- Microwave Assisted Synthesis of 5-[4-(3-Phenyl-4,5-dihydro-1H-pyrazol-5-yl)phenyl]-1H-tetrazole Derivatives and Their Antimicrobial Activity
-
In the present study, we report the synthesis of 5-[4-(3-phenyl-4,5-dihydro-1H-pyrazol-5-yl)phenyl]-1H-tetrazole derivatives by the Michael addition of chalcones to hydrazine hydrate in presence of acetic acid under conventional heating and microwave irradiation. All the synthesized compounds are characterized by IR, NMR, and mass spectra. The products are screened for their in vitro antimicrobial activity against strains such as Staphylococcus aurous, Bacillus subtilis, Klebsiella pneumonia, Escherichia coli, Aspergillus Niger, Aspergillus flavus, and Fusarium oxysporum. Most of the compounds exhibit high activity.
- Ashok,Nagaraju,Lakshmi, B. Vijaya,Sarasija
-
-
Read Online
- CuO–NiO bimetallic nanoparticles supported on graphitic carbon nitride with enhanced catalytic performance for the synthesis of 1,2,3-triazoles, bis-1,2,3-triazoles, and tetrazoles in parts per million level
-
The unification of CuCl2·2H2O and NiCl2·6H2O with the support of graphitic carbon nitride yielded to form an efficient, synergistic, bimetallic nano-catalyst CuO–NiO@g-C3N4. FT-IR, SEM, TEM
- Gajurel, Sushmita,Dam, Binoyargha,Bhushan, Mayank,Singh, L. Robindro,Pal, Amarta Kumar
-
-
- A Synergistic Magnetically Retrievable Inorganic-Organic Hybrid Metal Oxide Catalyst for Scalable Selective Oxidation of Alcohols to Aldehydes and Ketones
-
Herein, we report a synergistic silica coated magnetic Fe3O4 catalyst functionalized with nitrogen rich organic moieties and immobilized with cobalt metal ion (FNP-5) for selective oxidation of alcohols to aldehydes and ketones using tert-butyl hydroperoxide (TBHP) as oxidant. The catalyst was rigorously characterized via several techniques which delineate its core-shell structure, magnetic behavior, phase and crystal structure. The Co(III) acts as the active catalytic center for selective oxidation reaction. The control reactions revealed radical mechanistic pathway assisted by the synergism induced by the inorganic-organic hybrid nature of FNP-5. The other features of current protocol involve neat reaction conditions, high TOF values, scalability of product and low E-factor value (1.92). Moreover, FNP-5 could be effortlessly separated via an external magnet, displays recyclability over eight catalytic cycles and exhibits structural integrity even after rigorous use. Overall, these results manifest the understanding of synergistic architectures as sustainable surrogates for selective oxidation reactions.
- Mittal, Rupali,Awasthi, Satish Kumar
-
p. 4799 - 4813
(2021/09/30)
-
- The anchoring of a Cu(ii)-salophen complex on magnetic mesoporous cellulose nanofibers: green synthesis and an investigation of its catalytic role in tetrazole reactions through a facile one-pot route
-
Today, most synthetic methods are aimed at carrying out reactions under more efficient conditions and the realization of the twelve principles of green chemistry. Due to the importance and widespread applications of tetrazoles in various industries, especially in the field of pharmaceutical chemistry, and the expansion of the use of nanocatalysts in the preparation of valuable chemical reaction products, we decided to use an (Fe3O4@NFC@NSalophCu)CO2H nanocatalyst in this project. In this study, the synthesis of the nanocatalyst (Fe3O4@NFC@NSalophCu)CO2H was explained in a step-by-step manner. Confirmation of the structure was obtained based on FT-IR, EDX, FE-SEM, TEM, XRD, VSM, DLS, TGA, H-NMR, and CHNO analyses. The catalyst was applied to the synthesis of 5-substituted-1H-tetrazole and 1-substituted-1H-tetrazole derivatives through multi-component reactions (MCRs), and the performance was assessed. With advances in science and technology and increasing environmental pollution, the use of reagents and methods that are less dangerous for the environment has received much attention. Therefore, following green chemistry principles, with the help of the (Fe3O4@NFC@NSalophCu)CO2H salen complex as a nanocatalyst that is recyclable, cheap, safe, and available, the use of water as a green solvent, and reduced reaction times, the synthesis of tetrazoles can be achieved.
- Bagherzade, Ghodsieh,Ghamari kargar, Pouya
-
p. 19203 - 19220
(2021/06/03)
-
- An efficient Cu/functionalized graphene oxide catalyst for synthesis of 5-substituted 1H-tetrazoles
-
The copper nanoparticles (Cu NPs) and amide functionalized graphene oxide (Cu-Amd-RGO) catalyst were prepared. This prepared catalyst (Cu-Amd-RGO) used for the synthesis of tetrazole derivatives. The catalyst (Cu-Amd-RGO) was characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction analysis (XRD). The average particle size of Cu was found to be 7.6?nm. The Cu-Amd-RGO catalyst exhibited excellent catalytic activity and recyclability for synthesis of tetrazoles.
- Kulkarni, Padmakar A.,Satpati, Ashis Kumar,Thandavarayan, Maiyalagan,Shendage, Suresh S.
-
p. 2891 - 2899
(2021/02/12)
-
- Fe3O4@L-lysine-Pd(0) organic–inorganic hybrid: As a novel heterogeneous magnetic nanocatalyst for chemo and homoselective [2 + 3] cycloaddition synthesis of 5-substituted 1H-tetrazoles
-
An efficient and sustainable synthetic protocol has been presented to synthesis and 5-substituted 1H-tetrazole privileged heterocyclic substructures. The synthetic protocol involves two-component reaction between aryl nitriles and NaN3 in water using complex of L-lysine-palladium nanoparticles (NPs) modified Fe3O4 nanoparticles as magnetically separable, recyclable, and reusable heterogeneous catalyst. Magnetically retrievable L-lysine-Pd(0) modified Fe3O4 nanoparticles were applied in [2 + 3] cycloaddition synthesis of 5-substituted 1H-tetrazoles. The advantages of this strategy include easy recovery and efficient reusability of the expensive Pd NPs, obtaining high yields of [2 + 3] cycloaddition, short reaction times, and all of the reported synthetic strategies are being performed in water as green solvent for a wide range of substrates.
- Ashraf, Muhammad Aqeel,Liu, Zhenling,Li, Cheng,Zhang, Dangquan
-
-
- Practical scale up synthesis of carboxylic acids and their bioisosteres 5-substituted-1H-tetrazoles catalyzed by a graphene oxide-based solid acid carbocatalyst
-
Herein, catalytic application of a metal-free sulfonic acid functionalized reduced graphene oxide (SA-rGO) material is reported for the synthesis of both carboxylic acids and their bioisosteres, 5-substituted-1H-tetrazoles. SA-rGO as a catalytic material incorporates the intriguing properties of graphene oxide material with additional benefits of highly acidic sites due to sulfonic acid groups. The oxidation of aldehydes to carboxylic acids could be efficiently achieved using H2O2as a green oxidant with high TOF values (9.06-9.89 h?1). The 5-substituted-1H-tetrazoles could also be effectively synthesized with high TOF values (12.08-16.96 h?1). The synthesis of 5-substituted-1H-tetrazoles was corroborated by single crystal X-ray analysis and computational calculations of the proposed reaction mechanism which correlated well with experimental findings. Both of the reactions could be performed efficiently at gram scale (10 g) using the SA-rGO catalyst. SA-rGO displays eminent reusability up to eight runs without significant decrease in its productivity. Thus, these features make SA-rGO riveting from an industrial perspective.
- Mittal, Rupali,Kumar, Amit,Awasthi, Satish Kumar
-
p. 11166 - 11176
(2021/03/31)
-
- Igneous rock powder as a heterogeneous multi-oxide nano-catalyst for the synthesis of 5-substituted-1H-tetrazoles in polyethylene glycol
-
The use of igneous rock nano-powder as a heterogeneous and recyclable multi-oxide nano-catalyst synthesizing of 5-substituted-1H-tetrazoles is reported. The igneous rock nano-powder was initially prepared by using the ball-milling method. Then, the structure, morphology, and magnetic properties of the prepared igneous rock nano-powder were characterized with some different spectroscopic, microscopic, and thermogravimetric techniques, such as FTIR, FESEM, XRF, XRD, Histogram, and EDS. The instrumental analyses showed that the prepared igneous rock powder is a mixture of metal oxides, such as Si, Al, Ca, Mg, Fe, Na, Mn, and Sr. It showed an excellent catalytic performance in synthesizing of 5-substituted-1H-tetrazoles through [3 + 2] cycloaddition reaction between sodium azide and nitrile compounds. Various aliphatic and aromatic nitriles and sodium azide were reacted in the presence of a catalytic amount of igneous rock nano-powder at 80 o C temperature in PEG-400. The protocol was simple and rapid, with suitable yields of the obtained tetrazoles. The igneous rock nano-powder is readily accessible, reusable, and holds potential for further application in acid-catalyzed organic syntheses and industrial requirements. Graphic abstract: [Figure not available: see fulltext.]
- Javaherian, Mohammad,Movaheditabar, Parviz,Nobakht, Valiollah
-
-
- Synthesis and Photochemical Properties of Manganese(I) Tricarbonyl Diimine Complexes Bound to Tetrazolato Ligands
-
Ten manganese(I) tricarbonyl diimine complexes bound to variably functionalised 5-aryl-tetrazolato ligands were prepared, and their photochemical properties were investigated. Upon exposure to light at 365 nm, each complex decomposed to its free diimine and tetrazolato ligands, simultaneously dissociating three CO ligands, as evidenced by changes in the IR spectra of the irradiated complexes over time. The anti-bacterial properties of one of these complexes were tested against Escherichia coli. While the complex displayed no effect on the bacterial growth in the dark, pre-irradiated solutions inhibited bacterial growth. Comparative studies revealed that the antibacterial properties originate from the presence of free 1,10-phenanthroline.
- Stout, Matthew J.,Stefan, Alessandra,Skelton, Brian W.,Sobolev, Alexandre N.,Massi, Massimiliano,Hochkoeppler, Alejandro,Stagni, Stefano,Simpson, Peter V.
-
supporting information
p. 292 - 298
(2020/01/25)
-
- Discovery and optimization of 4-oxo-2-thioxo-thiazolidinones as NOD-like receptor (NLR) family, pyrin domain-containing protein 3 (NLRP3) inhibitors
-
Aberrant activation of NLRP3 inflammasome is present in a subset of acute and chronic inflammatory diseases. The NLRP3 inflammasome has been recognized as an attractive therapeutic target for developing novel and specific anti-inflammatory inhibitors. Cellular structure-activity relationship-guided optimization resulted in the identification of 4-oxo-2-thioxo-thiazolidinone derivative 9 as a selective and direct small-molecule inhibitor of NLRP3 with IC50 of 2.4 μM, possessing favorable ex vivo and in vivo pharmacokinetic properties. Compound 9 may represent a lead for the development of anti-inflammatory therapeutics for treating NLRP3-driven diseases.
- Chen, Yun,Deng, Xianming,He, Hongbin,Hu, Zhiyu,Huang, Huiying,Jiang, Hua,Li, Li,Xu, Qingyan,Zhou, Rongbin
-
supporting information
(2020/02/15)
-
- Copper(II)-faciliated synthesis of substituted thioethers and 5-substituted 1H-tetrazoles: Experimental and theoretical studies
-
Benzoylhydrazine based Schiff base-ligated two new copper(II) complexes, [Cu(L1)2] (1) and [Cu(L2)2] (2) were synthesized by the reaction of Cu(CH3COO)2·H2O with respective Schiff base ligand 1-[(4-nitrophenyl)ethylidene] benzohydrazide (HL1) or 1-[(4-methoxyphenyl)ethylidene] benzohydrazide (HL2). Both complexes were isolated as greenish solid and fully characterized by elemental analysis, FT-IR, EPR, thermo-gravimetric (TG) analysis and Cyclic Voltammetry. The molecular structures of both complexes have also been determined by single crystal X-ray crystallography, which confirmed the coordination of Schiff base ligands through N, O donor atoms and distorted square planar geometry around the Cu(II) ion. Both complexes were found to be good homogeneous catalysts for the synthesis of a wide range of substituted thioethers and 5-substituted 1H-tetrazoles in 92% and 93% yield, respectively, at a low catalyst loading (0.5 mol%). The bond angles and distances, as discerned from the DFT calculations, commusurated with the experimental findings. The energy difference between the HOMO and the LUMO, calculated from DFT studies, was found to be 5.645 eV and 6.459 eV for complex 1 and complex 2, respectively. These results are in harmony with the observed higher catalytic activity of complex 1.
- Layek, Samaresh,Agrahari, Bhumika,Dey, Shuvankar,Ganguly, Rakesh,Pathak, Devendra D.
-
p. 194 - 206
(2019/06/24)
-
- Enhanced Thermocatalytic Activity of Porous Yellow ZnO Nanoflakes: Defect- and Morphology-Induced Perspectives
-
Herein, we report a simple and effective strategy for the synthesis of yellow ZnO (Y-ZnO) nanostructures with abundant oxygen vacancies on a large scale, through the sulfidation of ZnO followed by calcination. The developed strategy allows retention of the overall morphology of Y-ZnO compared with pristine ZnO and the extent of oxygen vacancies can be tuned. The influence of oxygen deficiencies, the extent of defect sites, and the morphology of ZnO on its solution-phase thermocatalytic activity has been evaluated in the synthesis of 5-substituted-1H-tetrazoles with different nitriles and sodium azide. A reasonable enhancement in the reaction rate was achieved by using Y-ZnO nanoflakes (Y-ZnO NFs) as a catalyst in place of pristine ZnO NFs. The reaction was complete within 6 h at 110 °C with Y-ZnO NFs, whereas it took 14 h at 120 °C with pristine ZnO NFs. The catalyst is easy to recycle without a significant loss in catalytic activity.
- Galani, Sunil M.,Panda, Asit Baran
-
p. 612 - 620
(2019/02/14)
-
- Design and Synthesis of Poly(ADP-ribose) Polymerase Inhibitors: Impact of Adenosine Pocket-Binding Motif Appendage to the 3-Oxo-2,3-dihydrobenzofuran-7-carboxamide on Potency and Selectivity
-
Poly(adenosine 5′-diphosphate-ribose) polymerase (PARP) inhibitors are a class of anticancer drugs that block the catalytic activity of PARP proteins. Optimization of our lead compound 1 ((Z)-2-benzylidene-3-oxo-2,3-dihydrobenzofuran-7-carboxamide; PARP-1 IC50 = 434 nM) led to a tetrazolyl analogue (51, IC50 = 35 nM) with improved inhibition. Isosteric replacement of the tetrazole ring with a carboxyl group (60, IC50 = 68 nM) gave a promising new lead, which was subsequently optimized to obtain analogues with potent PARP-1 IC50 values (4-197 nM). PARP enzyme profiling revealed that the majority of compounds are selective toward PARP-2 with IC50 values comparable to clinical inhibitors. X-ray crystal structures of the key inhibitors bound to PARP-1 illustrated the mode of interaction with analogue appendages extending toward the PARP-1 adenosine-binding pocket. Compound 81, an isoform-selective PARP-1/-2 (IC50 = 30 nM/2 nM) inhibitor, demonstrated selective cytotoxic effect toward breast cancer gene 1 (BRCA1)-deficient cells compared to isogenic BRCA1-proficient cells.
- Velagapudi, Uday Kiran,Langelier, Marie-France,Delgado-Martin, Cristina,Diolaiti, Morgan E.,Bakker, Sietske,Ashworth, Alan,Patel, Bhargav A.,Shao, Xuwei,Pascal, John M.,Talele, Tanaji T.
-
p. 5330 - 5357
(2019/06/07)
-
- KIT-6-anchored sulfonic acid groups as a heterogeneous solid acid catalyst for the synthesis of aryl tetrazoles
-
In the current study, a simple, environmentally benign and cost-effective method is presented for the preparation of 5-substituted-1H-aryltetrazoles. To this goal, mesoporous KIT-6 silica anchored with sulfonic acid (–SO3H) groups via post-grafting modification was synthesized using the sol–gel method and characterized by XRD, TGA, FTIR, BET, TEM and SEM techniques. For the preparation of tetrazole derivatives, the effect of various parameters such as catalyst amount, aryl nitrile:azide ratio, temperature and reaction time was tested. The hybrid organic/inorganic catalyst could be recovered easily through a simple filtration and reused multiple times without significant loss in activity.
- Najafi Chermahini, Alireza,Andisheh, Nikzad,Teimouri, Abbas
-
p. 831 - 838
(2018/03/01)
-
- Microwave-assisted synthesis of 1H-tetrazole-based flavonoid derivatives and their antimicrobial activity
-
A series of novel tetrazole scaffolds containing chalcones 4a–e and aurones 5a–e were synthesized under conventional and microwave irradiation conditions. All the newly synthesized compounds were characterized by IR, NMR and mass spectral data. Furthermor
- Ashok, Dongamanti,Nagaraju, Nalaparaju,Sarasija, Madderla,Vijaya Lakshmi
-
p. 1305 - 1313
(2019/01/05)
-
- Conversion of Arylboronic Acids to Tetrazoles Catalyzed by ONO Pincer-Type Palladium Complex
-
A convenient synthesis of a library of tetrazoles through a novel and operationally simple protocol effecting the direct conversion of arylboronic acids catalyzed by a new ONO pincer-type Pd(II) complex under mild reaction conditions using the readily available reagents is reported. The palladium complex was reused up to four cycles in an open-flask condition.
- Vignesh, Arumugam,Bhuvanesh, Nattamai S. P.,Dharmaraj, Nallasamy
-
p. 887 - 892
(2018/06/15)
-
- Synthesis of Aldehydes by Organocatalytic Formylation Reactions of Boronic Acids with Glyoxylic Acid
-
Reported herein is a conceptually novel organocatalytic strategy for the formylation of boronic acids. New reactivity is engineered into the α-amino-acid-forming Petasis reaction occurring between aryl boronic acids, amines, and glyoxylic acids to prepare aldehydes. The operational simplicity of the process and its ability to generate structurally diverse and valued aryl, heteroaryl, and α,β-unsaturated aldehydes containing a wide array of functional groups, demonstrates the practical utility of the new synthetic strategy.
- Huang, He,Yu, Chenguang,Li, Xiangmin,Zhang, Yongqiang,Zhang, Yueteng,Chen, Xiaobei,Mariano, Patrick S.,Xie, Hexin,Wang, Wei
-
supporting information
p. 8201 - 8205
(2017/06/30)
-
- Syntheses of 5-substituted 1H-tetrazoles catalyzed by reusable Cu(II)-NaY zeolite from nitriles
-
Cu(II)-NaY heterogeneous catalyst is used for the synthesis of 5-substituted 1H-tetrazoles by [2+3]-cycloaddition of sodium azide and nitriles. The salient features of this process are low reaction times, mild reaction conditions and high yields. The catalyst is recovered and reused for several cycles with consistent activity.
- Sudhakar,Purna Chandra Rao,Prem Kumar,Suresh,Ravi
-
p. 864 - 866
(2017/02/10)
-
- Synthesis of 5-substituted-1H-tetrazole derivatives using monodisperse carbon black decorated Pt nanoparticles as heterogeneous nanocatalysts
-
A facile and highly efficient protocol for synthesis of new 5-substituted 1H-tetrazoles derivatives has been developed by the assistance of vulcan carbon decorated based on monodisperse platinum nanoparticles (Pt NPs@VC) as superior and recyclable heterog
- Baskaya, Gaye,Esirden, Ibrahim,Erken, Esma,Sen, Fatih,Kaya, Muharrem
-
p. 1992 - 1999
(2017/01/28)
-
- Microwave assisted synthesis of novel tetrazole/sulfonamide derivatives based on octahydroacridine, xanthene and chromene skeletons as inhibitors of the carbonic anhydrases isoforms I, II, IV and VII
-
The synthesis of novel tetrazole/sulfonamide derivatives based on octahydroacridine, xanthene and chromene scaffold by using microwave (MW) assisted techniques is reported in this study. These synthesized hybrid compounds were assayed for the inhibition o
- Esirden, ?brahim,Tan?, Muhammet,Supuran, Claudiu T.,Kaya, Muharrem
-
supporting information
p. 86 - 89
(2016/12/09)
-
- [Cu(phen)(PPh3)2]NO3-catalyzed microwave-assisted green synthesis of 5-substituted 1H-tetrazoles
-
Abstract: An efficient synthetic methodology for construction of 5-substituted 1H-tetrazoles under microwave irradiation in green medium is described. With [Cu(phen)(PPh3)2]NO3 as catalyst and H2O-isopropyl alcohol (IPA) as reaction medium, various substituted nitriles underwent (3?+?2) cycloaddition reaction with NaN3 under microwave irradiation to provide corresponding 5-substituted 1H-tetrazoles in high yield. This method is not only efficient and general but also benefits from high functional group tolerance. This environmentally friendly synthetic methodology is visualized as an alternative to existing procedures, providing a simple route to privileged scaffolds.
- Padmaja,Meena,Maiti, Barnali,Chanda, Kaushik
-
p. 7365 - 7374
(2017/09/06)
-
- RETRACTED ARTICLE: A rapid and novel method for the synthesis of 5-substituted 1H-tetrazole catalyzed by exceptional reusable monodisperse Pt NPs@AC under the microwave irradiation
-
A series of 5-substituted 1H-tetrazoles were synthesized in DMF by the [3 + 2] cycloaddition reaction under the effect of microwave irradiation (10-30 min, fixed mode, 90 °C, 140 W) in the presence of highly efficient superior catalyst. For this reaction,
- Erken, Esma,Esirden, Ibrahim,Kaya, Muharrem,Sen, Fatih
-
p. 68558 - 68564
(2015/09/01)
-
- RETRACTED ARTICLE: Monodisperse Pt NPs@rGO as highly efficient and reusable heterogeneous catalysts for the synthesis of 5-substituted 1H-tetrazole derivatives
-
Monodisperse platinum nanoparticles supported on reduced graphene oxide (Pt NPs@rGO) are stable, isolable, bottleable, long-lived, highly efficient and exceptionally reusable heterogeneous catalysts for the synthesis of 5-substituted 1H-tetrazoles from so
- Esirden, Ibrahim,Erken, Esma,Kaya, Muharrem,Sen, Fatih
-
p. 4452 - 4457
(2015/09/01)
-
- Synthetic application of gold nanoparticles and auric chloride for the synthesis of 5-substituted 1H-tetrazoles
-
An effective one-pot, convenient gold catalyzed synthesis of 5-substituted 1H-tetrazoles has been discussed. The study demonstrated the comparative overview for utilization of gold(iii) and gold nano-particles (spheres) as a catalyst. Detailed understandi
- Kumar, Satyanand,Kumar, Arvind,Agarwal, Alka,Awasthi, Satish Kumar
-
p. 21651 - 21658
(2015/03/30)
-
- Facile, highly efficient and novel method for synthesis of 5-substituted 1H-tetrazoles catalysed by copper(I) chloride
-
The present study on tetrazole compounds, which have a wide area of application, proposes a new, simple and highly effective method. A series of 5-substituted 1H-tetrazoles were synthesised in DMF via the [3 + 2] cycloaddition reaction, in which different
- Esirden, Ibrahim,Ba?ar, Erhan,Kaya, Muharrem
-
p. 1231 - 1236
(2015/06/23)
-
- Application of a functionalized mesoporous silica catalyst to the synthesis of tetrazoles
-
In the present study, well ordered MCM-41 was synthesized and functionalized with benzyl group and subsequently sulfonated with chlorosulfonic acid. The functionalized catalyst (MCMBSA) was characterized by XRD, TGA, FTIR, TEM, BET, and SEM. 5-Aryl-1H-tetrazoles were synthesized by the reaction of the corresponding aryl nitriles and sodium azide catalyzed by MCMBSA. The mole ratio of nitrile to sodium azide, the amount of catalyst, reaction times, and solvent type were optimized. The MCMBSA catalyst was more effective than the catalyst obtained from the direct sulfonation of MCM-41. The versatility of the method was investigated by using various nitriles, which showed reasonable yields of tetrazoles. The regeneration and reusability of catalyst was also examined.
- Najafi Chermahini, Alireza,Khani Omran, Masoud,Dabbagh, Hossein A.,Mohammadnezhad, Gholamhossein,Teimouri, Abbas
-
p. 4814 - 4820
(2015/06/16)
-
- Synthesis of New Tetrazole Derivatives of Spiro- and Bis-barbiturates
-
This work described the synthesis of the first and unprecedented examples of 5-aryl-1H-tetrazoles including spiro- and bis-(thio)barbiturates, generated from the reaction between 4-(1H-tetrazol-5-yl)benzaldehyde with (thio)barbituric acids and cyanogen br
- Kashani, Elmira,Pesyan, Nader Noroozi,Sahin, Ertan
-
p. 959 - 967
(2015/12/01)
-
- Rectangular ZnO porous nano-plate assembly with excellent acetone sensing performance and catalytic activity
-
The controlled synthesis of a hierarchically assembled porous rectangular ZnO plate (2.5-3.5 μm length, 1.5-2.5 μm width and 100-150 nm thickness) from bulk ZnO without using any organic substrates, such as solvents/surfactants/structure-directing agents, is presented. The synthesized ZnO plates are single crystalline with exposed (1010) facets on the flat surface, porous and formed through the calcination of a hydrozincite [Zn5(CO3)2(OH)6] intermediate. A gas sensor based on the synthesized porous ZnO architecture exhibited high sensitivity towards acetone even in low concentration (S = 3.4 in 1 ppm acetone) with good selectivity. The ZnO nanostructured material as a heterogeneous catalyst also showed excellent catalytic activity for the synthesis of 5-substituted-1H-tetrazoles (yield = 94%). Both the activities are superior than those of other reported ZnO based acetone sensors and heterogeneous catalysts. We believe that the improved properties of the synthesized ZnO nanostructure is due to the exposed (1010) facets, and its porous and assembled structure, which provides a reasonably large accessible surface area, and facilitates diffusion and mass transport of gas or substrate molecules.
- Giri, Arnab Kanti,Saha, Arka,Mondal, Aniruddha,Chandra Ghosh, Subhash,Kundu, Susmita,Panda, Asit Baran
-
p. 102134 - 102142
(2015/12/11)
-
- Tetrazoles: Calcium oxalate crystal growth modifiers
-
Molecules containing tetrazole substituents have become of interest due to their being bioisosteres of carboxylic acids and like their carboxylate counterparts, tetrazolate anions have been able to affect the crystal growth of barium sulphate and calcium carbonate. In this proof of principle study, we show that this behaviour also extends to calcium oxalate and therefore opens the possibility of using tetrazole-based additives for investigating mineralization processes of human pathological relevance. This journal is
- McMulkin, Calum J.,Massi, Massimiliano,Jones, Franca
-
p. 2675 - 2681
(2015/03/30)
-
- Silica supported lanthanum triflate mediated synthesis of 5-substituted-1H tetrazoles
-
Silica supported lanthanum triflate (Ln(OTf)3-SiO2) promoted synthesis of 5-substituted 1H-tetrazoles via [3+2] cycloaddition between aromatic/heteroaromatic nitriles and sodium azide is a high product yielding, facile, and straightf
- Meshram, Gangadhar A.,Deshpande, Shruti S.,Wagh, Pramod A.,Vala, Vipul A.
-
p. 3557 - 3560
(2014/06/10)
-
- SUBSTITUTED TRICYCLIC COMPOUNDS WITH ACTIVITY TOWARDS EP1 RECEPTORS
-
The present invention belongs to the field of EPl receptor ligands. More specifically it refers to compounds of general formula (I) having great affinity and selectivity for the EPl receptor. The invention also refers to the process for their preparation, to their use as medicament for the treatment and/or prophylaxis of diseases or disorders mediated by the EPl receptor as well as to pharmaceutical compositions comprising them.
- -
-
Page/Page column 70; 71
(2013/10/22)
-
- SUBSTITUTED TRICYCLIC COMPOUNDS WITH ACTIVITY TOWARDS EP1 RECEPTORS
-
The present invention belongs to the field of EP1 receptor ligands. More specifically it refers to compounds of general formula (I) having great affinity and selectivity for the EP1 receptor. The invention also refers to the process for their preparation, to their use as medicament for the treatment and/or prophylaxis of diseases or disorders mediated by the EP1 receptor as well as to pharmaceutical compositions comprising them.
- -
-
Page/Page column 129; 130
(2013/10/22)
-
- The synthesis of 5-substituted 1H-tetrazoles in molten tetrabutylammonium bromide
-
An economical and environmentally benign method for the synthesis of 5-substituted 1H-tetrazoles has been established. In this protocol, molten tetrabutylammonium bromide (TBAB) is used as both the solvent and catalyst. A mechanism involving the intermedi
- Xie, Aming,Cao, Meiping,Feng, Liandong,Dong, Wei
-
p. 665 - 667
(2014/01/17)
-
- Zeolite and sulfated zirconia as catalysts for the synthesis of 5-substituted 1H-tetrazoles via [2+3] cycloaddition of nitriles and sodium azide
-
The [2+3] cycloaddition between various nitriles and sodium azide proceeds smoothly in the presence of zeolite and sulfated zirconia as effective catalysts, in water and DMF/MeOH, to give the corresponding 5-substituted 1H-tetrazoles in good to high yields. The reaction most probably proceeds through the in situ formation of catalyst azide species, followed by a successive [2+3] cycloaddition with the nitriles. This method has the advantages of high yields, simple methodology and easy work-up. The catalyst can be recovered by simple filtration and reused with good yields.
- Teimouri, Abbas,Najafi Chermahini, Alireza
-
experimental part
p. 2606 - 2610
(2011/10/09)
-
- Simple and efficient synthesis of 5-substituted 1-H-tetrazoles using metal-modified clay catalysts
-
The synthesis of 5-substituted 1-H-tetrazoles based on reaction of a series of aromatic nitriles with sodium azide was investigated. The reaction was catalyzed by modified montmorillonite K-10 including Cu2+, Fe 3+, Ni2+, and Zn2+ metal ions. The best results obtained by Mont-K10-Cu catalyst. The catalysts were reused several times without loss of their activity. The present procedure offers advantages such as a shorter reaction time, simple workup, recovery, and reusability of the catalyst.
- Chermahini, Alireza Najafi,Teimouri, Abbas,Moaddeli, Ali
-
experimental part
p. 168 - 173
(2011/10/08)
-
- Highly efficient synthesis of 5-substituted 1H-tetrazoles catalyzed by Cu-Zn alloy nanopowder, conversion into 1,5- and 2,5-disubstituted tetrazoles, and synthesis and NMR studies of new tetrazolium ionic liquids
-
A series of 5-substituted 1H-tetrazoles were synthesized through [3+2] cycloaddition reactions between nitriles RCN and NaN3 in the presence of Cu-Zn alloy nanopowder as catalyst. The 1,5-dibutyl, 1-butyl-5-hexyl, 2,5-dibutyl, and 2-butyl-5-hexyl derivatives were then used as building blocks to synthesize several novel tetrazolium ionic liquids (ILs) with EtSO 4-, OTf-, and NTf2- counterions. Whereas alkylation of the 2,5-dialkyltetrazoles selectively gave the N-4 alkylated onium salts, with the 1,5-dialkyl derivatives approximately 1:1 mixtures of two tetrazolium salts were formed by alkylation at N-3 and N-4. The triflate and ethyl sulfate salts are room-temperature ILs that are hydrophilic, whereas the NTf2 salts are low-melting ILs and are hydrophobic. The resulting tetrazolium-based ionic liquids were studied by various multinuclear and 2D NMR techniques including natural abundance 15N and 1H/15N correlations.
- Aridoss, Gopalakrishnan,Laali, Kenneth K.
-
experimental part
p. 6343 - 6355
(2011/12/03)
-
- Clay-catalyzed synthesis of 5-substituent 1-H-tetrazoles
-
In this study, the possibility of 5-substituted 1-H-tetrazoles synthesis using clays as catalyst was investigated. The reaction of a series of aromatic nitriles with sodium azide was catalyzed by montmorillonite K-10 or kaolin clays in water or DMF as solvent. Conventional heating or ultrasonic irradiation was used to promote reaction. The amount of nitrile to sodium azide mole ratio, amount of catalyst, reaction time, and solvent type were optimized. The versatility of this method was checked by using various nitriles, which showed reasonable yields of tetrazole formation. It was found that using nitriles with electron-with-drawing groups result in both higher yields and lower reaction times. The catalysts could be reused several times without significant loss of their catalytic activity. Compared to conventional heating, ultrasonic irradiation reduced reaction times and increased catalyst activity. The present procedure is green and offers advantages, such as shorter reaction time, simple workup, and recovery and reusability of catalyst.
- Chermahini, Alireza Najafi,Teimouri, Abbas,Momenbeik, Fariborz,Zarei, Amin,Dalirnasab, Zeinab,Ghaedi, Aseyeh,Roosta, Mostafa
-
experimental part
p. 913 - 922
(2010/09/03)
-
- A simple, advantageous synthesis of 5-substituted 1 h -tetrazoles
-
An advantageous synthesis of 5-substituted 1H-tetrazoles has been developed by treatment of organic nitriles with NaN3 in the presence of iodine or the heterogeneous catalyst, silica-supported sodium hydrogen sulfate (NaHSO4SiO2). Georg Thieme Verlag Stuttgart New York.
- Das, Biswanath,Reddy, Cheruku Ravindra,Kumar, Duddukuri Nandan,Krishnaiah, Martha,Narender, Ravirala
-
experimental part
p. 391 - 394
(2010/04/24)
-
- Tetrazoles: A new class of compound for crystallization modification
-
Tetrazoles are a class of organic compound often used as carboxylic acid analogues. This analogous behaviour is shown to extend to crystallization modification, that is, tetrazoles are also able to influence crystal growth and morphology although in a dif
- Massi, Massimiliano,Ogden, Mark I.,Radomirovic, Tomoko,Jones, Franca
-
body text
p. 4205 - 4207
(2011/07/08)
-
- Cadmium chloride as an efficient catalyst for neat synthesis of 5-substituted 1H-tetrazoles
-
Cadmium chloride (CdCl2) has been found to be an efficient catalyst for a neat [2+3]-cycloaddition of NaN3 with nitriles to afford 5-substituted 1H-tetrazoles in good yields. The shorter reaction times, greater yields of the product, and easy workup are the advantages of this methodology.
- Venkateshwarlu,Premalatha,Rajanna,Saiprakash
-
experimental part
p. 4479 - 4485
(2010/04/29)
-
- Antimony trioxide as an efficient Lewis acid catalyst for the synthesis of 5-substituted 1H-tetrazoles
-
Sb2O3 was found to be effective as a catalyst for a smooth (2 + 3) cycloaddition of sodium azide with nitriles to afford 5-substituted 1H-tetrazoles in good yields. Copyright Taylor & Francis Group, LLC.
- Venkateshwarlu,Rajanna,Saiprakash
-
experimental part
p. 426 - 432
(2009/05/30)
-
- Zinc hydroxyapatite - Catalyzed efficient synthesis of 5-substituted 1H-tetrazoles
-
Zinc hydroxyapatite (ZnHAP) is an effective heterogeneous catalyst for the (2 + 3)-cycloaddition of sodium azide with nitriles to afford 5-substituted 1H-tetrazoles in good yields. The catalyst is recovered and reused for several cycles with consistent ac
- Lakshmi Kantam,Balasubrahmanyam,Shiva Kumar
-
p. 1809 - 1814
(2007/10/03)
-
- Nanocrystalline ZnO as an efficient heterogeneous catalyst for the synthesis of 5-substituted 1H-tetrazoles
-
Nanocrystalline ZnO is an effective heterogeneous catalyst for the [2 + 3]-cycloaddition of sodium azide with nitriles to afford 5-substituted 1H-tetrazoles in good yields.
- Lakshmi Kantam,Shiva Kumar,Sridhar
-
p. 1212 - 1214
(2007/10/03)
-
- Anti-inflammatory piperazinyl-benzyl-tetrazole derivatives and intermediates thereof
-
This invention relates to tetrazoles and their pharmaceutically acceptable salts which are selective agonists for the delta opioid receptor, particularly useful in the treatment of inflammatory diseases such as arthritis, psoriasis, asthma, inflammatory bowel disease, disorders or respiratory function, gastrointestinal disorders such as functional bowel disease and functional GI disorders, of formula (I) wherein R1is H, C2-C6alkanoyl, C1-C6alkyl, C2-C6alkenyl, C2-C6alkynyl, (C3-C7cycloalkyl)-(C1-C4alkyl), (C1-C4alkoxy)-(C1-C4alkyl), carboxy-(C1-C4alkyl), aryl-(C1-C4alkyl) or heteroaryl-(C1-C4alkyl); R2and R3are each independently H or C1-C4alkyl; R4is selected from (i) H, (ii) a group of the formula R6—(CH2)m—Z—(CH2)n—, where m is 0, 1, 2 or 3, n is 1, 2 or 3, Z is a direct link or O, and R6is —CO2H or —CO2(C1-C4alkyl), and (iii) a group of formula (a) where R7is H or C1-C4alkyl; and R5is hydroxy, C1-C4alkoxy or —NHSO2(C1-C4alkyl); with the proviso that when Z is O, m is 1, 2 or 3 and n is 2 or 3.
- -
-
-
- Pyrimidine derivatives and processes for the preparation thereof
-
4-Amino-1H-pyrazolo[3,4-d]pyrimidine derivatives of formula I wherein the substituents are as defined in claim 1, are described.These compounds inhibit the tyrosine kinase activity of the receptor for epidermal growth factor (EGF) and c-erbB2 kinase and can be used as anti-tumor agents.
- -
-
-
- 2-Benzyloxymethyl-5-(tributylstannyl)tetrazole. A reagent for the preparation of 5-aryl- and 5-heteroaryl-1H-tetrazoles via the Stille reaction
-
2-Benzyloxymethyl-5-(tributylstannyl)tetrazole (2) is a useful reagent for the conversion of aryl- and heteroarylhalides (bromides and iodides) to 5-aryl- and 5-heteroaryl-1H-tetrazoles. The conversion entails a copper(I) iodide co-catalyzed Stille palladium-catalyzed cross-coupling reaction and a N-benzyloxymethyl deprotection step. Coupling was possible with electron neutral and electron poor substrates in yields ranging from 35-93%. (C) 2000 Elsevier Science Ltd.
- Bookser, Brett C.
-
p. 2805 - 2809
(2007/10/03)
-
- ANTIVIRALLY ACTIVE HETEROCYCLIC AZAHEXANE DERIVATIVES
-
There are described compounds of formula I*, STR1 wherein R. sub.1 is lower alkoxycarbonyl,R 2 is secondary or tertiary lower alkyl or lower alkylthio-lower alkyl, R. sub.3 is phenyl that is unsubstituted or substituted by one or more lower alkoxy radicals, or C 4-C 8 cycloalkyl,R. sub.4 is phenyl or cyclohexyl each substituted in the 4-position by unsaturated heterocyclyl that is bonded by way of a ring carbon atom, has from 5 to 8 ring atoms, contains from 1 to 4 hetero atoms selected from nitrogen, oxygen, sulfur, sulfinyl (--SO--) and sulfonyl (--SO 2--) and is unsubstituted or substituted by lower alkyl or by phenyl-lower alkyl,R 5, independently of R 2, has one of the meanings mentioned for R 2, andR 6, independently of R. sub.1, is lower alkoxycarbonyl,or salts thereof, provided that at least one salt-forming group is present. The compounds are inhibitors of retroviral aspartate protease and can be used, for example, in the treatment of AIDS. They exhibit outstanding pharmacodynamic properties.
- -
-
-
- New aza-dipeptide analogues as potent and orally absorbed HIV-1 protease inhibitors: Candidates for clinical development
-
On the basis of previously described X-ray studies of an enzyme/aza- dipeptide complex, aza-dipeptide analogues carrying N-(bis-aryl-methyl) substituents on the (hydroxethyl)hydrazine moiety have been designed and synthesized as HIV-1 protease inhibitors. By using either equally (12) or orthogonally (13) protected dipeptide isosteres, symmetrically and asymmetrically acylated aza-dipeptides can be synthesized. This approach led to the discovery of very potent inhibitors with antiviral activities (ED50) in the subnanomolar range. Acylation of the (hydroxethyl)hydrazine dipeptide isostere with the L-tert-leucine derivative 29 increased the oral bioavailability significantly when compared to the corresponding L-valine or L-isoleucine derivatives. The bis (L-tert-leucine) derivatives CGP 75355, CGP 73547, CGP 75136, and CGP 75176 combine excellent antiviral activity with high blood concentration after oral administration. Furthermore, they show no cross-resistance with saquinavir-resistant strains and maintain activity against indinavir-resistant ones. Consequently they qualify for further profiling as potential clinical candidates.
- Bold, Guido,F?ssler, Alexander,Capraro, Hans-Georg,Cozens, Robert,Klimkait, Thomas,Lazdins, Janis,Mestan, Jürgen,Poncioni, Bernard,R?sel, Johannes,Stover, David,Tintelnot-Blomley, Marina,Acemoglu, Figan,Beck, Werner,Boss, Eugen,Eschbach, Martin,Hürlimann, Thomas,Masso, Elvira,Roussel, Serge,Ucci-Stoll, Katharina,Wyss, Dominique,Lang, Marc
-
p. 3387 - 3401
(2007/10/03)
-