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Chalcones3a-fwere prepared by reacting thiophene containing pyrazolyl aldehyde (2) with different 2-hydroxy acetophenones 1a-f. The compounds3a-f were transformed into different Pyrazolines 4a-f. The formation of chromene derivatives 5a-f occurred from the cyclization of 3a-f, which were then transformed into pyrazole derivatives 6a-f. Newly synthesized compounds have promising antibacterial activity against S.typhii and S.aureus, while weak activity against B.subtilis and E.coli. Compounds 5d and 6d had significant antifungal action towardsA. niger, while most of the compounds were moderately active towards T.viride. Some of the synthesized compounds showed promising α-amylase inhibitory activity at 1 mg/mL concentration.

In the present protocol, biogenic synthesis of ZnO nanoparticles using an aqueous extract of weed, i.e. Parthenium is efficiently carried out. The proficient and operationally simple catalytic application of biogenic ZnO nanoparticle is explored towards a synthesis of pharmaceutically relevant and densely functionalized polyhydroquinolines by condensation of four components viz. aromatic aldehyde, dimedone, ethyl acetoacetate, and ammonium acetate. The synthesized polyhydroquinolines were screened for their antimicrobial activity against bacteria and fungi; some of them exhibit better to excellent activity. The developed protocol is enriched with captivating advantages such as excellent yields, shorter reaction time, recyclable catalyst and constructive use of an aqueous extract of Parthenium for the synthesis of ZnO nanoparticle.

The biogenic synthesis of copper oxide nanoparticles (CuO NPs) from the leaf extract of Alpinia zerumbet was investigated in this protocol. The basic nature of A. zerumbet leaf extract helps in CuO NPs synthesis. The catalytic activity of A. zerumbet-fabricated CuO NPs is explored in water at room temperature only in the presence of NaPTS hydrotrope. The green catalytic protocol is investigated via synthesis of 1,8-dioxooctahydroxanthene. The biogenic leaf extract fabricated CuO NPs are efficiently reactive, stable and recyclable in aqueous solution of sodium p-toluenesulfonate (NaPTS) hydrotrope. CuO/NaPTS proved to be the best catalytic system as synergistic nanotrope in terms of yield and time of reaction in water at room temperature. The green synthetic approach of CuO NPs, greener medium, easy workup and proficient recyclability are advantages in the said protocol. This is first time report of catalytic activity of biogenic CuO NPs in water at room temperature in the presence of NaPTS.

A series of novel derivatives of 1-(2-{2-[2-(4-fluorophenyl)-4-methylthiazol-5-yl]-1H-benzo[d]imidazol-1-yl}acetyl)-4-phenylthiosemicarbazide, 5-({2-[2-(4-fluorophenyl)-4-methylthiazol-5-yl]-1H-benzo[d]imidazol-1-yl}methyl)-4-phenyl-4H-1,2,4-triazole-3-thiol and 5-({2-[2-(4-fluorophenyl)-4-methylthiazol-5-yl]-1H-benzo[d]imidazol-1-yl}methyl)-N-phenyl-1,3,4-thiadiazol-2-amine have been synthesized by the conventional method as well as using MW irradiation. All newly synthesized compounds have been tested for antibacterial activity. Several products have demonstrated moderate activity against gram positive and gram negative bacterial strains.

Herein, we report nitrogen-doped TiO2 (N-TiO2) solid-acid nanocatalysts with heterogeneous structure employed for the solvent-free synthesis of α-aminophosphonates through Kabachnik–Fields reaction. N-TiO2 were synthesized by direct amination using triethylamine as a source of nitrogen at low temperature and optimized by varying the volume ratios of TiCl4, methanol, water, and triethylamine, under identical conditions. An X-ray diffraction (XRD) study showed the formation of a rutile phase and the crystalline size is 10 nm. The nanostructural features of N-TiO2 were examined by HR-TEM analysis, which showed they had rod-like morphology with a diameter of ∼7 to 10 nm. Diffuse reflectance spectra show the extended absorbance in the visible region with a narrowing in the band gap of 2.85 eV, and the high resolution XPS spectrum of the N 1s region confirmed successful doping of N in the TiO2 lattice. More significantly, we found that as-synthesized N-TiO2 showed significantly higher catalytic activity than commercially available TiO2 for the synthesis of a novel series of α-amino phosphonates via Kabachnik–Fields reaction under microwave irradiation conditions. The improved catalytic activity is due to the presence of strong and Bronsted acid sites on a porous nanorod surface. This work signifies N-TiO2 is an efficient stable catalyst for the synthesis of α-aminophosphonate derivatives.

A new series of 2-(4,5,6,7-tetrahydrobenzo[c]isoxazol-3-yl)-4H-chromen-4-ones 5a-e were synthesized from 1-(2-hydroxyphenyl)-3-(4,5,6,7-tetrahydrobenzo[c]isoxazol-3-yl)propane-1,3-diones 4a-e in presence of acetic acid and conc. HCl. Compounds 4a-e were synthesized by Baker-Venkataraman rearrangement from 2-acetylphenyl 4,5,6,7-tetrahydrobenzo[c]isoxazole-3-carboxylate 3a-e in presence of pyridine and KOH and compounds 3a-e were synthesized from 4,5,6,7-tetrahydrobenzo[c]isoxazole-3-carboxylic acid 1 and substituted 2-hydroxy acetophenone 2a-e. All the synthesized compounds were characterized with the help of IR, 1H NMR, 13C NMR and mass spectroscopic techniques. All the compounds were screened for their in vitro anti-inflammatory activities. Furthermore, molecular docking study against COX-2 enzyme could provide valuable insight into the binding affinity of these molecules and the type of thermodynamic interactions governing their binding.

We have explored nanocrystalline ZnO and Cu-ZnO catalyst for the preparation of 3-styrylchromones with trans selectivity derived from 3-formylchromones. Synthesis of ZnO and Cu-ZnO nano flakes (NFs) was carried by precipitation technique. The analytical techniques such as UV-Visible spectroscopy, X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), field emission scanning electron microscopy (FESEM) and energy-dispersive analysis X-ray spectroscopy (EDAX) were used to characterize the catalysts. The XRD pattern showed highly pure wurtzite ZnO and Cu-ZnO. The FESEM images showed nano flakes such as sunflower seed morphology in the range width of 9–34 nm and length 90–180 nm. Doping of copper in ZnO was employed to study the selectivity of Knoevenagel and Knoevenagel-Doebner reactions. Knoevenagel condensation was catalyzed efficiently by pure ZnO nano flakes, whereas the Cu-ZnO nano flakes facilitate the Knoevenagel-Doebner reaction. Present synthetic protocols are novel, very clean and high yielding for synthesis of 3-styrylchromones. Almost same yield was observed to the recycled catalyst up to four runs. Keywords: Heterogeneous catalysis, ZnO nano flakes, Knoevenagel condensation, Knoevenagel-Doebner reaction, 3-Styrylchromone

An efficient, straightforward and rapid method has been developed for the synthesis of tetrahydrobenzo[α] xanthen-11-one using sodium acetate. The reaction was performed via three components: β-naphthol, dimedone with various aromatic aldehydes under solvent-free microwave irradiation and conventional heating condition. We observed an efficient result for microwave synthesis than conventional heating. The synthesized tetrahydrobenzo[α]xanthen-11-one (4a–l) was screened for their antimicrobial activity against two bacteria (Escherichia coli and Bacillus subtilis) and two fungal strains (Aspergillus niger and Saccharomyces cerevisiae). The synthesized products: 9, 10-dihydro-9, 9-dimethyl-12-(4-nitrophenyl)-8H-benzo[a]xanthen-11(12H)-one, 9, 10-dihydro-9, 9-dimethyl-12-(2, 4-dichlorophenyl)-8H-benzo[a]xanthen-11(12H)-one, 9, 10-dihydro-9, 9-dimethyl-12-(6-methyl-4-oxo-4H-chromen-3-yl)-8H-benzo[a]xanthen-11(12H)-one exhibit good antimicrobial activity. The developed protocol is graced with appealing advantages such as high purity, simple operation, excellent yields, inexpensive and easy availability of catalyst.

The precursors 2-{[2-(3-fluorophenyl)-4-methyl-1,3-thiazol-5-yl]carbonyl}-N-phenylhydrazinecarbothioamides are synthesized from 2-(3-fluorophenyl)-4-methylthiazole-5-carbohydrazide and aryl isothiocyanates. MW irradiation of the precursors under alkali or acidic conditions led to the products of cyclization 5-[2-(3-fluorophenyl)-4-methylthiazol-5-yl]-N-phenyl-1,3,4-thiadiazol-2-amine or 5-[2-(3-fluorophenyl)-4-methylthiazol-5-yl]-4-phenyl-4H-1,2,4-triazole-3-triiol, accordingly. Structures of the synthesized compounds are confirmed by IR, 1H, and 13C NMR, and mass spectra. All products are tested in vitro for their antibacterial and antifungal activity.

Herein, we report nitrogen-doped TiO

In search for novel compounds targeting Malaria, based on the in silico molecular docking binding affinity data, the novel furans containing pyrazolyl chalcones (3a-d) and pyrazoline derivatives (4a-d) were synthesized. The formation of the synthesized compound were confirmed by spectral analysis like IR, 1H NMR, 13C NMR and mass spectrometry. Compounds with thiophene and pyrazoline ring 4b (0.47 μM), 4c (0.47 μM) and 4d (0.21 μM) exhibited excellent anti-malarial activity against Plasmodium falciparum compared with standard antimalarial drug Quinine (0.83 μM). To check the selectivity furthermore, compounds were tested for antimicrobial activity and none of the synthesized compound exhibited significant potency compared with the standard antibacterial drug Chloramphenicol and antifungal drug Nystatin respectively. So, it can be resolved that the produced compounds show selectively toward antimalarial activity and have the potential to be explored further.

We investigated a novel catalytic application of nickel-doped zinc oxide (Ni-ZnO) nanoparticles and zinc oxide (ZnO) nanoflakes at room temperature in an aqueous hydrotropic solution for the synthesis of biologically active dihydropyrimidones (DHPMs). Ni-ZnO is a stable, recyclable, green, efficient heterogeneous catalyst which shows maximum yield in a shorter reaction time than ZnO nanoflakes in very mild conditions of hydrotropic aqueous medium for DHPMs syntheses.

A set of hierarchical Cd x Zn1−x O nanoflakes (x = 0, 0.01 and 0.03) was prepared by the co-precipitation method using methanol as solvent. The prepared samples were characterized by UV–visible, X-ray diffraction, field emission scanning electron microscopy and energy-dispersive X-ray analysis techniques. The slight red shift in the Cd-doped ZnO confirms the doping of Cd2+ ions into ZnO lattices. The average crystallite size of Cd-doped ZnO nanoflakes was found to be in the range of 10–28 nm. The catalytic activity of Cd-ZnO nanoflakes in conjunction with microwave irradiation was investigated for reactions between o-phenylenediamine with aldehydes. It was found that the presence of Cd content in ZnO promotes rapid and selective synthesis of 2-substituted benzimidazoles under solvent-free conditions. The improvement of the catalytic activity by Cd doping is discussed in the light of the Brunauer–Emmet–Teller method. The catalyst could be reused up to five cycles without any significant loss of catalytic activity.

Synthesis of 4,4'-((phenyl)methylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ol) derivatives was successively carried out using Cu doped ZnO nanomaterials. The nanocrystalline Cu-ZnO was obtained by decomposing as-synthesized copper-zinc oxalate intermediate at 520 °C. The prepared Cu-ZnO nanostructured catalyst was characterized with FTIR, X-ray diffraction, field emission scanning electron microscope and electron diffraction techniques. XRD analysis indicates the formation of highly crystalline hexagonal phase of ZnO along with the presence of monoclinic CuO. FESEM photographs shows the existence of plate like structures made up of small spherical shaped particles having size in the range of 30-50 nm. As-synthesized Cu-ZnO was used as heterogeneous catalyst for one pot synthesis of 4,4'-((phenyl)methylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ol) derivatives using phenyl hydrazine, ethyl acetoacetate and aromatic aldehydes. The 3-methyl-1-phenyl-1H-pyrazol-5-ol was obtained as in-situ precursor to the series of bis-pyrazolone derivatives. The progress of reaction was monitored by thin layer chromatography. The obtained organic product was further characterized and confirmed by FT-IR, 1H-NMR, 13C-NMR and HRMS spectroscopic techniques. The Cu-ZnO catalyst confers upto 96% yield of pyrazolone derivatives in ethanol solvent at refluxing condition. The Cu-ZnO catalyst was used successfully up to 5 cycles without much loss of catalytic activity. Overall, the use of environmental friendly Cu-ZnO nano-structures as a heterogeneous catalyst shows higher yield and lower reaction time towards the synthesis of bispyrazolone derivatives by Tandem Knoevenagel/Michael reaction.

Mycobacterium tuberculosis (Mtb) is an obligate aerobe that is capable of long-term persistence under conditions of low oxygen tension. A series of thiazolyl-pyrazole derivatives (6a–f, 7a–f, 8c, 8e) were screened for antimycobacterial activity against dormant M. tuberculosis H37Ra (D-MTB) and M. bovis BCG (D-BCG). Nine thiazolyl-pyrazole analogs, 6c, 6e, 7a, 7b, 7c, 7e, 7f, 8c and 8e exhibited promissing minimum inhibitory concentration (MIC) values (0.20–28.25 µg/mL) against D-MTB and D-BCG strains of Mtb. Importantly, six compounds (7a, 7b, 7e, 7f, 8c and 8e) exhibited excellent antimycobacterial activity and low cytotoxicity at the maximum evaluated concentration of >250 µg/mL. Finally, the promising antimycobacterial activity and lower cytotoxicity profile suggested that, these compounds could be further subjected for optimization and development as a lead, which could have the potential to treat tuberculosis.

A series of novel 1,3,4-thiadiazoles, 1,2,4-triazoles, and 1,3,4-oxadiazoles were synthesized by cyclization of substituted 1-(2-(2-chlorophenyl)-2-(4-(2,3-dichlorophenyl)piperazin-1-yl)acetyl)thiosemicarbazide. The structures of all newly synthesized compounds were elucidated on the basis of spectral studies. Some of them were screened for their antibacterial activity. The compounds , , , , and have shown moderate activity towards Bacillus Subtilis and Escherichia Coli.

A new series of thiophene anchored 1,3,4-thiadiazole, 1,2,4-triazole, 2-heteryl chromone, 1,5-benzothiazepine, pyrazoline, 2-styryl chromone derivatives containing fluorine are synthesized, characterized by spectral methods and screened them for various biological activities.

Introduction Compounds containing thiadiazole moiety are cognized to possess with variety of clinical and therapeutic activity. Finding a suitable drug target for newly synthesized compounds remain a major bottle neck in current high throughout medicinal chemistry era. Aim To effectively synthesize di substituted thiadiazole compounds and demonstrate drug target identification using an in silico pharmacophore probing approach. Moreover, we also aim to validate the suitability of identified drug target. Materials and methods A cost-effective and environmental friendly chemical synthesis scheme for production of di substituted thiadiazole compounds was employed. Target identification was conducted by Pharmmapper software. Validation was accomplished by performing molecular docking and further Molecular Hydrophobic Potential (MHP) analysis. Results Pharmacophore probing base approach identified hepatocyte growth factor receptor (c-Met) as a suitable biological target for newly synthesized compounds. Binding free energy values indicate that compound 4b, 4e, 4g and 4h has tremendous potential to be further used as lead compound to design selective inhibitors of c-Met receptor. MHP data from current study supports the possibility that hydrophobic contacts might act as major factor stabilizing thiadiazole- c-Met complex. Moreover, in silico observations of current study are in absolute accordance with previously described in vitro and crystallographic analysis. Conclusion We demonstrate that thiadiazole compounds synthesized in current investigation has high potential to act in modulation of hepatocyte growth factor receptor (c-Met) activity and thereby act as putative therapeutic agent in cancer therapy.

A series of novel [4-(1,2,3-thiadiazol-4-yl)phenoxy]methylene anchored 1,3,4-triazoles (8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h) and 1,3,4-thiadiazoles (9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i) were synthesized from thiosemicarbazide (7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j). The structures of these newly synthesized compounds were confirmed on the basis of IR, 1H-NMR, mass spectral techniques, and elemental analysis. The in vitro antimicrobial screenings of the synthesized compounds were carried out against four bacterial pathogens, namely Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, Pseudomonas aeruginosa and three fungal pathogens Candida albicans, Aspergillus niger and Aspergillus clavatus, using broth microdilution minimum inhibitory concentration method. The compounds 7d, 7j, 8a, 9a, 9b, and 9i exhibited promising antibacterial activity against the tested strains, whereas some compounds were found to be active against one of the tested bacterial strains.

A simple, efficient, regioselective, and scalable palladium-catalyzed hydroxycarbonylation of heteroaryl halides to corresponding carboxylic acids using acetic–formic anhydride in presence of Pd(OAc)2, dppf, and diisopropylethyl amine in dimethyl formamide at 80–90 °C in excellent yields.

Variously substituted chalcones were synthesized from 4-difluoromethoxy-dibenzofuran-1-carboxaldehyde. These chalcones were converted into corresponding 3-chlorochromones and dihydro-benzothiazepines. Synthesized compounds were tested for their antifungal, antibacterial, antiviral and antioxidant activities. J. Heterocyclic Chem., (2009).

The reaction of indoline with a substituted benzoyl chloride in the presence of K2CO3 in THF gave compound 4. Compound 4 was subjected to chlorosulphonation to obtain compound 5. Condensation of aromatic amines with compound 5 led to the synthesis of indoline derivatives 6(a-f). Similarly, 5-nitroindoline was treated with a substituted benzoyl chloride to obtain the nitro compound 9, which was reduced using stannous chloride and reacted further with aromatic sulphonyl chloride to obtain the indoline derivatives 11(a-e). These compounds were tested for antibacterial, anti-tuberculosis and antifungal activity. Some of them showed very good activity against some gram-positive and gram negative bacteria, fungal strains and also Mycobacterium tuberculosis. All of the synthesized compounds were subjected to antioxidant activity testing using the in vitro DPPH assay and most of them showed very good activity.

A series of substituted chromones were synthesized and characterized by spectral data. Some of the synthesized compounds were tested for in-vitro antibacterial, antifungal and antioxidant activity. Two compounds have shown very good antioxidant activity and some of the chromone derivatives have exhibited moderate antibacterial and antifungal activity.

A practical, environmentally benign, rapid, and efficient method for the reduction of aromatic azide to amine is described using FeS/aqueous ammonia in the presence of other reducible functionalities. Application of a novel reducing reagent results in aromatic amines with excellent yield and high chemoselectivity, without need of any purification techniques.

New series of 4,4-dimethylbenzopyrano[4,3-d]-1,2,3-selenadiazoles and 4,4-dimethylbenzopyrano-[4,3-d]-1,2,3-thiadiazoles have been synthesized from semicarbazones of chroman-4-one precursors. Some 4-acetyl-2′-acetylamino-2,2-dimethylspiro[chroman-4,5′-2-1,3,4-thiadiazolines] have been synthesized by cyclization of thiosemicarbazones of 2,2-dimethylchroman-4-ones using acetic anhydride. The selected compounds were tested for Phosphotyrosine phosphatase 1B inhibition.

A simple, efficient, regioselective, and scalable palladium-catalyzed hydroxycarbonylation of heteroaryl halides to corresponding carboxylic acids using acetic–formic anhydride in presence of Pd(OAc)2, dppf, and diisopropylethyl amine in dimethyl formamide at 80–90 °C in excellent yields.

Two different strategies, both using a Heck coupling as key reaction, are employed for the synthesis of title compounds (V) and (VIII).

An efficient synthesis of 3-trifluoromethyl-1-(3,4-difluorophenyl)-1H-pyrazol-5(4H)-one (3) and their Knoevenagel condensation reaction with 1,4-diphenyl -1H-pyrazole-3-carbaldehydes 4, 4-oxo-4H-chromene-3-carbaldehydes 6 and 2-chloroquinoline-3-carbaldehydes 8 have been described by using conventional and non-conventional techniques. Comparison of conventional and non-conventional techniques like Microwave , Ultrasonic assisted reactions showed that, the later procedure require shorter reaction time, good yield and was applicable for larger set of substrates emphasizing the importance of eco-friendly conditions.

A series of fluorine containing 4-(substituted-2-hydroxybenzoyl) pyrazoles and pyrazolyl benzo[d]oxazoles were synthesized and evaluated for their antibacterial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis and antifungal activity against Candida albicans. The antibacterial activities were expressed as the minimum inhibitory concentration (MIC50) in microg/ml. The compounds 1-(3,4-difluorophenyl)-4-(5-fluoro-2-hydroxybenzoyl)-1H-pyrazole (4b), oxime derivatives such as 1-(3,4-difluorophenyl)-1H-pyrazol-4-yl)(2-hydroxy-4-methylphenyl)methanone oxime (5b) and (5-chloro-2-hydroxyphenyl)(1-(3,4-difluorophenyl)-1H-pyrazol-4-yl)methanone oxime (5e) exhibited promising activities against tested bacterial strains. Except compound 1-(3,4-difluorophenyl)-4-(2-hydroxybenzoyl)-1H-pyrazole (4d), none of the other compounds showed promising antifungal activity.

Variously substituted chalcones were synthesized from 4-difluoromethoxy-dibenzofuran-1-carboxaldehyde. These chalcones were converted into corresponding 3-chlorochromones and dihydro-benzothiazepines. Synthesized compounds were tested for their antifungal, antibacterial, antiviral and antioxidant activities. J. Heterocyclic Chem., (2009).

A practical, environmentally benign, rapid, and efficient method for the reduction of aromatic azide to amine is described using FeS/aqueous ammonia in the presence of other reducible functionalities. Application of a novel reducing reagent results in aromatic amines with excellent yield and high chemoselectivity, without need of any purification techniques.

Various fluorine containing 4-[-3-(4-aryl)-1-phenyl-1H-pyrazol-4-yl)methylene]-3-(trifluoromethyl)-1-phenyl-1H-pyrazol-5(4H)-one 3a-g and 3-(trifluoromethyl)-4-(4-oxo-4H-chromon-3-yl)methylene-1-phenyl-1H-pyrazol-5(4H)-one 5;i-k have been synthesized by conventional and non-conventional method. The synthesis 3 and 5 highlights a comparative study of conventional, ultrasonication and microwave techniques. All products have been characterized by IR, 1 H NMR, MS study aid screened for their antimicrobial activity.

Acid hydrazide 1 when treated with aryl isothiocyanates gives the compounds 2. These compounds 2 on ultrasound irradiation in acidic medium give compounds 3 i.e. thiadiazoles and in basic medium gives compounds 4 i.e. triazoles. These compounds 2 on treatment with I 2 /KI and NaOH resulted in compounds 5 i.e. oxadiazoles. These compounds are synthesized by conventional method as well as ultra sound irradiation method.