ISRN Organic Chemistry The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Crystal Structure and Stereochemistry Study of 2-Substituted Benzoxazole Derivatives Tue, 13 May 2014 10:04:13 +0000 The structure of 2-[(4-chlorophenylazo) cyanomethyl] benzoxazole, C15H9ClN4O (I), has triclinic () symmetry. The structure displays hydrogen bonding. The structure of 2-[(arylidene) cyanomethyl] benzoxazoles, C17H10N2O3 (II), has triclinic () symmetry. The structure displays , hydrogen bonding. In (I), the chlorophenyl and benzoxazole groups adopt a trans configuration with respect to the central cyanomethyle hydrazone moiety. Compound (II) crystallized with two molecules in the asymmetric unit shows cisoid conformation between cyano group and benzoxazole nitrogen, contrary to (I). In (II) the benzodioxole has an envelope conformation (the C17 atom is the flap atom). The molecular geometry obtained using molecular mechanics (MM) calculations has been discussed along with the results of single crystal analysis. Ahmed F. Mabied, Elsayed M. Shalaby, Hamdia A. Zayed, Esmat El-Kholy, Ibrahim S. A. Farag, and Naima A. Ahmed Copyright © 2014 Ahmed F. Mabied et al. All rights reserved. Synthesis, Spectral Analysis, In Vitro Microbiological Evaluation, and Molecular Docking Studies of Some Novel 1-(1-Aryl-1H-tetrazol-5-yl)-2-(piperidin-1-yl)ethanone Derivatives Tue, 06 May 2014 13:04:41 +0000 A new series of novel heterocyclic compounds containing both tetrazoles and piperidine nuclei together, namely, 1-(1-aryl-1H-tetrazol-5-yl)-2-(piperidin-1-yl)ethanone (22–28), were synthesized by the treatment of the respective 2-chloro-1-(1-aryl-1H-tetrazol-5-yl)ethanone (15–21) with piperidine in acetonitrile for 6 h. A series of novel tetrazole substituted piperidine derivatives were synthesized and evaluated for their antimicrobial activity using serial dilution method. The structures of the synthesized compounds were characterized by IR, 1H NMR, 13C NMR, mass spectral data, and elemental analysis. Evaluation of antimicrobial activity shows that several compounds exhibit good activity when compared with the reference drug candidates and thus could be promising new lead molecules. Thangasamy Elavarasan, Durairaj Peter Bhakiaraj, and Mannathusamy Gopalakrishnan Copyright © 2014 Thangasamy Elavarasan et al. All rights reserved. A Facile Stereoselective Total Synthesis of (R)-Rugulactone Sun, 30 Mar 2014 00:00:00 +0000 An efficient and novel synthesis of (R)-rugulactone has been achieved employing Sharpless asymmetric epoxidation of allyl alcohols followed by selective hydride reduction of epoxy alcohols and olefin cross metathesis reactions. B. Narasimha Reddy and R. P. Singh Copyright © 2014 B. Narasimha Reddy and R. P. Singh. All rights reserved. Asymmetric Organocatalysis at the Service of Medicinal Chemistry Tue, 11 Mar 2014 14:47:17 +0000 The application of the most representative and up-to-date examples of homogeneous asymmetric organocatalysis to the synthesis of molecules of interest in medicinal chemistry is reported. The use of different types of organocatalysts operative via noncovalent and covalent interactions is critically reviewed and the possibility of running some of these reactions on large or industrial scale is described. A comparison between the organo- and metal-catalysed methodologies is offered in several cases, thus highlighting the merits and drawbacks of these two complementary approaches to the obtainment of very popular on market drugs or of related key scaffolds. Alfredo Ricci Copyright © 2014 Alfredo Ricci. All rights reserved. Efficient Electrochemical N-Alkylation of N-Boc-Protected 4-Aminopyridines: Towards New Biologically Active Compounds Wed, 05 Mar 2014 13:24:43 +0000 The use of electrogenerated acetonitrile anion allows the alkylation of N-Boc-4-aminopyridine in very high yields, under mild conditions and without by-products. The high reactivity of this base is due to its large tetraethylammonium counterion, which leaves the acetonitrile anion “naked.” The deprotection of the obtained compounds led to high yields in N-alkylated 4-aminopyridines. Nonsymmetrically dialkylated 4-aminopyridines were obtained by subsequent reaction of monoalkylated ones with t-BuOK and alkyl halides, while symmetrically dialkylated 4-aminopyridines were obtained by direct reaction of 4-aminopyridine with an excess of t-BuOK and alkyl halides. Some mono- and dialkyl-4-aminopyridines were selected to evaluate antifungal and antiprotozoal activity; the dialkylated 4-aminopyridines 3ac, 3ae and 3ff showed antifungal towards Cryptococcus neoformans; whereas 3cc, 3ee and 3ff showed antiprotozoal activity towards Leishmania infantum and Plasmodium falciparum. Marta Feroci, Isabella Chiarotto, Gianpiero Forte, Giovanna Simonetti, Felicia Diodata D'Auria, Louis Maes, Daniela De Vita, Luigi Scipione, Laura Friggeri, Roberto Di Santo, and Silvano Tortorella Copyright © 2014 Marta Feroci et al. All rights reserved. Antimicrobial and Dyeing Properties of Reactive Dyes with Thiazolidinon-4-one Nucleus Tue, 04 Mar 2014 07:48:24 +0000 Four imines, the condensation products of 2,4-dioxo-4-phenylbutanal with four primary amines, were condensed with mercapto acetic acid to obtain thiazolidinon-4-ones which on subsequent condensation with vanillin and isatin separately yielded eight thiazolidin-4-one derivatives. The chemical structures of the synthesized compounds were elucidated by elemental analysis, molecular weight determination, IR and 1H and 13C NMR spectral measurements. Antibacterial and antifungal properties were studied in vitro against two bacteria and two fungi. The dyeing potential of synthesized reactive dyes was investigated with regard to silk, wool, cotton, and polyester fabrics under hot and cold dyeing conditions. Hailemichael Ayalew, Gebremedihin Reda, Tsegaye Gashaw, Neelaiah Babu, and Raj Kumar Upadhyay Copyright © 2014 Hailemichael Ayalew et al. All rights reserved. Substrate Directed Regioselective Monobromination of Aralkyl Ketones Using N-Bromosuccinimide Catalysed by Active Aluminium Oxide: α-Bromination versus Ring Bromination Tue, 04 Mar 2014 07:42:49 +0000 Bromination of aralkyl ketones using N-bromosuccinimide in presence of active Al2O3 provided either α-monobrominated products in methanol at reflux or mononuclear brominated products in acetonitrile at reflux temperature with excellent isolated yields depending on the nature of substrate employed. The α-bromination was an exclusive process when aralkyl ketones containing moderate activating/deactivating groups were subjected to bromination under acidic Al2O3 conditions in methanol at reflux while nuclear functionalization was predominant when aralkyl ketones containing high activating groups were utilized for bromination in presence of neutral Al2O3 conditions in acetonitrile at reflux temperature. In addition, easy isolation of products, use of inexpensive catalyst, short reaction time (10–20 min), and safe operational practice are the major benefits in the present protocol. Reddy Bodireddy Mohan, G. Trivikram Reddy, and N. C. Gangi Reddy Copyright © 2014 Reddy Bodireddy Mohan et al. All rights reserved. Synthesis and Biological Activities of 4-Aminoantipyrine Derivatives Derived from Betti-Type Reaction Tue, 04 Mar 2014 06:40:23 +0000 The present work deals with the synthesis and evaluation of biological activities of 4-aminoantipyrine derivatives derived from a three-component Betti reaction. The synthesis was initiated by the condensation of aromatic aldehyde, 4-aminoantipyrine, and 8-hydroxyquinoline in presence of fluorite as catalyst in a simple one-step protocol. The reactions were stirred at room temperature for 10–15 min achieving 92–95% yield. The structures of synthesized derivatives were established on the basis of spectroscopic and elemental analysis. All derivatives 4(a–h) were screened in vivo and in vitro for anti-inflammatory and anthelmintic activity against a reference drug, Diclofenac and Albendazole, respectively. The screening results show that compounds 4c, 4d, 4f, and 4h were found to possess potential anti-inflammatory activity while compounds 4a, 4b, 4e, and 4g are potent anthelmintic agents when compared with reference drugs, respectively. The bioactivity of these derivatives has also been evaluated with respect to Lipinski’s rule of five using molinspiration cheminformatics software. Ipsita Mohanram and Jyotsna Meshram Copyright © 2014 Ipsita Mohanram and Jyotsna Meshram. All rights reserved. Goniomitine: An Overview on the Chemistry of This Indole Alkaloid Mon, 23 Dec 2013 16:09:41 +0000 This paper reports an overview on the chemistry of the indole alkaloid goniomitine focusing, mainly, on the methods of synthesis related to this natural product and analogs. José C. F. Alves Copyright © 2013 José C. F. Alves. All rights reserved. An Efficient Synthesis of Bis-indolylindane-1,3-diones, Indan-1,3-diones, and Indene-1,3(2H)-denies Using [Hbim]BF4 Ionic Medium Mon, 16 Dec 2013 15:43:49 +0000 We prepared a brand new molecule in one step for the synthesis of bis-indolylindane-1,3-dione and indan-1,3-diones from the reaction of ninhydrin and 3 substituted/unsubstituted indoles using [Hbim]BF4 ionic liquid in excellent yields. The method was also used for the synthesis of novel indene-1,3(2H)-denies derivatives. Mohammad Reza Poor Heravi Copyright © 2013 Mohammad Reza Poor Heravi. All rights reserved. Silica-ZnCl2: An Efficient Catalyst for the Synthesis of 4-Methylcoumarins Mon, 16 Dec 2013 09:46:02 +0000 Silica-ZnCl2 has been found to be an efficient and eco-friendly catalyst for the synthesis of substituted 4-methylcoumarins from ethyl acetoacetate and substituted phenols under “neat” conditions in an oil bath at 80°C. The experimental procedure is simple, includes shorter reaction times (15–65 min), compatible with sensitive functional groups, and results in excellent yield of the products. Bandita Datta and Mohamed Afzal Pasha Copyright © 2013 Bandita Datta and Mohamed Afzal Pasha. All rights reserved. ZSM-5-SO3H: An Efficient Catalyst for Acylation of Sulfonamides Amines, Alcohols, and Phenols under Solvent-Free Conditions Sun, 08 Dec 2013 11:16:11 +0000 Sulfonamides amines, alcohols, and phenols were efficiently acylated with carboxylic acid anhydrides and chlorides using ZSM-5-SO3H as catalyst under mild and solvent-free conditions. Also, direct esterification of alcohols with carboxylic acids occurred readily in the presence of this catalyst. Different types of amides and esters were obtained in moderate to high yields and purity after a simple workup. No chromatographic separation is needed for isolation of the acylated product. The catalyst was recovered and reused for up to four times without a noticeable decrease in catalytic activity. Ahmad Reza Massah, Roozbeh Javad Kalbasi, Mahdiehsadat Khalifesoltani, and Fariba Moshtagh Kordesofla Copyright © 2013 Ahmad Reza Massah et al. All rights reserved. New L-Serine Derivative Ligands as Cocatalysts for Diels-Alder Reaction Thu, 05 Dec 2013 14:25:59 +0000 New L-serine derivative ligands were prepared and tested as cocatalyst in the Diels-Alder reactions between cyclopentadiene (CPD) and methyl acrylate, in the presence of several Lewis acids. The catalytic potential of the in situ formed complexes was evaluated based on the reaction yield. Bidentate serine ligands showed good ability to coordinate medium strength Lewis acids, thus boosting their catalytic activity. The synthesis of the L-serine ligands proved to be highly efficient and straightforward. Carlos A. D. Sousa, José E. Rodríguez-Borges, and Cristina Freire Copyright © 2013 Carlos A. D. Sousa et al. All rights reserved. Solvent-Free Green and Efficient One-Pot Synthesis of Dihydropyrano[3,2-c]chromene Derivatives Thu, 24 Oct 2013 08:33:33 +0000 A rapid, clean, and highly efficient method for synthesis of dihydropyrano[3,2-c]chromene derivatives by one-pot, three-component condensation of aromatic aldehydes, malononitrile, and 4-hydroxycoumarin using DABCO as catalyst in solvent-free neat conditions is described. The present method has the advantages of mild reaction conditions, short reaction times, easy isolation of products, and excellent yields. Shubha Jain, Deepika Rajguru, Balwant S. Keshwal, and Aman D. Acharya Copyright © 2013 Shubha Jain et al. All rights reserved. Synthesis and Biological Evaluation of Some [1,2,4]Triazolo[4,3-a]quinoxaline Derivatives as Novel Anticonvulsant Agents Thu, 12 Sep 2013 09:31:17 +0000 2-([1,2,4]Triazolo[4,3-a]quinoxalin-4-ylthio)acetic acid hydrazide (10) was used as a precursor for the syntheses of novel quinoxaline derivatives with potential anticonvulsant properties. The newly synthesized compounds have been characterized by IR, 1H NMR, and mass spectral data followed by elemental analysis. The anticonvulsant evaluation was carried out for eleven of the synthesized compounds using metrazol induced convulsions model and phenobarbitone sodium as a standard. Among this set of tested compounds, two of them (14, and 15b) showed the best anticonvulsant activities. Mohamed Alswah, Adel Ghiaty, Ahmed El-Morsy, and Kamal El-Gamal Copyright © 2013 Mohamed Alswah et al. All rights reserved. Chemical Modification of Polysaccharides Tue, 10 Sep 2013 11:38:38 +0000 This review covers methods for modifying the structures of polysaccharides. The introduction of hydrophobic, acidic, basic, or other functionality into polysaccharide structures can alter the properties of materials based on these substances. The development of chemical methods to achieve this aim is an ongoing area of research that is expected to become more important as the emphasis on using renewable starting materials and sustainable processes increases in the future. The methods covered in this review include ester and ether formation using saccharide oxygen nucleophiles, including enzymatic reactions and aspects of regioselectivity; the introduction of heteroatomic nucleophiles into polysaccharide chains; the oxidation of polysaccharides, including oxidative glycol cleavage, chemical oxidation of primary alcohols to carboxylic acids, and enzymatic oxidation of primary alcohols to aldehydes; reactions of uronic-acid-based polysaccharides; nucleophilic reactions of the amines of chitosan; and the formation of unsaturated polysaccharide derivatives. Ian Cumpstey Copyright © 2013 Ian Cumpstey. All rights reserved. An Eco-Friendly Improved Protocol for the Synthesis of Bis(3-indolyl)methanes Using Poly(4-vinylpyridinium)hydrogen Sulfate as Efficient, Heterogeneous, and Recyclable Solid Acid Catalyst Mon, 02 Sep 2013 10:14:42 +0000 Highly efficient and eco-friendly protocol for the synthesis of bis(3-indolyl)methanes by the electrophilic substitution reaction of indole with aldehydes catalyzed by poly(4-vinylpyridinium)hydrogen sulfate was described. Excellent yields, shorter reaction times, simple work-up procedure, avoiding hazardous organic solvents, and reusability of the catalyst are the most obvious advantages of this method. Janardhan Banothu, Rajitha Gali, Ravibabu Velpula, Rajitha Bavantula, and Peter A. Crooks Copyright © 2013 Janardhan Banothu et al. All rights reserved. Design, Synthesis, and In Vitro Antimicrobial Evaluation of Fused Pyrano[3,2-e]tetrazolo[1,5-c]pyrimidines and Diazepines Wed, 21 Aug 2013 10:00:04 +0000 A series of novel pyranochromene-containing tetrazoles fused with pyrimidinethiones, pyrimidines, and diazepines 3a–f, 4a–f, and 5a–f were synthesized by condensation of the corresponding tetrazoles 2a–f with carbon disulfide, benzaldehyde, and 4-methoxy phenacyl bromide, respectively. The compound 2a–f was obtained by reaction of pyrano[3,2-c]chromenes 1a–f with sodium azide. The structures of the newly synthesized compounds 2a–f to 5a–f were established on the basis of their elemental analyses, IR, 1H NMR, 13C NMR, and mass spectral data. All of the title compounds were subjected to in vitro antibacterial testing against four pathogenic strains and antifungal screening against two fungi. Preliminary results indicate that some of them exhibited promising activities and that they deserve more consideration as potential antimicrobials. Sankari Kanakaraju, P. Sagar Vijay Kumar, Bethanamudi Prasanna, and G. V. P. Chandramouli Copyright © 2013 Sankari Kanakaraju et al. All rights reserved. Synthesis and Antioxidant Activity of 2-Amino-5-methylthiazol Derivatives Containing 1,3,4-Oxadiazole-2-thiol Moiety Mon, 19 Aug 2013 13:37:06 +0000 A series of new 5-(2-amino-5-methylthiazol-4-yl)-1,3,4-oxadiazole-2-thiol derivatives 6(a–j) were designed and synthesized with various substituted aldehydes. The chemical structures were confirmed by elemental analyses, FT-IR, 1H NMR, and mass spectral studies. The antioxidant activity of the synthesized compounds was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, nitric oxide, and superoxide radical scavenging assay methods. Compounds 6a, 6e, and 6c showed significant radical scavenging potential due to the presence of electron donating substituent on substituted aldehydes. Kikkeri N. Mohana and Chikkur B. Pradeep Kumar Copyright © 2013 Kikkeri N. Mohana and Chikkur B. Pradeep Kumar. All rights reserved. Three Component Reaction: An Efficient Synthesis and Reactions of 3,4-Dihydropyrimidin-2(1H)-Ones and Thiones Using New Natural Catalyst Sun, 18 Aug 2013 08:53:33 +0000 Synthesis of 3,4-dihydropyrimidin-2(1H)-one and 3,4-dihydropyrimidin-2(1H)-thione derivatives from aldehydes, 1,3-dicarbonyl derivatives and urea or thiourea using granite and quartz as new, natural and reusable catalysts. Some of the 3,4-dihydropyrimidin-2(1H)-thione derivatives were used to prepare new heterocyclic compounds. The antimicrobial activity of selected examples of the synthesized compounds was tested and showed moderate activity. A. M. Elmaghraby, I. A. Mousa, A. A. Harb, and M. Y. Mahgoub Copyright © 2013 A. M. Elmaghraby et al. All rights reserved. Nanorod-Shaped Basic Catalyzed N,N-Diformylation of Bisuracil Derivatives: A Greener “NOSE” Approach Wed, 26 Jun 2013 13:34:53 +0000 A feasible “NOSE” (nanoparticles-catalyzed organic synthesis enhancement) protocol has been developed for N,N-diformylation of bisuracil derivatives using nano-Al2O3 rods as an efficient, inexpensive, and recyclable catalyst under solvent-free reaction condition at 40°C. The catalyst was reused up to the 4th cycle without affecting the rate and yield of the N,N-diformylation products appreciably. Vijay K. Das and Ashim J. Thakur Copyright © 2013 Vijay K. Das and Ashim J. Thakur. All rights reserved. The Potential of Isotopomers as a Test for the Vibrational Theory of Olfactory Sense Recognition Sun, 26 May 2013 10:44:07 +0000 The continuing debate over the basis of odorant recognition with respect to the molecular shape (“lock and key”) theory versus the vibrational theory could potentially be resolved by the testing of 13C-labeled odorants. The application of 13C isotopomers is discussed herein by means of DFT-calculated IR vibrations and Gibbs’ free energies (Δ) for acetophenone and octan-1-ol, two odorants for which the 2D (deuterium) isotopomers have previously been shown to be discernible from their respective 1H (normal) counterparts by Drosophila melanogaster. Karel D. Klika Copyright © 2013 Karel D. Klika. All rights reserved. A Simple, Efficient Synthesis of 2-Aryl Benzimidazoles Using Silica Supported Periodic Acid Catalyst and Evaluation of Anticancer Activity Wed, 24 Apr 2013 14:16:04 +0000 A new, efficient method for the synthesis of 2-aryl substituted benzimidazole by using silica supported periodic acid (H5IO6-SiO2) as a catalyst has been developed. The salient feature of the present method includes mild reaction condition, short reaction time, high yield and easy workup procedure. The synthesized benzimidazoles exhibited potent anticancer activity against MCF7 and HL60 cell lines. Vyankat A. Sontakke, Sougata Ghosh, Pravin P. Lawande, Balu A. Chopade, and Vaishali S. Shinde Copyright © 2013 Vyankat A. Sontakke et al. All rights reserved. Synthesis, Characterization, and BSA Binding Studies of Some New Benzamides Related to Schiff Base Sun, 07 Apr 2013 15:42:19 +0000 Condensation of amine 1 with aldehyde 2 gives Schiff base, N-(4-((benzofuran-2-ylmethylene) amino)phenyl)acetamide 3. Schiff base on N-acylation with different substituted acid chlorides in the presence of triethylamine gives the corresponding benzamides, N-acetyl-N-(4-((benzofuran-2-ylmethylene)amino)phenyl)substitutedbenzamide (NABP) 5a–j. The structures of newly synthesized compounds were characterized by elemental analysis, 1H NMR, 13C NMR FT-IR, and mass spectral studies. Compounds 3 and 5a–j have been screened for their antimicrobial activity using the disc diffusion and minimum inhibitory concentration (MIC) method against the selected bacterial and fungal strain. Compounds 5a, 5e, 5g, and 5h were found to be more active against all tested strains. The antioxidant properties were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging methods. Compounds 5i and 5j showed predominant antioxidant activities among the synthesized analogues. The interaction between NABP and bovine serum albumin (BSA) was investigated using fluorescence and ultraviolet spectroscopic techniques at 298 K under imitated physiological conditions. The results revealed that NABP caused the fluorescence quenching of BSA through a static quenching procedure. The binding constants and the number of binding sites were calculated. The binding distance between the donor (BSA) and acceptor (NABP) was determined based on Forster’s theory. M. K. Prashanth, M. Madaiah, H. D. Revanasiddappa, and K. N. Amruthesh Copyright © 2013 M. K. Prashanth et al. All rights reserved. Noncovalent Functionalization of Graphene in Suspension Thu, 28 Mar 2013 17:12:07 +0000 Suspensions of graphene, prepared from graphite foil by sonochemical exfoliation, have been treated with new nonpolar pyrenebutyric amides. The assemblies, in suspension and after deposition on solid supports, were characterized by NMR, absorption, and fluorescence spectroscopy and by transmission electron microscopy, where the well-defined shape and size of an appended [60]fulleropyrrolidine unit facilitates TEM detection of the nonstationary molecules. The accumulated evidence, also including direct comparisons of carbon nanotubes treated with pyrene amides under the same conditions, proves the successful noncovalent functionalization of graphene suspended in non-polar solvent with non-polar pyrene derivatives. Wenzhi Yang, Sultan Akhtar, Klaus Leifer, and Helena Grennberg Copyright © 2013 Wenzhi Yang et al. All rights reserved. DABCO Catalyzed Synthesis of Xanthene Derivatives in Aqueous Media Mon, 18 Mar 2013 11:58:47 +0000 The reaction of 5,5-dimethylcyclohexane-1,3-dione with various heteroarylaldehydes afforded the corresponding heteroaryl substituted xanthene derivatives 1(a–f). The reaction proceeds via the initial Knoevenagel, subsequent Michael, and final heterocyclization reactions using 1,4-diazabicyclo[2.2.2]octane (DABCO) as a catalyst in aqueous media. The synthesized heteroaryl substituted xanthenes 1(a–f) reacted with malononitrile to obtain different alkylidenes 2(a–f). Short reaction time, environmentally friendly procedure, avoiding of cumbersome apparatus, and excellent yields are the main advantages of this procedure which makes it more economic than the other conventional methods. Pradeep Paliwal, Srinivasa Rao Jetti, Anjna Bhatewara, Tanuja Kadre, and Shubha Jain Copyright © 2013 Pradeep Paliwal et al. All rights reserved. Synthesis and In Vitro Evaluation of Novel Acyclic and Cyclic Nucleoside Analogs with a Thiadiazole Ring Tue, 05 Mar 2013 10:37:49 +0000 The synthesis of six thiadiazole nucleoside analogs is reported: 5-diacetylamino-1,2,4-thiadiazol-3-one (1), 5-amino-2- (tetrahydrofuran-2-yl)-1,2,4-thiadiazol-3-one (2), 5-amino-3-[(2′-hydroxyethoxy)methyl]-1,3,4-thiadiazol-2-one (3), 5-amino-3-(4′-hydroxy-2′-hydroxymethyl-butyl)-1,3,4-thiadiazole-2-thione (4), (R)-5-amino-3-(2′,3′-dihydroxypropyl)-1,3,4-thiadiazole-2-thione (5), and (S)-5-amino-3-(2′,3′-dihydroxypropyl)-1,3,4-thiadiazole-2-thione (6). The synthesis, characterization, and properties of these new synthesized thiadiazole derivatives are discussed. A dimerization of 5-amino-3H-1,3,4-thiadiazole-2-thione (14) by sodium nitrite resulting in di-(5-amino-1,3,4-thiadiazol-2-yl) disulfide (19) is also reported. The preliminary in vitro evaluation of these newly synthesized compounds is discussed. Yuxiang Zhao, Peter J. McCarthy, and Cyril Párkányi Copyright © 2013 Yuxiang Zhao et al. All rights reserved. Interaction of 5′-Guanosine Monophosphate with Organotin(IV) Moieties: Synthesis, Structural Characterization, and Anti-Inflammatory Activity Sun, 09 Dec 2012 11:12:26 +0000 Reaction(s) of -guanosine monophosphate (GMP) with di- and triorganotin(IV) chloride(s) led to formation of organotin(IV) derivatives of general formulae, [R2Sn(-GMP)·H2O]n and [(R′3Sn)2(-GMP)·H2O]n, where R = Me, n-Bu, and Ph; R′ = Me, i-Pr, n-Bu, and Ph; (-GMP)2− = -guanosine monophosphate. An attempt has been made to prove the structures of the resulting derivatives on the basis of FT-IR, multinuclear 1H, 13C, and 119Sn NMR and 119Sn Mössbauer spectroscopic studies. These investigations suggest that both di- and triorganotin(IV)--guanosine monophosphates are polymeric in which (-GMP)2− is bonded through phosphate group resulting in a distorted trigonal bipyramidal geometry around tin. The ribose conformation in all of the derivatives is C3′-endo, except diphenyltin(IV) and tri-i-propyltin(IV) derivatives where it is C2′-endo. All of the studied derivatives exhibited mild-to-moderate anti-inflammatory activity (~15.64–20.63% inhibition) at 40 mg kg−1 dose and LD50 values > 400 mg kg−1 in albino rats. Mala Nath, Hitendra Singh, George Eng, and Xueqing Song Copyright © 2012 Mala Nath et al. All rights reserved. Facile Iodine-Catalyzed Michael Addition of Indoles to ,-Bis(arylmethylene)cyclopentanones: An Efficient Synthesis of E-2-(3-Indolylphenylmethyl)-5-phenylmethylenecyclopentanones Wed, 28 Nov 2012 13:15:07 +0000 Iodine-catalyzed reaction of indoles with ,-bis(arylmethylene)cyclopentanones afforded one diastereomer of the corresponding Michael adducts, namely, E-2-(3-indolylphenylmethyl)-5-phenylmethylenecyclopentanones, in a good yield. The products form a new group of indole derivatives. Rammohan Pal, Arpita Das Gupta, and Asok K. Mallik Copyright © 2012 Rammohan Pal et al. All rights reserved. An Efficient One-Pot Green Protocol for the Synthesis of 5-Unsubstituted 3,4-Dihydropyrimidin-2(1H)-Ones Using Recyclable Amberlyst 15 DRY as a Heterogeneous Catalyst via Three-Component Biginelli-Like Reaction Thu, 22 Nov 2012 14:42:00 +0000 An environmentally benign green protocol for the synthesis of 5-unsubstituted 3,4-dihydropyrimidin-2(1H)-ones using Amberlyst 15 DRY as a recyclable catalyst has been developed. The use of resinous, nontoxic, thermally stable, and inexpensive Amberlyst 15 DRY, as a recyclable heterogeneous catalyst, makes the process simple with negligible chemical waste. Among the various solid acid catalysts Amberlyst 15 DRY was found to be the most efficient catalyst with regard to reaction time, yield, and ease of work-up procedure. Srinivasa Rao Jetti, Divya Verma, and Shubha Jain Copyright © 2012 Srinivasa Rao Jetti et al. All rights reserved.