Guirong Qu

Ionic liquid mediated and promoted eco-friendly preparation of thiazolidinone and pyrimidine nucleoside-thiazolidinone hybrids and their antiparasitic activities

Without any catalyst, 2,3-disubstituted-1,3-thiazolidin-4-one derivatives were synthesized efficiently via the three-component reaction of aldehyde, amine and mercaptoacetic acid in [bmim][PF(6)]. The whole procedure is simple and straightforward and no aqueous work-up is needed. By employing this protocol, a series of novel pyrimidine nucleoside-thiazolidin-4-one hybrids were prepared and their preliminary antiparasitic activities were also studied and reported.

Ionic liquid-promoted multi-component reaction: novel and efficient preparation of pyrazolo[3,4-b]pyridinone, pyrazolo[3,4-b]-quinolinone and their hybrids with pyrimidine nucleoside

The utilization of an ionic liquid, [bmim][BF4] as both reaction medium and promoter for a multi-component reaction of aldehyde (1) and 5-amino-3-methyl-1-phenylpyrazole (2) with Meldrum acid (3) or dimedone (5) is studied. From this reaction, pyrazolo[3,4-b]pyridinone (4) and pyrazolo[3,4-b]quinolinone (6) derivatives were prepared in high yields. This novel procedure showed such advantages as environmentally benign nature, enhanced efficiency, simple operation process, and mild reaction conditions. As an application, the procedure was successfully used in the preparation of a set of pyrimidine nucleoside–pyrazolo[3,4-b]pyridine and pyrazolo[3,4-b]quinolinone hybrids with potential biological activities.

Ionic liquid promoted preparation of 4H-thiopyran and pyrimidine nucleoside-thiopyran hybrids through one-pot multi-component reaction of thioamide

One-pot multi-component reactions of aldehydes, cyanothioacetamide and malononitrile promoted by ionic liquid proved to be an efficient way for the synthesis of thiopyran derivatives. Without any added catalyst, both aromatic and aliphatic aldehydes participated in this reaction smoothly. As an application of this method, a pyrimidine nucleoside-thiopyran chimera with potential biological activities was obtained in high yield from 5-formyl-2’-deoxyuridine. In addition, the ionic liquid used can be easily recovered and effectively reused for at least 5xa0times.

Controllable Synthesis of Pyrazolo[3,4-b]pyridines or Substituted Malononitrile Derivatives through Multi-Component Reactions in Ionic Liquid

A multi-component reaction of aldehyde, malononitrile, and 5-amino-3-methyl-1-phenylpyrazole was carried out smoothly in [bmim][BF4] without any added catalyst. Through this reaction, pyrazolo[3,4-b]pyridines or substituted malononitrile derivatives were obtained conveniently and controllably at different temperatures. The ionic liquid used can be easily recovered and efficiently reused for at least five runs.

Microwave‐Assisted Solid‐State Synthesis and Characterization of Thiohydantoin Derivatives

Abstract A new and efficient solid‐state method for the preparation of thiohydantoins is reported. With this method, twelve thiohydantoin compounds have been synthesized in good to excellent yields (81–92%). In addition, this method has the advantages of high yields, a cleaner reaction, simple methodology, and short reaction times.

Syntheses, Photoluminescent Properties, and Structural Investigation of Five Complexes based on a New T-Shaped 2-(Pyridin-3-yl)-4,6-Pyrimidine Dicarboxylic Acid Ligand: Structure Evolution from One-dimensional Chains to Three-dimensional Architectures

A series of structurally diverse coordination polymers, [Mn(ppmdc)(H2O)2]n (1), [Cu(ppmdc)(H2O)2]n (2), {[Co(ppmdc)][Co(ppmdc)(H2O)]}n (3), [Zn(ppmdc)(H2O)]n (4), and [Cd(ppmdc)]n (5) (H2ppmdcu2009=u20092-(pyridin-3-yl)-4,6-pyrimidine dicarboxylic acid) were obtained from metal salts and H2ppmdc under hydrothermal conditions. Single crystal X-ray structural analysis reveals that complexes 1–5 have different structures, ranging from one- to three-dimensions, which are mainly due to the different metal ions, and especially the coordination mode of the H2ppmdc ligand. Complexes 1 and 2 are 1D coordination polymers, in which the ppmdc2– ligand adopts a bis-(bidentate) mode to link metal ions. Complexes 3 and 4 feature a 2D metal-organic framework with Schlafli topologies of (4.62) (42.62.82) and (4.82), respectively, in which the metal ions are bridged by μ3-ppmdc2– ligands. Complex 5 possesses a 3D nanotubular metal-organic framework with a point symbol of (49.66) topology built up from the 6-connected ppmdc2– ligands and Cd(ii) ions. The thermal properties of complexes 1–5 have been determined. Moreover, investigation of photoluminescent properties reveals that the configuration of ppmdc2– resulting from metal-directed coordination has a profound effect on the fluorescence emissions of complexes 4 and 5.

4-Bromo-5-[(2-bromo­ethyl)­sulfanyl]-1,3-dithiole-2-thione

The title compound, C5H4Br2S4, consists of a statistically planar, 4-bromo-1,3-dithiole-2-thione unit [maximum deviation from the ring plane 0.001u2005(2)u2005Å], with a bromoethylsulfanyl substituent in the 5-position. In the crystal structure, weak intermolecular S⋯S [3.438u2005(15) and 3.522u2005(15)u2005Å] and S⋯Br [3.422u2005(14) and 3.498u2005(14)u2005Å] interactions generate a three-dimensional supramolecular architecture.

Dimethyl 6,6′-dicyano-2,2′-bipyridine-3,3′-dicarboxyl­ate

In the title compound, C16H10N4O4, the two pyridine rings are twisted by 44.41u2005(2)° and the ester groups form dihedral angles of 48.77u2005(4) and 45.75u2005(2)° with the corresponding pyridine rings. The crystal structure is stabilized by intermolecular C—H⋯O hydrogen bonds and π–π stacking interactions between the pyridine rings [centroid-to-centroid distance 3.797u2005(2)u2005Å].

6-Amino-3-methyl-4-(4-nitro­phen­yl)-1-phenyl­pyrazolo[3,4-b]pyridine-5-carbonitrile

The title compound, C20H14N6O2, contains four rings. The dihedral angle between the pyridine ring and the pyrazole ring is 1.9u2005(1)°, i.e. almost coplanar, which gives rise to a conjugated structure. The dihedral angle between the nitro-substituted phenyl ring and the pyridine ring is 76.3u2005(1)° and that between the pyrazole ring and the non-substituted phenyl ring is 40.5u2005(1)°. In the crystal structure, symmetry-related molecules are linked by N—H⋯O and C—H⋯N hydrogen bonds.