SYNTHESIS OF 4-SUBSTITUTED (OR 4-SPIRO) 3-OXABICYCLO[3.1.0]HEXAN-2-ONE

Cyclopropanedicarboxylic anhydride can be converted to 4-substituted (or 4-spiro-)3-oxabicyclo[3.1.0]hexan-2-one by addition of Grignard (or α,ω-di-Crignard) reagents in ether or tetrahydrofuran solution.

THE REDUCTION OF 4,4-DISUBSTTTUTED 3-OXABICYCLO[3.1.0]HEXAN-2-ONE

Reduction of the title compounds with LiAIH_4 or DIBAL (diisobutyl aluminium hydride) leads to the formation of 2-(disubstituted hydroxymethyl)cyclopropanemethanol (2)or 4,4-disubstituted 3-oxabicyclo[3.1.0] hexan-2-ol (3) respectively.

Synthesis of 4-substituted 3-oxabicyclo[3.1.0]hexan-2-one

Cyclopropanedicarboxylic acid anhydride can be converted to 4-substituted 3-oxabicyclo- [3.1.0]hexan-2-one by reaction with Grignard reagents in ether or tetrahydrofuran solution.

Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One

New cobalt(II) complex, [Co(O2C15H11N2S)2(OH2)2]∙2H2O (1∙2H2O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)2∙6H2O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H2O. Compound 1∙2H2O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H2O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H2O displayed moderate activity (10 ∙2H2O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).

Visible-Light-Induced Cascade Azidation/Cyclization of Activated Alkenes to Synthesize Azidated Indolo[2,1-a]isoquinolines

An efficient visible-light-induced radical cascade azidation/cyclization of 2-aryl indoles with trimethylsilyl azide(TMSN3)has been developed using organic dye Rose Bengal as the photocatalyst.This method did not require metal catalysts and additives,and used air as the oxidant to obtain diverse indolo[2,1-a]isoquinolin-6(5H)-ones in moderate to good yields.Mechanistic studies demonstrated that the reaction proceeded via a radical pathway.

Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One

New cobalt(II) complex, [Co(O2C15H11N2S)2(OH2)2]∙2H2O (1∙2H2O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)2∙6H2O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H2O. Compound 1∙2H2O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H2O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H2O displayed moderate activity (10 ∙2H2O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).

Selenium-catalyzed oxidative carbonylation of 2-aminobenzyl alcohol to give 1,4-dihydro-2H-3,1-benzoxazin-2-one

An efficient,economical,and phosgene-free approach was developed for the preparation of l,4-dihydro-2H-3,l-benzoxazin-2-one from 2-aminobenzyl alcohol.In terms of its key features,this reaction uses the cheap and recyclable non-metal selenium as a catalyst instead of the noble metal palladium;carbon monoxide as a carbonylation agent instead of virulent phosgene or one of its derivatives;and oxygen as an oxidant.The selenium-catalyzed oxidative carbonylation reaction of2-aminobenzyl alcohol proceeded efficiently in a single pot in the presence of triethylamine to afford l,4-dihydro-2H-3,l-benzoxazin-2-one in 87%yield.Furthermore,the selenium catalyst was readily recovered and recycled,affording a product yield of 80%after five cycles.

Highly efficient synthesis of 2,3-dihydroquinazolin-4(1H)-ones catalyzed by heteropoly acids in water

Heteropoly acids efficiently catalyzed the cyclocondensation reaction of anthranilamide with aldehydes in water at ambient temperature and afforded the corresponding 2,3-dihydro-4（1H）-quinazolinones compounds in good to excellent yields.This method provides mild reaction conditions and clean reaction profiles,using a small quantity of catalyst and a simple workup procedure.

An efficient synthesis of 2,2′-arylmethylene bis-(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) and 1,8-dioxooctahydroxanthenes using ZnO and ZnO-acetyl chloride

2,2'-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) 4l-s produced from reaction between dimedone with various aldehydes in acetonitrile using ZnO as a catalyst;whereas in the presence of ZnO-acetyl chloride catalysts the reaction is limited to give only 1,8-dioxo-octahydroxanthenes 3a-k in very good yields.

Synthesis,Bioactivity and Crystal Structure Analysis of Novel Benzo[d]isothiazol-3(2H)-ones

Two compounds,3-oxo-N-o-tolylbenzo[d]isothiazole-2（3H）-carboxamide （1） and N-（2-methoxyphenyl）-3-oxobenzo[d]isothiazole-2（3H）-carboxamide （2）,were synthesized from the initial compound benzo[d]isothiazol-3（2H）-one （BIT） and characterized by 1 H NMR,IR and elemental analysis,respectively.The single crystals of compounds 1 and 2 were obtained and determined by X-ray diffraction analysis.The preliminary results of biological activity experiment show that some of the title compounds exhibited a favorable antimicrobial activity.

Synthesis of some new 3-[5-(2-oxo-2H-3-chromenyl)-1,3-oxazol-2-yl]-1,3-thiazolan-4-ones as antimicrobials

A series of some new 2-imino-5-[（Z）-1-（4-methylphenyl）methylidene]-3-[5-（2-oxo-2H-3-chromenyl）-1,3-oxazol-2-yl]-1,3- thiazolan-4-ones 5a-j has been synthesized and assayed for their antibacterial activity against Gram-positive bacteria viz.Bacillus subtilis（ATCC 6633）,Staphylococcus aureus（ATCC 6538p） and Micrococcus luteus（IFC 12708）,and Gram-negative bacteria viz. Proteus vulgaris（ATCC 3851）.Salmonella typhimurium（ATCC 14028） and Escherichia coli（ATCC 25922）.Among the screened compounds,5d,5e,5f,5g,and 5j exhibited potent inhibitory activity compared to standard drug,and emerged as potential molecules for further development.

Photo-/electrocatalytic functionalization of quinoxalin-2(1H)-ones

The photo-/electrocatalytic functionalization of quinoxalin-2(1H)-ones has emerged as a promising and powerful approach for post-synthetic modification of quinoxalin-2(1H)-ones.This review provides an overview of recent developments in photo-/electrocatalytic functionalization of quinoxalin-2(1H)-ones including arylation,alkylation,fluoroalkylation,amination,phosphorylation,acylation,alkoxylation,thiolation,silylation,and annulation.The reaction scope and the related mechanism are also well discussed.

A bifunctional and recyclable catalyst:Amine and ionic liquid grafting on MOFs for the one-pot synthesis of N-aryl oxazolidin-2-ones

A bifunctional heterogeneous catalyst was designed and synthesized,denoted DMEDA/IL–NH2-MIL-101.The structure and physical-chemical characterization of DMEDA/IL–NH2-MIL-101 and its precursors were characterized by SEM,N2 adsorption-desorption,XPS,FT-IR,PXRD,elemental analysis,and TGA techniques.The date showed that the two catalytic components of N,N-dimethylethylenediamine(DMEDA)and 1-butyl-3-methylimidazolium bromide(BmimBr)were chemically immobilized in NH2-MIL-101 nanocages.The amine of DMEDA was grafted onto carrier NH2-MIL-101 by N–Cr coordinate covalent bonds and the ionic liquid of BmimBr(IL(Br-))was anchored in the NH2-MIL-101 nanocages by'ship-in-a-bottle'method,in which the amidogen of NH2-MIL-101 condensed with N,N-carbonyldiimidazole(CDI)firstly,and then alkylated with 1-bromo butane.This novel heterogeneous catalyst with two different active sites can efficiently catalyze the synthesis of N-aryl oxazolidin-2-ones from carbon dioxide(CO2),epoxides,and anilines in one-pot under mild solvent-free conditions.It not only showed good stability and recoverability after five cycles but also exhibited shape selectivity for the substrate due to the synergic catalysis of amine,ionic liquid,and NH2-MIL-101.This novel bifunctional material is a promising solid catalyst for the green synthesis of N-aryl oxazolidin-2-ones.

The Synthesis of 7-[1-Aza-2-(dimethylamino)vinyl]-4-methylhydroquinolin-2-ones and their Isomerism in Different Solvents

The reaction of 7-amino-4-methyl-2(1H)-quinolone 1 and its 6-methyl derivative 2 with Vilsmeier reagent (DMF and POCl3) afforded 7-[1-aza-2-(dimethylamino)vinyl]-4-methyl-hydroquinolin-2-one 3 and 7-[1-aza-2-(dimethylamino)vinyl]-4,6-dimethylhydroquinolin- 2-one 4, respec-tively. H-1-NMR analysis in different solvents indicated that isomerism occurred due to hindered rotation around the (CH3)(2)N-C:N o -bond. The rotational energy barrier of 3 was calculated.

Synthesis and anti-HBV activity of novel 5-substituted pyridin-2(1H)-one derivatives

Four novel 5-substituted pyridine-2(1H)-one derivatives were designed and synthesized by using addition-elimination reactions.The structures of these novelly synthesized compounds were verified by ~1H NMR,ESI-MS and single crystal X-ray diffraction.Furthermore,all four compounds(most notably compound 7a) were found to be highly efficient against hepatitis B virus (HBV) in cultured HepG2 2.2.15 cell,making them promising drug candidates for potential bioactive molecule against hepatitis B.

Synthesis and Crystal Structure of 2-Ethoxy-3-n-butyl-benzofuro [2,3-d]pyrimidin-4(3H)-one

The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4（3H）-one （C16H18N2O3, Mr = 286.32） has been prepared and determined by singlecrystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 13.7167（14）, b = 13.113（1）, c = 8.378（1） A, β = 98.992（2）^o, V = 1488.4（3） A^3, Z = 4, Dc = 1.278, F（000） = 608, μ = 0.089 mm^-1, MoKa radiation （2 = 0.71073）, R = 0.0498, wR = 0.1238 for 2336 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals that all ring atoms in the benzo[4, 5]furo [2,3-d] pyrimi- dinone moieties are almost coplanar.

Extraction of palladium(Ⅱ) from hydrochloride solutions with 2-n-octyl-4-isothiazolin-3-one as novel extractant

Solvent extraction of palladium （Ⅱ） from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one （OIT）/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.96 % and 98.26 % palladium （Ⅱ） could be effectively extracted with 0.018 mol·L^-1 OIT/cyclohexane of 0.1 and 4.0 mol·L^-1 HCl medium, respectively. Nonpolar solvent and low acidity could improve the extracting efficiency, and successfully strip palladium （Ⅱ） from the loaded organic phase was achieved with 0.5 mol·L^-1 （NH2）2CS solution. It was proposed that the extraction of Pd com-plexes from HCl medium proceeded through the ion-association mechanism by slope method, NMR and FF-IR spectra.

An efficient synthesis of 2,2-bis(1H-indol-3-yl)-2H-acenaphthen-1-one catalyzed by recyclable solid superacid SO_4^(2-)/TiO_2 under grinding condition

An efficient synthesis of symmetrical 2,2-bis（1H-indol-3-yl）-2H-acenaphthen-1-one is achieved via a reaction of acenaphthe-nequinone and indoles catalyzed by solid superacid SO4^2-/TiO2 under solvent-free conditions at room temperature by grinding, which provides an efficient route to the synthesis of symmetrical 2,2-bis（1H-indol-3-yl）-2H-acenaphthen-1-one.This procedure offers several advantages including solvent-free conditions,excellent yields of products,simple work-up as well as reuse of catalysts which makes it a useful and attractive protocol for the synthesis of these compounds.

Synthesis and Crystal Structure of 1-(4-Fluorophenyl)-2-hexylthiobenzo[4,5]-furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5(1H)-one

The crystal structure of the title compound 1-（4-fluorophenyl） -2-hexylthio-benzo [4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5（1H） -one（C23H21FN4O2S,Mr = 436.5） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic,space group P21/n with a = 13.9854（3） ,b = 17.2678（4） ,c = 18.1828（5）A,β = 99.364（2） °,V = 4332.58（18） A^3,Z = 4,Dc = 1.338,F（000） =1824,μ = 0.185 mm^-1,MoKa radiation（λ = 0.71073） ,R = 0.0538 and wR = 0.1162 for 4728 observed reflections with I 〉 2σ（I） . X-ray diffraction analysis reveals the fused rings of benzo[4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a] pyrimidin-5（1H） -one system are nearly coplanar. The crystal packing is mainly stabilized by weak intermolecular C-H···O hydrogen bond and π-π interactions.

Synthesis,Crystal Structure and Cytotoxic Activities of Oxazolidin-2-one Derivatives

Four cytotoxic oxazolidin-2-one derivatives were prepared from alkynyl alcohol and isocynate with high yields of 83～95%, and their structures were characterized by IR, H-RESI-MS and NMR analysis. Meanwhile, the crystal of （Z）-4-benzylidene-3-ethyl-1-oxa-3-azaspiro[4.4] nonan-2-one （5a） was obtained and determined by X-ray single-crystal diffraction. Crystal data： monoclinic system, space group P121/c1, a = 10.9284（2）, b = 9.47510（10）, c = 14.2510（2） ？, β = 111.917（2）o, V = 1369.01（3） ？3, Z = 4, F（000） = 552.0, Dc = 1.248 Mg/m3, μ = 0.652 mm-1, R = 0.0473 and wR = 0.1207 for 2699 independent reflections （Rint = 0.0206） and 2581 observed ones （I 〉 2σ（I））.