http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2013 , Hindawi Publishing Corporation . All rights reserved. Sun, 12 May 2013 10:51:03 +0000 http://www.hindawi.com/journals/oci/2013/659107/ A multicomponent one-pot clean cyclocondensation reaction of 4-chloro-2-nitro aniline/amino acids and aromatic aldehydes/indole-2,3-diones with thiosemicarbazide in water yielding triazole/spiro indole-triazole derivatives in high yields and shorter reaction time and displaying excellent florescent property is reported. The developed MCR may provide a valuable practical tool for the synthesis of new drugs containing the title core fragment. All the newly synthesized compounds have been characterized by IR, 1HNMR, 13CNMR, and fluorescence study and also been screened for antimicrobial activity. Harshita Sachdeva, Rekha Saroj, Sarita Khaturia, and Diksha Dwivedi Copyright © 2013 Harshita Sachdeva et al. All rights reserved. Thu, 02 May 2013 13:49:04 +0000 http://www.hindawi.com/journals/oci/2013/127585/ ,-unsaturated aldehydes and ketones are regioselectively reduced to the corresponding allylic alcohols with /Ba system in CH3CN. This system is also efficient for the chemoselective reduction of enals in the presence of enones at room temperature. Mina Mohamadi, Davood Setamdideh, and Behrooz Khezri Copyright © 2013 Mina Mohamadi et al. All rights reserved. Sun, 17 Mar 2013 17:02:55 +0000 http://www.hindawi.com/journals/oci/2013/210474/ This review article deals with synthesis and reactions of benzo[1,5]thiazepines and the related derivatives and their applications, biological activity as well as spectroscopic data. Most of the reported data on the methods of synthesis, chemical reactions, and biological activity of these heterocycles published over the last ten years are reviewed in this paper. Khairy A. M. El-Bayouki Copyright © 2013 Khairy A. M. El-Bayouki. All rights reserved. Thu, 14 Mar 2013 19:13:18 +0000 http://www.hindawi.com/journals/oci/2013/163028/ Artemisia annua L. (Asteraceae) is an annual herb native of Asia. This plant has been used for many centuries in traditional Chinese medicine for the treatment of fever and malaria. Conventional methods for the extraction of artemisinin from A. annua including solvent extraction, Soxhlet extraction, and heat reflux extraction are characterized by long extraction times and the consumption of large volume of solvents. A simple, rapid, and precise microwave-assisted extraction process was optimized for fast sample preparation for the faster quantitative determination of artemisinin, potential new generation antimalarial drug, from dried leaves of Artemisia annua L. A simple experiment was designed for the optimization of the appropriate solvent under same extraction conditions. The selected appropriate solvent was then standardized for various different extraction variables. The major parameters studied showed effects on extraction efficiency including processing time, strength of microwave, moisture content, volume and nature of the solvent. The most favorable conditions were obtained by using plant material of 25 mesh (particle size) extracted with acetone for 120 seconds at 160 W (i.e., 20% of total power). Quantitative analysis was performed using thin-layer chromatography coupled with a densitometer (TLC densitometry). The results showed that MAE can be used as an efficient and rapid method for the extraction of the active components from plants. Himanshu Misra, Darshana Mehta, B. K. Mehta, and D. C. Jain Copyright © 2013 Himanshu Misra et al. All rights reserved. Thu, 14 Feb 2013 17:49:23 +0000 http://www.hindawi.com/journals/oci/2013/278143/ The mechanisms of synergistic biological effects observed in the simultaneous use of aromatic heterocyclic compounds in combination are reviewed, and the specific biological role of heteroassociation of aromatic molecules is discussed. Maxim P. Evstigneev Copyright © 2013 Maxim P. Evstigneev. All rights reserved. Thu, 03 Jan 2013 11:19:43 +0000 http://www.hindawi.com/journals/oci/2013/502343/ A new synthesis of hydroxytriarylmethane derived from the reaction of 2-sulfobenzoic anhydride and phenols in the presence of heteropolyacids as green, reusable, and efficient catalyst (using catalytic amount) under ultrasonic irradiation is reported in this paper. Hooshang Hamidian Copyright © 2013 Hooshang Hamidian. All rights reserved. Mon, 31 Dec 2012 12:52:48 +0000 http://www.hindawi.com/journals/oci/2012/279097/ 4,4′-(1,3-Phenylenebis(oxy))dianiline 1 is an aromatic diamine compound and has been very less utilized in the organic synthesis. Different diimines and diamides were synthesized by reacting compound 1 with aromatic and heterocyclic compounds having different functionalities. These longer electron rich spacer molecules were synthesized to utilize them in the near future in making macrocycles of different sizes and functionalities. A hydrazide was also prepared from a diamide spacer molecule containing ester group. A diamide prepared containing nibrobenzene moiety was further reduced to amine to obtain longer spacer diamine molecule than the starting molecule 1. Said Nadeem, Muhammad R. Shah, Kiramat Shah, Akhtar Mohammad, and Burhan Khan Copyright © 2012 Said Nadeem et al. All rights reserved. Sun, 23 Dec 2012 17:52:06 +0000 http://www.hindawi.com/journals/oci/2012/456097/ A rapid, efficient, and solvent-free methodology for synthesis of exocyclic α,β-unsaturated ketones of the categories E-3-arylidene-4-chromanones, E-2-arylidene-1-tetralones, E-2-arylidene-1-indanones, E-3-cinnamylidene-4-chromanones, E-2-cinnamylidene-1-tetralones, E-2-cinnamylidene-1-indanones, α,α′-(E,E)-bis(arylidene)-cycloalkanones, and α,α′-(E,E)-bis(cinnamylidene)-cycloalkanones has been developed through cross-aldol condensation of the constituent cyclic ketones and aldehydes by microwave irradiation over anhydrous potassium carbonate. However, for condensation of 1-thio-4-chromanones with aromatic aldehydes by this method, the initially formed exocyclic α,β-unsaturated ketone has been found to undergo isomerization yielding 3-(arylmethyl)thiochromones. Rina Mondal, Tapas K. Mandal, and Asok K. Mallik Copyright © 2012 Rina Mondal et al. All rights reserved. Thu, 13 Dec 2012 10:10:29 +0000 http://www.hindawi.com/journals/oci/2012/647386/ Environmentally benign mortar-pestle-induced practical methods have been developed for the acylation and O-alkylation of aromatic and heteroaromatic compounds under solventfree micellar conditions, which were found to efficiently afford moderate to excellent yields of products. Kancharla Rajendar Reddy, Kamatala Chinna Rajanna, Kusampally Uppalaiah, Mukka Satish Kumar, and Marri Venkateshwarlu Copyright © 2012 Kancharla Rajendar Reddy et al. All rights reserved. Wed, 05 Dec 2012 15:50:48 +0000 http://www.hindawi.com/journals/oci/2012/153159/ A mild and efficient method has been reported for the preparation of Schiff base ligands through the condensation reaction of various aromatic aldehydes with substituted aromatic amines in the presence of CES (calcined eggshell) as a heterogeneous catalyst under solvent-free conditions. The advantages of this ecofriendly, economic method are simplicity of the reaction procedure, moderate to good product yields, and very short reaction times. Suresh Patil, S. D. Jadhav, and S. K. Shinde Copyright © 2012 Suresh Patil et al. All rights reserved. Wed, 05 Dec 2012 14:19:22 +0000 http://www.hindawi.com/journals/oci/2012/956584/ An efficient synthesis of 3-benzyl-substituted 7H-thiazolo[3,2-a]pyrimine-7-ones in acetonitrile is accomplished via Pd- and Cu-catalyzed reaction of 2-mercaptopropargylpyrimidone with various aryl iodides in the presence of triethylamine as the base. Mohammad Bakherad and Farzaneh Gholipoor Copyright © 2012 Mohammad Bakherad and Farzaneh Gholipoor. All rights reserved. Thu, 22 Nov 2012 10:12:43 +0000 http://www.hindawi.com/journals/oci/2012/810476/ Regioselective iodocyclization of a series of allylhydroxy naphthalene precursors involving N-iodosuccinimide and environment friendly green approach associated with surfactant-promoted molecular-iodine-mediated 5-exo-trig cyclization strategies has been explored. Pradipta Kumar Basu and Amrita Ghosh Copyright © 2012 Pradipta Kumar Basu and Amrita Ghosh. All rights reserved. Wed, 21 Nov 2012 11:05:43 +0000 http://www.hindawi.com/journals/oci/2012/498521/ A versatile and convenient synthesis of 2-substituted benzimidazoles, using o-nitroaniline as starting material with several aryl aldehydes, has been accomplished by using a small amount of a reluctant agent. The reaction was carried out under very mild conditions at room temperature. The yields obtained are very good in reasonably short reaction times. Hossein Naeimi and Nasrin Alishahi Copyright © 2012 Hossein Naeimi and Nasrin Alishahi. All rights reserved. Mon, 19 Nov 2012 09:47:00 +0000 http://www.hindawi.com/journals/oci/2012/289023/ Aromatic compounds (phenols), when treated with Vilsmeier Haack (V-H) reagent in the presence of transition metal ions such as Cu(II), Ni(II), Co(II), Cd(II), and Zn(II) under reflux conditions, afforded corresponding ortho-formyl derivatives in good yields. Under normal conditions the metal-ion-free V-H reactions are too sluggish and resulted in poor yields. This protocol provides highly regioselective formylation under a mild and efficient condition with simple workup. F. Aneesa, K. C. Rajanna, Y. Arun Kumar, and M. Arifuddin Copyright © 2012 F. Aneesa et al. All rights reserved. Tue, 13 Nov 2012 14:57:14 +0000 http://www.hindawi.com/journals/oci/2012/191584/ We investigate L-Tyrosine as an efficient catalyst for the Knoevenagel condensation of arylaldehydes with meldrum’s acid containing cyclic active methylene group in solvent-free condition under grindstone method at room temperature to produce substituted-5-benzylidene-2,2-dimethyl-[1,3]dioxane-4,6-diones 3(a–j). G. Thirupathi, M. Venkatanarayana, P. K. Dubey, and Y. Bharathi Kumari Copyright © 2012 G. Thirupathi et al. All rights reserved. Mon, 12 Nov 2012 17:39:13 +0000 http://www.hindawi.com/journals/oci/2012/208128/ Three benzaldehyde-functionalized ionic liquids were readily synthesized by quaternization of N-alkylimidazole with benzaldehyde-functionalized alkyl bromides under microwave irradiation in good yield. These aldehyde-functionalized ionic liquids could easily be oxidized in the presence of H2O2/KOH or be reduced by NaBH4 leading to the formation of the corresponding carboxyl-functionalized ionic liquids or benzylic alcohol-functionalized ionic liquids. In addition, the condensations of these functionalized ones with hydrazine hydrate and with aniline under reductive amination conditions were demonstrated. Qiang Huang and Baozhong Zheng Copyright © 2012 Qiang Huang and Baozhong Zheng. All rights reserved. Sun, 04 Nov 2012 09:33:38 +0000 http://www.hindawi.com/journals/oci/2012/515092/ A simple and efficient method for N-arylation of 1,2,4-triazole at room temperature was described by the use of predominant (111) facet CuO nanoparticles as a catalyst in ligand-free condition. The catalyst was recyclable, and a variety of substrates give N-arylation product in high yield with short period of reaction time. The wide scope of this catalyst led us to investigate transformations involving less-reactive nitrogen nucleophiles, such as imidazole and pyrazoles. We were pleased to find that various derivatives of azoles were effectively coupled with aryl iodide to afford the desired N-arylated product in excellent yield. Nikhil V. Suramwar, Sanjay R. Thakare, and Niraj T. Khaty Copyright © 2012 Nikhil V. Suramwar et al. All rights reserved. Sun, 04 Nov 2012 09:17:02 +0000 http://www.hindawi.com/journals/oci/2012/306162/ Various coumarin derivatives have been efficiently synthesized via barium dichloride-catalyzed Pechmann condensation reaction of various phenols and β-keto esters under solvent-free conditions. This novel and inexpensive method has advantages such as short reaction times, excellent product yields, and avoidance of organic solvents in agreement with green chemistry principles. Saeed Khodabakhshi Copyright © 2012 Saeed Khodabakhshi. All rights reserved. Sun, 04 Nov 2012 08:08:42 +0000 http://www.hindawi.com/journals/oci/2012/293945/ The synthesis of a number of novel 4,6-disubstituted tetrahydropyrimidinones is described. The synthetic route described is applied to the synthesis of two stereoisomers. The structure of one tetrahydropyrimidinone was determined by XRD and showed an interesting hydrogen-bonded ribbon in the direction of crystal growth. These pyrimidinones are members of a class of compounds with diverse bioactivity. An initial study of their activity versus HIV protease is included. David Frain, Fiona Kirby, Patrick McArdle, and Patrick O'Leary Copyright © 2012 David Frain et al. All rights reserved. Mon, 15 Oct 2012 14:00:59 +0000 http://www.hindawi.com/journals/oci/2012/343768/ Viscometry is a valid and practical approach for monitoring the degradation of polymers in solution. In this work, at constant power and pulse, the effects of different operating parameters such as time of irradiation, temperature, solution concentration, volume, solvent, and immersion depth of horn on the rate of degradation have been investigated in aqueous solution using laboratory scale operation. A method of viscometry was used to study the degradation behavior of aqueous dispersions of microgels. The experimental results show that the viscosity of polymer solution decreased with an increase in the ultrasonic irradiation time and approached a limiting value. The present work has enabled us to understand the role of the different operating parameters in deciding the extent of viscosity reduction in aqueous dispersions of microgels and also the controlling effects of them. Rajabali Ebrahimi, Giti Tarhande, and Saeed Rafiei Copyright © 2012 Rajabali Ebrahimi et al. All rights reserved. Mon, 15 Oct 2012 08:34:10 +0000 http://www.hindawi.com/journals/oci/2012/282137/ Prior investigations from this laboratory concerned with the preparation of new types of organic cations for a variety of biological and nonbiological applications have been extended to the preparation of cation-bearing ligands with nitrogen coordinating sites for use in complexation reactions with ruthenium cores. The syntheses of new cationic ligands as well as ruthenium complexes bearing them are reported here. The introduction of these new types of ligands is intended to provide to the complexes an enhanced ability to interact with DNA, and thereby to have the potential to be enhanced antitumor agents. Preliminary observations of their interactions with DNA are presented. Leslie Babukutty, Ethan Moskovic, Davina Wadler, Thomas Strekas, and Robert Engel Copyright © 2012 Leslie Babukutty et al. All rights reserved. Wed, 26 Sep 2012 13:52:10 +0000 http://www.hindawi.com/journals/oci/2012/375656/ [BPy]HSO4 was prepared and used as an efficient and recyclable catalyst for the one-pot three-component synthesis of α-aminophosphonates at room temperature under solvent-free conditions with good-to-excellent yields. The workup procedure is very simple, and the catalyst can be reused at least four times without any loss in catalytic activity. Zhongqiang Zhou, Yaru Pei, and Lamei Wu Copyright © 2012 Zhongqiang Zhou et al. All rights reserved. Sun, 16 Sep 2012 13:52:02 +0000 http://www.hindawi.com/journals/oci/2012/208948/ A convenient and microwave-promoted novel protocol for the syntheses of diverse kinds of substituted benzopyrans from the corresponding variety of substituted hydroxy acetophenones and keto compounds using benzyltrimethylammonium hydroxide (Triton-B) under solvent-free conditions has been developed. This protocol is mild and efficient than the other reported methods. Devdutt Chaturvedi, Amit K. Chaturvedi, Nisha Mishra, and Virendra Mishra Copyright © 2012 Devdutt Chaturvedi et al. All rights reserved. Sun, 02 Sep 2012 15:23:01 +0000 http://www.hindawi.com/journals/oci/2012/194784/ A simple and efficient synthesis of 5-arylidene-2,4-thiazolidinediones by the Knoevenagel condensation of aromatic aldehydes with 2,4-thiazolidinedione catalyzed by ethylenediamine diacetate under solvent-free conditions is described. The major advantages of this method are simple experimental and work-up procedures, solvent-free reaction conditions, small amount of catalyst, short reaction time, high yields, and utilization of an inexpensive and reusable catalyst. Yuliang Zhang and Zhongqiang Zhou Copyright © 2012 Yuliang Zhang and Zhongqiang Zhou. All rights reserved. Wed, 22 Aug 2012 14:50:00 +0000 http://www.hindawi.com/journals/oci/2012/475301/ Silica-supported magnesium hydrogen sulfate has been used as a recyclable catalyst for the synthesis of some linear and cyclic aromatic acetals under solvent-free conditions. This environmentally friendly method has advantages, such as high yield of products, simple work-up procedure, and avoidance of the organic solvents, which will contribute in serving as a green process greatly. Fariba Jafari and Saeed Khodabakhshi Copyright © 2012 Fariba Jafari and Saeed Khodabakhshi. All rights reserved. Mon, 13 Aug 2012 16:07:25 +0000 http://www.hindawi.com/journals/oci/2012/284947/ A series of tetrachloroquinazolin-2,4-dione derivatives were synthesized using appropriate synthetic route and characterized by IR, 1H NMR, MS, and elemental analysis. The synthesized compounds were evaluated for their preliminary in vitro antibacterial activity towards Salmonella typhi, Staphylococcus aureus, and Bacillus cereus. M. A. Hassan, A. M. M. Younes, M. M. Taha, and A. Abdel-Monsef Copyright © 2012 M. A. Hassan et al. All rights reserved. Fri, 20 Jul 2012 13:52:44 +0000 http://www.hindawi.com/journals/oci/2012/828032/ A solvent-free synthesis of five series of coumarin derivatives using microwave assistant is presented herein. The synthesized compounds are fully characterized by UV-VIS, FT-IR, and NMR spectroscopy. Redah I. Al-Bayati, Mahdi F. Radey, and Ahmed A. Al-Amiery Copyright © 2012 Redah I. Al-Bayati et al. All rights reserved. Fri, 13 Jul 2012 16:55:23 +0000 http://www.hindawi.com/journals/oci/2012/278741/ The compound 𝑁1-phenylhydrazine-1,2-bis(carbothioamide) was synthesised from phenylisothiocyanate reacting with thiosemicarbazide refluxing the mixture in ethanol. The new compound obtained was characterised by various spectral and elemental analyses. It was subjected to antibacterial, antioxidant and brine shrimp lethality bioassay. The compound showed brine shrimp lethality with LC50 value of 12.79 μg which was comparable to vincristine with LC50 value of 0.33 μg. The compound did not exhibit any antimicrobial activity against Gram +ve and Gram −ve organisms, as well as against the tested fungal strains. But very good free radical scavenging activity was observed at concentration range of 0.185–100 μg with IC50 values of 1.43 μg in comparison to reference standard butylated hydroxytoluene (BHT) with IC50 value 16.46 μg. G. M. Golzar Hossain, Md. Mainul Abedin, and Sitesh C. Bachar Copyright © 2012 G. M. Golzar Hossain et al. All rights reserved. Sun, 01 Jul 2012 15:11:43 +0000 http://www.hindawi.com/journals/oci/2012/206025/ Copper biogeochemistry is controlled by bonding to natural organic matter. The soluble forms of bonded copper can be more biologically active due to the higher migration in environmental systems and instability of some copper-humic complexes. In this work, the interactions of copper(II) ions with humic acids are studied by means of high-resolution ultrasound spectrometry. It was found that the stoichiometry of the formed complexes is strongly influenced by the organization of humic acid in solution and by the final pH value in equilibrium. Although the ratio between the added copper and humic acids in all used concentrations was constant and the initial pH value was neutral, we observed significant differences between the individual systems. The highest binding ability was determined for a humic content of 0.5 g·dm−3. More diluted and more concentrated systems were able to bind lower amounts of copper. The implemented method is very sensitive and can be utilized not only for monitoring copper binding but also as an indicator of conformational changes of humic acid in solutions with varying concentration. Martina Klučáková Copyright © 2012 Martina Klučáková. All rights reserved. Sun, 08 Apr 2012 08:46:09 +0000 http://www.hindawi.com/journals/oci/2012/819190/ The oscillatory modes of oxidative carbonylation reaction of two new substrates—2-methyl-3-butyn-2-ol and 2-propyn-1-ol in homogeneous system PdI2-KI-CO-O2-CH3OH are found. Borders of oscillatory areas are drawn, the basic products of reaction are identified, and probable processes routes are offered. Sergey Nikolaevich Gorodsky Copyright © 2012 Sergey Nikolaevich Gorodsky. All rights reserved.