds (3a), (3e), (3f) and (3h) have higher C score values than ciprofloxacin.

In the present study, an easy and efficient microwave-assisted protocol has been adopted for the synthesis of quinoline-based pyrazolines derivatives 3(a–i). The newly synthesized 3-(4‑hydroxy‑2-oxo-1,2-dihydroquinolin-3-yl)-5-phenyl-4,5-dihydropyrazole-1-carbothioamide derivatives were characterized by IR, 1H, 13C NMR, Mass and Elemental analyses. In-vitro anti-tubercular assay of compounds 3(a-i) has shown moderate to good activity against M. tuberculosis (H37Rv) strain with MIC's ranging between 0.05–6.25 µg/mL. In-silico study further supported the observed results with higher C-score values. Further, the compounds were also screened for in-vitro antibacterial and antifungal activity, wherein compound 3d and 3i exhibited excellent antibacterial activity and compound 3 g and 3 h were found to exhibit significant antifungal activity. The predicted ADME properties suggested a good pharmacokinetic profile for the newly synthesized compounds.

An efficient, high yields and rapid synthesis of N-tert-butyl-4-(4-substituted phenyl)-2-((substituted-2-oxo-2H-chromen-4-yl)methylthio)-6-oxo-1,6-dihydropyrimidine-5-carboxamide derivatives (4a–4j) under microwave-irradiation has been described. All the newly synthesized compounds (4a–4j) were characterized by elemental analysis and spectroscopic studies. The synthesised compounds (4a–4j) were evaluated for their antibacterial activity by agar-well diffusion method and anti-inflammatory activity by egg albumin denaturation method. The compound (4f) exhibits antibacterial effect with MIC–2.5 μg/mL against gram positive S. aureus bacterial strain compared to standard ciprofloxacin drug (MIC–10 μg/mL). The compound (4c) shows an inhibition of heat induced protein denaturation 75.42% at a concentration of 31.25 μg/ml and is almost ten times more active than compared to standard aceclofenac drug (5.50%). Molecular docking study has been performed for all the synthesized compounds with S. aureus dihydropteroate synthetase (DHPS) and results obtained are quite promising.

The presence of hydroxyl groups at the C4 and C7 positions in coumarin backbone has been proposed as a potential modification site for providing excellent bioactive molecules according to previous studies. The titled compounds have been synthesized under conventional as well as microwave irradiation methods. The microwave approach considered to be more admirable then conventional method due to its selectivity, shorter reaction time, reaction rate enhancement, and higher yield. Synthesized coumarin-carbonodithioate derivatives were characterized by IR, 1H NMR, 13C NMR and Mass spectroscopic study and screened for their anti-microbial activity. In vitro study reveals that the synthesized 5b and 5c coumarin derivatives show excellent anti-microbial activity against bacterial and fungal strains. Anti-microbial assays against standards coupled with in silico molecular docking studies indicated that 5b and 5c showed promising activity with higher C-score values.

A series of new coumarin linked with pyrimidine derivatives have been synthesized via microwave irradiation. Structures of the synthesized compounds were characterized by IR, 1H NMR, 13C NMR, GC-MS and CHN analysis techniques. All newly synthesized compounds screened for their in-vitro anti-microbial and anti-cancer activities (Hela and A549 Cell lines). Further DNA cleavage studied and reports revealed that most of the synthesized compounds inhibit the growth of the pathogenic organism by genome cleavage as no traces of DNA were found. The present investigation points out that the synthesized coumarin-pyrimidine analogs are promising in targeted drug delivery systems, can be used for cancer therapy. Docking results also supported the studies. A good pharmacokinetic profile is suggested by theoretical calculation of ADME properties. Insights into enzyme inhibitor interactions provided by docking stimulations and permitted us to rationalize the observed SARs.

Compounds of oxygen, nitrogen and sulfur containing heterocycles are recognized as important lead compounds in medicinal chemistry. An efficient and rapid synthesis of novel coumarin-thiazolidine-2,4‑dione derivatives (3a-3j) were synthesized by microwave as well as conventional methods. The newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR and Mass spectral studies. The newly synthesized molecules were screened for their anti-inflammatory activity. In vitro study reveals that, compound (3 g) shows significant strong anti-inflammatory broad spectrum activity. Anti-inflammatory activity of compound (3 g) has shown excellent activity with IC50 value of 46.62 µg/mL.

A number of new substituted (2H-chromen-2-one)-phenol derivatives (3a-3j) were synthesized by Williamson ether reaction fallows an SN2 bimolecular nucleophilic substitution mechanism. The titled compounds have been characterized by IR, 1H NMR, 13C NMR and Mass spectral studies. As predicted, the derivatization of benzyloxy phenol with coumarin via ether linkage enhanced the activity of the titled compounds against four bacterial and four fungal strains. Compound (3d) shows significant strong anti-microbial broad spectrum activity against all tested bacterial and fungal strains. Anti-bacterial assay against standard coupled with in silico molecular docking studies indicated that (3d) shows promising activity with higher C-score values.

An easy and efficient microwave-assisted protocol has been developed for the synthesis of coumarin-purine hybrids (3a-3j). The newly constructed 1,3-dimethyl-7-((substituted)-2-oxo-2H-chromen-4-yl)methyl)-1H-purine-2,6(3H,7H)-dione derivatives were evaluated for their in vitro antioxidant activity by DPPH free radical-scavenging ability assay and DNA cleavage by using calf thymus. The compound 3i, shows the most excellent DPPH scavenging activity with a –OH substitution at C7 of coumarin ring. In addition, the structure of compound 3f, has been elucidated using single crystal X-ray diffraction technique. Theoretical calculations (DFT) were carried out using Gaussian09 program package and B3LYP correlation function. Full geometry optimization were carried out using 6-311G++(d, p) basis set and the frontier orbital energy were presented. Hirshfeld surface analysis was used for the intermolecular interactions in the crystal structure. The experimental result of the compound 3f has been compared with the theoretical results and it was found that the experimental data are in a good agreement with the calculated values.

A series of 2-(2-(4-fluorobenzyl)-6-(substituted phenyl) pyrimidin-4-yl)-3H-benzo[f]chromen-3-one derivatives (1a–1o) were selectively prepared in high yields under microwave irradiation. The synthesized compounds were characterized by elemental and spectroscopic analysis; in addition the structures of compound (1a), (1b) and (1j) were elucidated by the X-ray diffraction technique. Compounds (1a–1o) were evaluated for their in-vitro antitubercular activity while the most active compounds were further subjected for their cytotoxicity and DNA cleavage study. Results revealed that most of the tested compounds displayed potent antitubercular activity with MIC in the range 0.05–2.81 μg/mL. Among them, compound (1b) possessed excellent activity (MIC 0.05 μg/mL) against M.tb H37Rv strain and exhibited low level of cytotoxicity against Vero cells, which suggested compound (1b) is a promising lead for subsequent investigation in search of new antitubercular agents. DNA cleavage by gel electrophoresis method revealed that compounds (1b, 1g, 1k and 1n) were found to cleave the DNA completely.

Spectra of each derivatives

Spectrum of each derivatives

An efficient and rapid synthesis of coumarin–thiazoline hybrids (1a–1j) under microwave irradiation is described with high yields. The synthesized compounds were characterized using elemental and spectroscopic analysis; in addition, the structures of compounds 1a, 1b, 1e and 1h have been elucidated using single crystal X-ray diffraction techniques. All the newly synthesized compounds were screened for their in vitro anti-tubercular activity and in a DNA cleavage study, while the most active compounds were subjected to a cytotoxicity assay on Vero cell lines. Among those tested, compound 1b exhibited excellent anti-tubercular activity (MIC 0.09 μg ml−1) with a low level of cytotoxicity, suggesting that compound 1b is a promising lead for subsequent investigations in search of new anti-tubercular agents. Furthermore, a DNA cleavage study using an agarose gel electrophoresis method revealed that compounds 1b, 1d, 1f and 1i cleaved DNA more efficiently and thereby exhibit nuclease activity.

An efficient and rapid synthesis of 3-(2-(4-fluorobenzyl)-6-(substituted phenyl) pyrimidin-4-yl)-2H-chromen-2-one derivatives (1a–1l) under microwave-irradiation has been described in high yields. All the newly synthesized compounds (1a–1l) were characterized by elemental and spectroscopic analysis. In addition, the structure of compound (1a) and (1b) has been elucidated by the single crystal X-ray diffraction technique. The synthesized compounds (1a–1l) were evaluated for their anticancer activity against two human cancer cell lines viz., A-549 (human lung carcinoma) and MDA-MB-231 (human adenocarcinoma mammary gland). The results revealed that several synthesized compounds exhibit significant cytotoxicity against the two tested cancer cell lines with IC50 < 10 μM. Among these, compound (1j) exhibited potent activity against the A-549 cell line, which is comparable with standard drug Cisplatin, whereas compound (1b) was found extremely active against the MDA-MB-231 cell line and proved to be more potent than standard drug Cisplatin. DNA cleavage study by the gel electrophoresis method revealed that compounds (1b), (1e), (1g) and (1j) inhibit the growth of the pathogenic organism by cleaving the genome as no traces of DNA were found.

Removal of fluorine from water was investigated by electrodialysis (ED) method. In order to check the efficacy of ED unit, parameters like applied potential, the pH; initial fluoride concentrations and flow rates were varied. Significant results were obtained with concentrations of less than 10 ppm. Results were satisfactory in meeting the maximum contaminate level (MCL) of 0.01 ppm for fluoride. Effect of working parameters on energy consumption was investigated using ion-exchange membranes. Results of this study are useful for designing and operating different capacities of ED plants for recovering different ions. The ED plant was found to be satisfactory to produce a good quality drinking water from the simulated mixture by removing the unwanted ions.

In this work, an attempt has been made to characterize, isolate and elucidate the structure of unusual fatty acid in the seed oil of Aegle marmelos Corre. Further, this nonedible seed oil is screened for its bio-diesel or industrial feedstock property. The Aegle marmelos Corre seeds yielded 49.0% oil. The seed oil contains 12.5% of 12-hydroxyoctadec-cis-9-enoic acid (ricinoleic acid) along with other normal fatty acids. The identification and characterization was supported by FTIR, 1H NMR, 13C NMR, MS, GC analysis and chemical degradation technique. A good agreement is seen between the calculated and experimental results of iodine value (IV) and saponification value (SV). The prominent parameters of bio-diesel such as cetane number (CN), lower heating value (LHV) and higher heating value (HHV) are deployed to envisage the quality of oil for use as bio-diesel. This seed oil is nonedible and is found to be the alternative feed stock for the production of bio-diesel since it convenes the major specifications of bio-diesel. The bio-diesel property of fatty acid methyl esters (FAMEs) of this seed oil is compared with other bio-diesels.

A series of novel 2-(1H-benzimidazol-2-ylsulfanyl)-N-(4-oxo-2-phenyl-thiazolidin-3yl)-acetamide 5a-j have been synthesized from various aldehydes and 2-(5-phenyl-[1,3,4]-oxadiazol-2-ylmethylsulfanyl)-1H-benzimidazole 6a-j from various benzoic acids. These compounds were screened for their in-vitro anti-bacterial activity against Staphylococcus aureus and Enterococcus faecalis as Gram positive, Klebsiella pneumoniae and Escherichia coli as Gram negative bacterial strains and for in-vitro anti-fungal activity against Asperigillus fumigatus and Candida albicans. The in vitro cytotoxic properties were studied using brine shrimp bioassay. Results revealed that, compounds 5b, 5d, 5g, 5i, 6b, 6e, 6f, and 6i showed excellent activity against a panel of microorganisms. The cytotoxic activities of 5b, 5g, 5i, 6b, 6f, 6h, and 6i were found to be good. All the newly synthesized compounds were characterized by elemental analysis, IR, (1)H-NMR, (13)C-NMR and MS.

For the first time Phosphotungstic acid (PTA), is used as a some new catalyst for the synthesis of tetrahydroquinoline derivatives with high yields is described. PTA a heterogeneous catalyst is inexpensive, easily available, eco-friendly, water soluble, recoverable, stable to aqueous reaction conditions and further more, these 2-methyl tetrahydroquinoline derivatives shows a remarkable fluorescence property.

New organic reactions allow chemical transformations which were previously unknown. Therefore, new reactions are important contributions to progress in the field of organic synthesis. Herein, we are reporting a simple, one-pot, efficient three-component synthesis of novel 3-chloro-4-[4-(2-oxo-2H-chromen-4-ylmethoxy)phenyl]-1-phenylazetidin-2-one derivatives using 4-(2-oxo-2H-chromen-4-ylmethoxy)benzaldehydes, anilines, and chloroacetyl chloride in the presence of triethyl amine as a catalyst under different conditions. Taking into account environmental and economic considerations, the protocol presented here has the merits of simple operation, convenient work-up, being environmentally benign, and providing good yields. The synthesized compounds were characterized by IR, 1H NMR, 13C NMR, MS, and elemental analysis.

For the first time, copper dipyridine dichloride (CuPy2Cl2) is used as an efficient and reusable catalyst for the imino Diels–Alder reaction of para-substituted anilines with N-vinylpyrrolidinone, N-vinylcarbazole, and N-vinylcaprolactam in acetonitrile to afford the corresponding 2-methyl-4-substituted-1,2,3,4-tetrahydroquinoline derivatives in excellent yields with good purity. The products were characterized by FTIR,1H NMR,13C NMR, MS, and elemental analysis.

An eco-friendly catalytic amount (0.3 g) of tungstate-promoted zirconia (WO x /ZrO2) solid acid catalyst has been explored in the synthesis of 2-aryl benzimidazoles using aryl aldehydes and o-phenylenediamine. This is one of the fundamental aspects in green chemistry for simple experimental and product isolation protocol combined with easy recovery and reusability of the catalyst. It is expected to contribute in the development of clean and environment friendly strategy for synthetic protocols. The incorporated promoter showed strong influence on the surface and bulk properties of zirconia. The catalytic activity results suggest that the methodology adopted offers significant improvements for the synthesis of benzimidazole derivatives with respect to yields, simplicity and green aspects by avoiding toxic conventional catalysts and solvents. Henceforth, a good substrate conversion and excellent product selectivity were obtained over tungstate promoted zirconia solid acid catalyst. A straightforward and general method has been developed for the synthesis of 2-aryl benzimidazoles using aryl aldehydes and o-phenylene diamine in the presence of eco-friendly tungstate-promoted zirconia (WO x /ZrO2) solid acid catalyst.

Arsenic removal from drinking water is a major problem in many parts of the world. Acute and chronic arsenic exposure through drinking water has been reported in many countries, especially Argentina, Bangladesh, India, Mexico, Mongolia, Thailand and Taiwan, where a large proportion of ground water is contaminated with arsenic at levels from 100 to over 2000 μm/L. In this work, we have investigated the arsenic removal by the membrane-based nanofiltration (NF) technique. The results of this study demonstrate that arsenate ions removal by NF with a high rejection of 99.80% along with total dissolved solids (TDS) and other contaminates were achieved. Significant flux was retained at the end of each NF experiment with operation time of 180 min, which suggests that membranes were not affected by the fouling phenomenon during the process run. The feasibility of membranes for treating drinking water by varying feed pressure, pH and feed concentration was tested on the separation performance of the thin film composite NF membranes.

Novel biodegradable aliphatic poly(ether-urethane)s (PEUs) based on pluronic F-68 (PLF68) and castor oil were synthesized by the solution polymerization technique. These polymers were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic spectroscopy (1HNMR) and gel permeation chromatography (GPC) to confirm the PEU formation and the molecular weight. Moderate molecular weight PEUs were obtained and converted into microspheres by solvent evaporation method to study the controlled release (CR) characteristics for 5-flurouracil (5-FU). PLF-68 acts as amphiphilic filler, which enhances the release of a hydrophobic drug such as 5-FU. Sizes of the microspheres as measured by laser light scattering technique ranged between 15 and 42 µm. An increase in the size of particles was observed with increasing molar ratio of PLF-68 with respect to castor oil. The percentage encapsulation efficiency varied between 71 and 98. Surface morphology of the microspheres as studied by scanning electron microscopy (SEM) revealed the spherical nature of the particles with wrinkles on their surfaces. The release of 5-FU through the microspheres was investigated in pH 7·4-phosphate buffer. An increase in release rate was observed with increasing molar ratio of PLF68 with respect to castor oil.

A new Schiff's base and 2-azetidinone derivatives obtained via the corresponding 3-benzo [4,5] imidazo [2,1-b] thiazol-3-yl-chromen-2-one by Vilsmeier–Haack formylation scaffold is described. Our design is aimed at obtaining new triheterocyclic and tetraheterocyclic derivatives.

Nanofiltration (NF) and reverse osmosis (RO) thin film composite polyamide membrane modules were used to remove the color from the contaminated solution mixture. The feasibility of membrane processes for treating simulated mixture by varying the feed pressures (100–400 psi) and feed concentrations was studied to assess the separation performance of both NF and RO membranes. It was found that the efficiency of NF and RO membranes used in the treatment of colored water effluents was greatly affected by the presence of salts and dyes in the mixture. Color removal by NF with a high rejection of 99.80% and total dissolved solids (TDS) of 99.99% was achieved from RO by retaining significant flux rate compared to pure water flux, which suggested that membranes were not affected by fouling during the simulated wastewater process operation. The effect of varying concentrations of Na 2 SO 4 salt and methyl orange (MO) dye on the performance of spiral wound membranes was determined. Increasing the dye concentration from 500 to 1000 mg/L resulted in a decrease of salt rejection at all operating pressures and for both concentrations of 5000 and 10,000 mg/L as the feed TDS. Increasing the salt concentration from 5000 to 10,000 mg/L resulted in a slight decrease in dye removal.

A new series of novel 5-(nitro/bromo)-styryl-2-benzimidazoles (1-12) has been synthesized by simple, mild and efficient synthetic protocol by attempted condensation of 5-(nitro/bromo)-o-phenylenediamine with trans-cinnamic acids in ethylene glycol. Screening for in vitro anti-tubercular activity against Mycobacterium tuberculosis H(37) Rv, anti-bacterial activity against Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae bacterial strains and anti-fungal activity against Candida albicans and Asperigillus fumigatus fungal strains were carried out. Compounds 5, 7, 8, 9, 11 showed higher anti-tubercular activity and compounds 7, 8, 10, 11, 12 have proved to be effective with MIC (microg/ml) and emerged as lead molecules showing excellent activities against a panel of microorganisms. All synthesized compounds were characterized using IR, (1)H, (13)C NMR, GC-MS and elemental analysis.

The efficient and rapid synthesis of 5-nitro-2-aryl substituted-1H-benzimidazole libraries (1a-1j) has been established. Thus, both microwave and conventional cyclo-condensation of 4-nitro ortho-phenylenediamine with various phenoxyacetic acids were carried out in the presence of HCl catalyst. The microwave synthesis route afforded advantages, such as good to excellent yields, shorter reaction time (2.5-3.5 min), readily available starting material, and simple purification procedure, which distinguish the present protocol from other existing methods used for the synthesis of benzimidazole libraries. Bioassay indicated that all the compounds showed in vitro antimicrobial activity against Vancomycin resistant enteroccoccus, Staphylococcus aureus, Micrococcus, Bacillus subtilis (gram-positive bacteria) and Shigella dysentery, Escherichia coli (gram-negative bacteria) and Candida albicans, Aspergillus niger, Penicillium (fungi). The minimum inhibitory concentration (MIC) was determined for test compounds as well as for reference standards.

In this research work, we report an efficient and easy method for preparation of 2-arylbenzimidazoles from o-phenylenediamines and phenoxyacetic acids under microwave condition using a Wells–Dawson heteropolyacid (H6P2W18O62 · 24H2O) as catalyst. The heterogeneous reaction conditions provided a very simple, environmentally friendly, clean, economical and selective protocol, for the preparation of benzimidazole derivatives. The catalyst is easily recycled and reused without loss of the catalytic activity. In this research work, we report an efficient and easy method for preparation of 2- arylbenzimidazoles from o-phenylenediamines and phenoxyacetic acids under microwave condition using a Wells-Dawson heteropolyacid (H6P2W18O62 · 24H2O) as catalyst. The heterogeneous reaction conditions provided a very simple, environmentally friendly, clean, economical and selective protocol, for the preparation of benzimidazole derivatives.

Phosphotungstic acid (PTA) is used an efficient catalyst for the von Pechmann condensation reaction of phenols and β-keto esters under solvent-free conditions. This method was compared with those of the reactions in the different solvents and catalysts. The methodology presented offers significant improvements for the synthesis of coumarins with regard to yield of products, simplicity in operation and green aspects by avoiding toxic conventional catalysts and solvents. Phosphotungstic acid (PTA) is used an efficient catalyst for the von Pechmann condensation reaction of phenols and β-keto esters under solvent-free conditions. This method was compared with those of the reactions in the different solvents and catalysts. The methodology presented offers significant improvements for the synthesis of coumarins with regard to yield of products, simplicity in operation and green aspects by avoiding toxic conventional catalysts and solvents.

Michelia champaca and Garcinia indica seeds yielded 45.0% and 45.5% of oil. The fatty acid profiles of both the seed oils were examined. The saponification value (SV), iodine value (IV) and cetane number (CN) of fatty acid methyl esters of both the seed oils were empirically determined. The saponification value (SV) and iodine value (IV) are in good agreement with the experimentally observed values. The fatty acid compositions, iodine value and cetane number were used to predict the quality of fatty acid methyl esters of oil for use as biodiesel. Thus, the fatty acid methyl esters of seed oils of M. champaca and G. indica were found to be the most suitable biodiesel and they meet the major specification of biodiesel standards. The selected plants M. champaca and G. indica have great potential for biodiesel. M. champaca and G. indica seed oils were found to contain keto fatty acids along with the other normal fatty acids, respectively. These fatty acids have been detected and characterized by UV, FTIR, 1H NMR, 13C NMR, MS, GC techniques and chemical transformations.

The objective of this research was to conduct constructive organic chemistry by using ethylene glycol as an efficient solvent and to achieve yields that were comparable to or better than those in other media. The reaction parameters, such as temperature (150–200 °C), density, and reaction time (6 h), have been systematically studied to understand whether ethylene glycol is as an efficient solvent and can have a positive effect on the chemistry with good yields. By tuning the parameters, the yields have been optimized to around 70%-80%. Thus, a new class of 2-alkyl substituted oleo-benzimidazole derivatives have been synthesized and characterized by FTIR, 1H NMR, 13C NMR, MS, and elemental analysis.Key words: oleochemistry, ethylene glycol, oleo-benzimidazole derivatives, unusual fatty acids.

4-Nitrophthalic acid was found to be an effective catalyst for the imino Diels-Alder reaction of N-benzylideneanilines with 3,4-dihydro-2H-pyran and 2,3-dihydrofuran to afford pyrano- and furanoquinolines in good yields. It was also found that aryl amines react smoothly with 3,4-dihydro-2H-pyran and 2,3-dihydrofuran under the same condition to afford the corresponding pyrano- and furanoquinolines in high yields. This catalyst is inexpensive, easily available, water soluble, and stable to aqueous reaction conditions.

pH-sensitive novel semi-interpenetrating networks (semi-IPN) of N , N ′-dimethylacrylamide (NNDMA) and chitosan (CS) were prepared in the form of microspheres by water-in-oil (w/o) emulsion technique. Microspheres were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffractometry (X-RD) technique to confirm the crosslinking as well as polymorphism of chlorothiazide (CLT) drug. X-RD and DSC techniques indicated molecular level dispersion of CLT in the IPN matrix. Scanning electron micrographs (SEM) of the microspheres indicated smooth surfaces of the spherical microspheres. Cumulative release characteristics of the matrices for CLT, anti-hypertensive drug, were investigated in pH 1.2 and 7.4 media. Particle size and size distribution of the microspheres was measured by dynamic laser light diffraction technique. It was possible to release CLT in a controlled manner up to 12 h.

A novel semi-interpenetrating (semi-IPN) graft copolymer of 2-hydroxyethyl methacrylate (HEMA) with chitosan (CS) has been prepared in the form of microspheres, using water-in-oil (W/O) emulsion technique. Microspheres were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray diffractometry (X-RD) to confirm the crosslinking and polymorphism of indomethacin (IDM). The X-RD and DSC techniques indicated a molecular-level dispersion of IDM in the IPN matrix. Scanning electron micrographs (SEM) taken at the cross section of the microspheres have shown rough surfaces around the microspheres. The sustained release characteristics of the matrices for IDM, an anti-inflammatory drug, were investigated in pH 7.4 media. Particle size and size distribution of the microspheres were studied by laser light diffraction particle size analyzer. The drug was released in a sustained manner for up to 12 h. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 2006

Exploration of a new working system to investigate the removal of chromium ions in its hexavalent oxidation state singly in connection with different parameters and associated moieties in feed mixtures was performed using an indigenously built electrodialysis (ED) pilot plant comprising a set of ion-exchange membranes. In order to check the efficacy of ED unit, parameters like applied potential, pH, initial chromium concentration of diluate and flow rates were varied. Significant results were obtained with lower initial concentrations of less than 10 ppm. Results were satisfactory in meeting the maximum contaminate level (MCL) of 0.1 ppm for chromium. Cowan and Brown’s method was adopted to determine the limiting current density in the ED experiment. Effect of working parameters on energy consumption was investigated using ion-exchange membranes. Results of this study are useful for designing and operating different capacities of ED plants for recovering different ions. The ED plant used in this research was found to be satisfactory to produce good quality drinking water from the simulated mixture by removing the unwanted ions.

Carbohydrate polymeric blend microspheres, consisting of sodium alginate (NaAlg) and methylcellulose (MC) were prepared by water-in-oil (W/O) emulsion method. These microspheres were cross-linked with glutaraldehyde and loaded with nifedipine (NFD), an anti-inflammatory drug. The microspheres were characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and laser particle size analyzer. DSC thermograms of NFD-loaded NaAlg–MC microspheres confirmed the molecular level distribution of NFD in the polymer matrix. SEM picture of the microspheres suggested the formation of spherical particles. Swelling experiments on the microspheres provided important information on drug diffusion properties. Release data have been analyzed using an empirical equation to understand the nature of transport of drug containing solution through the polymeric matrices. The controlled release characteristics of the matrices for NFD were investigated in pH 7.4 media. Particle size and size distribution of the microspheres was studied by laser light diffraction particle size analyzer. Drug was released in a controlled manner up to 12 h.

Novel poly(acrylamide-methylmethacrylate) copolymeric core-shell microspheres crosslinked with N,N'-methylene bisacrylamide have been prepared by free radical emulsion polymerization using varying amounts of acrylamide (AAm), methylmethacrylate (MMA) and N,N'-methylene bisacrylamide (NNMBA). 5-Fluorouracil was loaded into these microspheres during in situ polymerization (method-I) as well as by the absorption and adsorption technique (method-II). The core-shell microspheres have been characterized by differential scanning calorimetry (DSC) and X-ray diffractometry (X-RD) to understand about the drug dispersion in microspheres. Scanning electron microscopy (SEM) was used to assess the surface morphology of particles prepared. In vitro release of 5-fluorouracil has been studied in terms of core-shell composition, amount of crosslinking agent and amount of 5-fluorouracil in the microspheres. Core-shell microspheres with different copolymer compositions have been prepared in yields ranging 80-85%. DSC and X-RD techniques indicated a uniform distribution of 5-fluorouracil particles in core-shell microspheres, whereas SEM suggested the formation of well-defined core-shell structures. The in vitro drug release indicated that particle size and release kinetics depend upon copolymer composition, amount of crosslinking agent used and amount of 5-fluorouracil present in the microspheres. Prolonged and controlled release of 5-fluorouracil was achieved when drug was loaded by method-I instead of method-II.

A hybrid nanofiltration (NF) and reverse osmosis (RO) pilot plant was used to remove the color and contaminants of the distillery spent wash. The feasibility of the membranes for treating wastewater from the distillery industry by varying the feed pressure (0-70 bar) and feed concentration was tested on the separation performance of thin-film composite NF and RO membranes. Color removal by NF and a high rejection of 99.80% total dissolved solids (TDS), 99.90% of chemical oxygen demand (COD) and 99.99% of potassium was achieved from the RO runs, by retaining a significant flux as compared to pure water flux, which shows that membranes were not affected by fouling during wastewater run. The pollutant level in permeates were below the maximum contaminant level as per the guidelines of the World Health Organization and the Central Pollution Control Board specifications for effluent discharge (less than 1,000 ppm of TDS and 500 ppm of COD).

Mappia foetida is a medium-sized tree, which belongs to Olacaceae plant family. It is found to contain 16.0% of 3-keto-octadec- cis -15-enoic acid previously hitherto unknown in the Olacaceae plant family. It also contains other normal fatty acids such as palmitic acid (12.3%), stearic acid (4.2%), oleic acid (16.2%), linoleic acid (11.6%) and linolenic acid (39.7%). The identification and characterization was based on UV, FTIR, 1 H NMR, 13 C NMR, MS, GLC analysis and Chemical degradations.