A rapid synthesis of isoxazolo[5,4-d]pyrimidin-4(5H)-ones under microwave irradiation with solid acid catalysis in solvent-free conditions

A rapid and efficient method for the synthesis of isoxazolo[5,4-d]pyrimidin-4（5H）-ones has been developed through cyclocondensation of 5-aminoisoxazole-4-carboxamides with orthoesters under conventional heating and solvent-free microwave irradiation with solid acid catalysis. In comparison, the reactions are faster and the yields are higher under microwave irradiation.

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.

Design and Synthesis of Pyrido[1,2-e]purin-4(3H)-one Derivatives as Potential PDE 5 Inhibitors

A novel series of pyrido[ 1,2-e]purin-4（3H）-one derivatives containing polar substituents on 5＇-position were designed and prepared as potential PDE5 inhibitors. This paper reports the synthetic routes, 1H-NMR data, and the PDE5 inhibitory activities of the target compounds. The polar piperazinyl group contained （on 5＇-position） compound, 3B2, showed the highest activity among the tested derivatives but less potency than sildenafil 1.

STUDIES ON LANGMUIR-BLODGETT FILM OF METAL COMPLEXES(Ⅰ)-PREPARATION AND CHARACTERIZATION OF THE LB FILM OF N-HEXADECYL PYRIDINIUM TETRAKIS(1-PHENYL-3-METHYL-4-BENZOYL-PYRAZOL-5-ONE)EUROPIUM,C_5H_5NC_(16)H_(33)Eu(PMBP)_4

The LB film of the title complex was prepared by dropping a benzene solution of the title complex on the surfaceof water subphase at 25±1℃.The film was deposited in Z type on various hydrophilic pretreated substrates ofquartz,CaF;and electronic conductive glass for different purposes.The π-A curve of the film shows that thecross section per molecule is 125;,which indicates that the alkyl chain of the molecule is basically perpendiculalto the surface of the substrate.UV,IR spectra and transmission electronic microscopy of the film were also obtained.

Facile synthesis of[1,2,4]triazino[4,3-b][1,2,4,5]tetrazepin derivatives by a one-pot reactions using 4-amino-3-hydrazinyl-6-methyl-1,2,4-triazin-5(4H)-one

4-Amino-3-mercapto-6-methyl-l,2,4-triazin-5（4H）-one 1 converted to 4-amino-6-methy-3-（methylthio）-1,2,4-triazin-5（4H）-one by methylation with methyl iodide.Controlled hydrazination of the resulting compound afforded 4-amino-3-hydrazinyl-6- methyl-l,2,4-triazin-5（4H）-one 2 as a building block,to the synthesis of some novel derivatives of[1,2,4]triazino- [4,3,b][1,2,4,5]tetrazepine 3-6,by the reaction with 3-chloropentane-2,4-dione,chloro acetonitrile,1,3-dichloroacetone,and methyl bromoacetate.This general synthetic procedure can be extended to the preparation of wide variety of tetrazepines using 1,2- bielectrophiles derivatives.

Enamine Configuration of 5-Methyl-2-phenyl-4- [(Z)-3-tolylamino-phenylmethylene]pyrazol-3(2H)-one

Compound 5-methyl-2-phenyl-4-[（Z）-3-tolylamino-phenylmethylene]pyrazol-3（2H）-one （C24H21N3O） crystallizes in the triclinic system, space group P1, with a = 9.267（3）, b = 9.904（4）,c = 12.035（4） A°, α = 97.896（6）, β = 103.865（6）, γ = 107.950（6）°, Mr= 367.44, Z = 2, V = 993.2（6）A°^3,Dc = 1.229 g/cm^3,μ（MoKa） = 0.077 mm^-1 and F（000） = 388. The structure was refined to R =0.0444 and wR = 0.1199 for 2903 observed reflections （I 〉 2σ（I））. The results of ^1H NMR and single-crystal X-ray diffraction studies showed the enamine character of the compound. The strong intramolecular hydrogen bonds in the large conjugate system, together with weak intermolecular C-H……π hydrogen bonding and π……π stacking, lead to the formation of a multi-dimensional supramolecular network.

Synthesis and Crystal Structure of 4-Bromo-5-ethoxy-3-methyl-5- (naphthalen-1-yl)-1-tosyl-1H-pyrrol-2(5H)-one

The title compound 4-bromo-5-ethoxy-3-methyl-5-（naphthalen-l-yl）-l-tosyl-lH- pyrrol-2（5H）-one 1 （C24H22BrNO4S, Mr = 500.40） has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/n with a = 8.8562（15）, b = 18.118（3）, c = 14.055（2）A, β = 99.855（3）^o, V= 2221.9（6）A3, Z = 4, Dc = 1.496 g/cm^3,μ= 1.975 mm^-1, 2 = 0.71073A, F（000） = 1024, R = 0.0607 and wR = 0.1371.

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.

An effcient one-pot multi-component synthesis of 3,4,5-substituted furan-2(5H)-ones catalyzed by tetra-n-butylammonium bisulfate

A facile one-pot synthesis of 3,4,5-substituted furan-2（5H）-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using tetra-n-butylammonium bisulfate as a catalyst has been developed.

Vitamin B12: An efficient type catalyst for the one-pot synthesis of 3,4,5-trisubstituted furan-2(5H)-ones and N-aryl-3-aminodihydropyrrol-2-one-4-carboxylates

Vitamin B12 was applied as catalyst for the one-pot three-component synthesis of 3,4,5-trisubstituted furan-2（5H）-ones from the condensation between aldehydes, amines and dialkylacetylendicarboxylates at ambient temperature in Et OH. In addition, N-aryl-3-aminodihydropyrrol-2-one-4-carboxylates were synthesised using mentioned catalyst at ambient temperature in Et OH from condensation between formaldehyde, amines, and dialkylacetylenedicarboxylates. This methodology has number of advantages such as： use of green and nonhazardous catalyst, clean work up, short reaction times,high yields and no need to column chromatography.

An efficient regioselective sonochemical synthesis of novel 4-aryl-3-methyl-4,5-dihydro-1H-pyrazolo[3,4-b]pyridin-6(7H)-ones

An efficient ultrasound-assisted preparation of a series of novel 4-aryl-3-methyl-4,5-dihydro-l//-pyrazolo[34-b]pyridin-6（7H）ones via the reaction of 5-amino-3-methyl-1H-pyrazole,Meldrum＇s acid and various arylaldehydes using one-pot three-component approach is described.This rapid method produced the products in short reaction times（3-4 min） and excellent yields（87-95%）.

New efficient synthesis of 2,5,6-trisubstituted oxazolo[5,4-d]pyrimidi-7(6H)-ones via an oxazolyliminophosphorane

A new efficient synthesis of 2,5,6-trisubstituted oxazolo（5,4-d]pyrimidi-7（6H）-ones by consecutive azaWittig reaction was developed.The sequential three-component reaction of oxazolyliminophosphorane4,isocyanates and amines produced 2,5,6-trisubstituted oxazolo[5,4-d]pyrimidi-7（6H）-ones 7 in good overall yields in the presence of catalytic amount of EtONa.

Design, Synthesis, and Evaluation of 3-（（4-（t-Butyl）-2-（2- benzylidenehydrazinyl）thiazol-5-yl）methyl）quinolin- 2（1H）-ones as Neuraminidase Inhibitors

A series of novel 3-（（4-（t-buty-）-2-（2-benzylidenehydrazinyl）thiazol-5-yl）methyl）quinolin-2（1H）-ones （7a--7z） were designed, synthesized and evaluated for their ability of inhibiting neuraminidase （NA） of influenza H1N1 virus. Some compounds displayed moderate influenza NA inhibitory activity. Compound 71 with the scaffold of 2-（2-（2-methoxybenzylidene）hydrazinyl）thiazole was the best one, exhibiting moderate NA inhibitory activity with ICs0 of 44.66 ~tmol/L. Structure-activity relationship showed that compounds with methoxy or hydroxy groups at the ortho position, fluorine and nitro groups at the meta position and chlorine and bromine groups at the para posi- tion of phenyl ring were more active. Docking study indicated that compound 71 has important interactions with some key residues （including Asp151, Glu119, Arg292, Tyr406, and Asn347） and binds to 430-cavity adjacent to NA active site.

Reaction of 2,3-Dihydro-1,5-benzothiazepines and Phenylacetyl Chloride in the Presence of Triethylamine:A New Aspect on the Formation Mechanism of Dihydro-1,3-oxazin-4-one Derivatives

2a,4-Disubstituted 2,2a,3,4-tetrahydro-2-phenyl-1H-azeto[2,1-d][1,5]benzothiazepin-1-ones, as well as 2-substi- tuted 2,3-dihydro-3-phenylacetyl-2-styryl-benzothiazoles and 4a,6-disubstituted 3-benzyl-4a,5-dihydro-2-phenyl- 1H,6H-[1,3]oxazino[2,3-d][1,5]benzothiazepin-1-ones, were obtained from the reaction of 2,4-disubstituted 2,3-dihydro-1,5-benzothiazepines with phenylacetyl chloride in the presence of triethylamine. The mechanism for the formation of 4a,5-dihydro-1H,6H-[1,3]oxazino[2,3-d][1,5]benzothiazepin-1-ones, 2,3-dihydro-1,3-oxazin-4-one derivatives, was suggested.

Synthesis of pyrazine-2,3-dicarbonitrile and 1,2,4-triazine-5(4H)-one derivatives from furan-2,3-diones

The reaction of furan-2,3-diones with S-methylisothiosemicarbazide hydroiodide yielded novel 1,2,4- triazine-5（4H）-ones, and reaction of furan-2,3-diones with diaminomaleonitrile led to the formation of pyrazine-2,3-dicarbonitrile derivatives, and the hydrolysis of these products led to the formation of more new pyrazine-2,3-dicarbonitrile derivatives. These compounds are potential herbicides and pesticides.

Structure-based design and synthesis of 5-benzyl-2-phenylpyrimidin-4(3H)-one derivatives as novel MEK1 inhibitors

Previous studies have shown that Ras/Raf/MEK/ERK signaling pathway is up-regulated in almost all cancer cells.Blocking of this pathway by MEK inhibition is an efficient therapeutic approach of cancer.In the present study,we described the discovery of 5-benzyl-2-phenylpyrimidin-4（3 H）-one as a novel skeleton of allosteric MEK inhibitor.All acquired target compounds exhibited modest potency to inhibit MEK1 in Raf-MEK cascading assay,and docking studies revealed that the binding mode of the most potent compound（SJ3） was very similar to that of the well known diarylamine-based inhibitor（PD0325901）.The results provided valuable guidance for further optimizations on this novel scaffold to achieve druggable molecules.

Un-catalyzed tandem Knoevenagel-Michael reaction for the synthesis of 4,4'-(arylmethylene)bis(1H-pyrazol-5-ols)in aqueous medium

An environmentally benign un-catalyzed one-pot synthesis of 4,4＇-（arylmethylene）bis（1H-pyrazol-5-ols） has been reported via tandem Knoevenagel-Michael reaction of aldehydes with two equivalents of 3-methyl-1-phenyl-1H-pyrazol-5（4H）-one in aqueous medium.

苏木心材中一个新黄酮类化合物

目的:从苏木Caesalpinia sappan中寻找新的活性成分。方法:用溶剂萃取及硅胶正相色谱进行活性成分的分离纯化,根据理化性质、光谱数据进行结构鉴定。结果:从苏木95%乙醇提取物中分离得到了9个化合物:3,8-dihydroxy-4,10-dimethoxy-7-oxo-[2]benzopyrano[4,3-b][1]benzopyran-7-(5H)-one(1),3-deoxysappanchal-cone(2),sappanchalcone(3),3-deoxysappanone B(4),鼠李素(rhamnetin,5),原苏木素C(protosappanin C,6),3,7-di-hydroxy-chroman-4-one(7),己二酸二甲酯(8),胡萝卜苷(daucosterin,9)。结论:化合物1为新化合物,化合物7,8为首次从该植物中分离得到。药理筛选结果表明,化合物3对多种癌细胞株具有一定的抑制活性。

一测多评法测定毛郁金中5种成分

目的建立毛郁金药材中不同成分同时测定的一测多评法。方法以毛郁金中莪术二酮为指标,建立莪术二醇、ocathydro-1,4-dihydroxy-1,4-dimethyl-7-(propan-2-ylidene)azulen-5(1H)-one、原莪术醇和姜黄素的相对校正因子,在考察相对校正因子的重现性后,进一步采用外标法对一测多评法所计算出的成分含量进行验证。结果 10批毛郁金药材中,各成分采用相对因子计算的含量与采用外标法计算的结果无显著差异。结论以莪术二酮为参照物,采用一测多评测定和计算其他4种成分含量的方法是可行的,结果较为准确。

Selective amination of the mucohalic acid derivatives

An efficient synthesis of 4,5-diamino-3-halofuran-2（5H）-ones has been developed based on a sequential acylation and bisamination of mucohalic acids. The /5- and y-amination products have also been prepared with high regioselectivity. This reaction shows some advantages in terms of its simple operation and readily available but highly functionalized starting material. All products gave satisfactory IR. 1H NMR. 13C NMR and HRMS.