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Two hydrogen-bonded 3-mer arylamide foldamers 1 and 2, which bear two pyridine or iodobenzene subunits at the ends, have been designed and prepared. Compound 1 co-assembles with 1,4-diiodotetrafluorobenzene (3) to form 2 + 2 macrocycles through four (py)N…I halogen bonds, whereas compound 2 dimerizes into a macrocycle through two C=O…I hydrogen bonds. Macrocycles formed by 1 and 3 stack to produce a supramolecular tube, with two neighboring macrocycles encapsulating one molecule of 3 through two C=O…I halogen bonds. Through such a cross-layer connection, formally the two molecules also give rise to a new halogen-bonded supramolecular helix, and further stack alternately to afford a double helix. In contrast, the mixture of 1 and fumaric acid (5) did not produce a similar encapsulation-derived helix, even though they also formed a halogen-bonded 2 + 2 supramolecular macrocycle. [ABSTRACT FROM AUTHOR]

Halogen bonding has been used to glue together hydrogen‐bonded short arylamide foldamers to achieve new supramolecular double and quadruple helices in the solid state. Three compounds, which bear a pyridine at one end and either a CF2I or fluorinated iodobenzene group at the other end, engage in head‐to‐tail N⋅⋅⋅I halogen bonds to form one‐component supramolecular P and M helices, which stack to afford supramolecular double‐stranded helices. One of the double helices can dimerize to form a G‐quadruplex‐like supramolecular quadruple helix. Another symmetric compound, which bears a pyridine at each end, binds to ICF2CF2I through N⋅⋅⋅I halogen bonds to form two‐component supramolecular P and M helices, with one turn consisting of four (2+2) molecules. Half of the pyridine‐bearing molecules in two P helices and two M helices stack alternatingly to form another supramolecular quadruple helix. Another half of the pyridine‐bearing molecules in such quadruple helices stack alternatingly with counterparts from neighboring quadruple helices, leading to unique quadruple helical arrays in two‐dimensional space. Glued in place: Halogen bonds glue together short hydrogen‐bonded arylamide molecules to form either one‐ or two‐component helices. The helices stack to produce supramolecular quadruple and double helical structures. [ABSTRACT FROM AUTHOR]

Halogen bonding has been used to glue together hydrogen‐bonded short arylamide foldamers to achieve new supramolecular double and quadruple helices in the solid state. Three compounds, which bear a pyridine at one end and either a CF2I or fluorinated iodobenzene group at the other end, engage in head‐to‐tail N⋅⋅⋅I halogen bonds to form one‐component supramolecular P and M helices, which stack to afford supramolecular double‐stranded helices. One of the double helices can dimerize to form a G‐quadruplex‐like supramolecular quadruple helix. Another symmetric compound, which bears a pyridine at each end, binds to ICF2CF2I through N⋅⋅⋅I halogen bonds to form two‐component supramolecular P and M helices, with one turn consisting of four (2+2) molecules. Half of the pyridine‐bearing molecules in two P helices and two M helices stack alternatingly to form another supramolecular quadruple helix. Another half of the pyridine‐bearing molecules in such quadruple helices stack alternatingly with counterparts from neighboring quadruple helices, leading to unique quadruple helical arrays in two‐dimensional space. [ABSTRACT FROM AUTHOR]

A practical chemoenzymatic method for the synthesis of 9-hydroxynonanoic acid and 1,9-nonanedioic acid (i.e., azelaic acid) from oleic acid [(9 Z)-octadec-9-enoic acid] was investigated. Biotransformation of oleic acid into 9-(nonanoyloxy)nonanoic acid via 10-hydroxyoctadecanoic acid and 10-keto-octadecanoic acid was driven by a C-9 double bond hydratase from Stenotrophomonas maltophilia, an alcohol dehydrogenase from Micrococcus luteus, and a Baeyer-Villiger monooxygenase (BVMO) from Pseudomonas putida KT2440, which was expressed in recombinant Escherichia coli. After production of the ester (i.e., the BVMO reaction product), the compound was chemically hydrolyzed to n-nonanoic acid and 9-hydroxynonanoic acid because n-nonanoic acid is toxic to E. coli. The ester was also converted into 9-hydroxynonanoic acid and the n-nonanoic acid methyl ester, which can be oxygenated into the 9-hydroxynonanoic acid methyl ester by the AlkBGT from P. putida GPo1. Finally, 9-hydroxynonanoic acid was chemically oxidized to azelaic acid with a high yield under fairly mild reaction conditions. For example, whole-cell biotransformation at a high cell density (i.e., 10 g dry cells/L) allowed the final ester product concentration and volumetric productivity to reach 25 mM and 2.8 mM h−1, respectively. The overall molar yield of azelaic acid from oleic acid was 58%, based on the biotransformation and chemical transformation conversion yields of 84% and 68%, respectively. [ABSTRACT FROM AUTHOR]

A series of new 3,6-diphenylimidazo[2,1- b ]thiazole derivatives ( 4a – l ) are synthesized and evaluated for their anticancer activity. Some of the synthesized compounds have shown potent anti-proliferative activity against HeLa, MDA-MB-231, A549 and THP1 human cancer cell lines. Among the active compounds, 3-(3-trifluoromethylphenyl)-6-phenylimidazo[2,1- b ]thiazole ( 4j ) has caused significant cytotoxicity in HeLa cells, with IC 50 as low as 6.5 μM. Compound 4j has induced caspase-3 and caspase-8 activation, leading to an apoptotic cell death. FACS analysis has revealed that compound 4j arrests cells in G0/G1 phase. The presence of 3-(3-trifluoromethylphenyl)- or 3-(3-chlorophenyl)-substituent, in that order, on the 6-phenylimidazo[2,1- b ]thiazole impacts more positively than other aryl-substituents, on the anti-proliferative properties of these compounds. [ABSTRACT FROM AUTHOR]

Abstract: A new series of disubstituted alkynes was obtained by microwave induced internal splitting of the corresponding β-oxo-alkylidenetriphenylphosphoranes. The antimicrobial potential of these conjugated alkynes and phosphoranes was assayed in vitro against three Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis, Staphylococcus epidermidis), three Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) and five fungal strains (Aspergillus niger, Candida albicans, Aspergillus flavus, Candida rugosa, Saccharomyces cerevisiae). The 3-pyridylalkyne derivatives viz., 3-(6-chloropyridin-3-yl)propynenitrile (6a), 3-(2-chloropyridin-3-yl)propynenitrile (6b), ethyl 3-(6-chloropyridin-3-yl)propiolate (6c), iso-propyl 3-(6-chloropyridin-3-yl)propiolate (6d) and 3-(2,6-dichloro-5-fluoropyridin-3-yl)propynenitrile (6e) were found to be highly potent towards all tested microorganisms except E. coli. [Copyright &y& Elsevier]

Abstract: A series of novel N-(4-aryl-1,3-thiazol-2-yl)-2-(2,4-dioxo-1,3-thiazolidin-5-yl)acetamides (4a–k) and N-(1,3-benzothiazol-2-yl)-2-(2,4-dioxo-1,3-thiazolidin-5-yl)acetamide derivatives (4l–o) are synthesized and evaluated for their anti-inflammatory and antioxidant activity (DPPH radical scavenging, superoxide anion scavenging, lipid peroxide inhibition, erythrocyte hemolytic inhibition). Compounds 4k and 4l have exhibited good antioxidant activity in four assays, while compounds 4c, 4d, 4m, 4n and 4o have shown good DPPH radical scavenging efficacy. Compounds 4a, 4h, 4i, 4k, 4m and 4n have possessed excellent anti-inflammatory activity. N-[4-(o-methoxyphenyl)-1,3-thiazol-2-yl]-2-(2,4-dioxo-1,3-thiazolidin-5-yl)acetamide (4k) and N-(6-nitro-/methoxy-1,3-benzothiazol-2-yl)-2-(2,4-dioxo-1,3-thiazolidin-5-yl)acetamide (4m and 4n) have exhibited both antioxidant and anti-inflammatory activities. [Copyright &y& Elsevier]

Two series of homoleptic Pt(II)(hydrazone)Cl ( C1a - C5a ) and heteroleptic Pt(II)(hydrazone)(4-picoline). BF 4 ( C1b - C5b ) complexes were prepared and characterized by 1 H, 13 C, 19 F NMR and HR ESI-MS. Structure of C2b was confirmed by single crystal X-ray analysis. These complexes were studied for their in vitro anticancer activities in human multiple cancer cells including breast (MCF-7), liver (HepG2), lung (H460), colon (HCT116) and cervical (Hela) cancers. C1a - C5a and C1b - C5b showed considerable anticancer effect. The overall anticancer effect of all these complexes was higher in liver (HepG2) and lung (H460) cancer cell lines and the effect of C2b and C3b was observed to be the highest among these 10 complexes. Therefore, we selected C2b and C3b to study their in vitro anticancer mechanism in HepG2 and H460 cancer cells. C2b and C3b changed cancer cell morphology and inhibited cell migration. The anticancer mechanistic studies demonstrated that C2b and C3b induced cell apoptosis, as evidenced by DAPI and AO/EB staining and flow cytometry analyses. Moreover, qRT-PCR and western blotting analysis showed that H460 and HepG2 cells treated with C2b and C3b significantly increased the expression of p53, p63, p21, p15, Bax and decreased Bcl-2 and c-Myc levels. The DNA binding property of these complexes was investigated by gel electrophoresis using pBR322 plasmid DNA. Taken together, the results obtained from the present study demonstrated the potentials of this new class of Pt(II) complexes in reduction of cell viability, suppression of cell migration and acceleration of apoptosis in different cancer cells. [ABSTRACT FROM AUTHOR]

An efficient and convenient synthesis of a new series of 2-{(6 H-indolo[2,3- b]quinoxalin-6-yl)methyl}-5-aryl-1,3,4-oxadiazoles from readily available 1,2-diaminobenzene and isatins under conditions was disclosed. The 6-{(5-aryl-1,3,4-oxadiazol-2-yl)methyl}-6 H-indolo[2,3- b]quinoxalines were also prepared by the thermal cyclo-condensation reaction of 2-(6 H-indolo[2,3- b]quinoxalin-6-yl)acetohydrazides with in refluxing POCl3. The microwave-assisted synthesis was rapid and resulted in higher yield of the products at lower operating temperature with reduced waste generation in comparison with the thermal reaction protocol. [ABSTRACT FROM AUTHOR]

A convenient synthesis of a new series of N-aryl-5-(pyridin-3-yl)-1 H/3 H-1,2,3-triazole-4-carbonitriles and alkyl N-aryl-5-(pyridin-3-yl)-1 H/3 H-1,2,3-triazole-4-carboxylic acid esters is reported. The newly synthesized 5-(pyridin-3-yl)-1,2,3-triazole derivatives are evaluated for their antibacterial and antifungal activity. Some of these triazole derivatives have exhibited moderate . [ABSTRACT FROM AUTHOR]

Chromone and benzyldithiocarbazate based ligand ( ChrDTCB ) showed excellent sensitivity and selectivity for colorimetric detection of Cu 2+ in HEPES buffer 10 mM pH 7.2 in CH 3 CN/H 2 O (1:1) mixture. Upon binding with Cu 2+ ChrDTCB displayed instant color change from colorless to yellow. This sensing property of ChrDTCB was studied in detail using 1 H NMR, IR, UV–vis spectroscopy and HR-ESI–MS spectrometry. The structure of the complex of ChrDTCB and Cu 2+ was determined by single crystal X-ray analysis. No interference was observed by 30 common competing metal ions and anions showing excellent selectivity for Cu 2+ . The binding mechanism of ChrDTCB to Cu 2+ was derived from the experimental results, showed a 1:1 complex formation. The limit of detection (LOD) for Cu 2+ was calculated to be 0.12 nM. The binding of the probe to Cu 2+ was reversed completely by EDTANa 2 . ChrDTCB based solution kit was developed which afforded instant colorimetric detection of Cu 2+ far below the WHO permitted level in drinking water. Similarly, the structures and energies of ChrDTCB and ChrDTCB-Cu were theoretically investigated using DFT method, which showed the decrease in HOMO-LUMO gap of the complex as compared to the free ChrDTCB suggesting a red shift of the UV–vis absorption. Taken together all satisfactory results ChrDTCB proved to be a promising probe for instant colorimetric and spectroscopic detection of Cu 2+ in aqueous medium. [ABSTRACT FROM AUTHOR]

An abstract of the study "Microwave-Assisted Synthesis of 6-{(5-Aryl-1,3,4-oxadiazol-2-yl)methyl}-6H-indolo[2,3-b]quinoxalines" by S. Avula and colleagues is presented.

A library of hitherto unreported 1-aryl-triazole-4-carbonitrile/carboxylic acid derivatives (III) and the corresponding 3-aryl derivatives (IV) are efficiently synthesized by an elegant click chemistry protocol. [ABSTRACT FROM AUTHOR]