Design, Synthesis, and Hypnotic Activity of Pyrazolo [1,5-a]pyrimidine Derivatives

On the basis of the Zaleplon structure, novel pyrazolo[1,5-a]pyrimidines were designed and prepared for studies on their hypnotic activity. This paper reported the synthesis of twelve new 5-methyl-7-substituted-pyrazolo[1,5-a]pyrimidine-3-carbonitrile derivatives by using simple starting materials such as propane dinitrile and triethyl orthoformate. The structures of the derived target compounds were confirmed by their IR and ^1H-NMR spectroscopic data. The preliminary pharmacological evaluations indicated that some compounds showed hypnotic activity, whilc derivative 1c was the most potent one.     

Synthesis of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives

A series of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives have been synthesized by utilizing the coupling of methyl 3-methoxy-4-hydroxy-5-bromocinnamate with cuprous phenylacetylide as the key step.The structures of the new compounds were confirmed by1H NMR,IR and MS.The structure of compound 14 was further confirmed by single crystal X-ray.Compound 17 showed cytotoxic activity against human lung carcinoma A549.     

DFT Study on the （S）-Proline-catalyzed Direct Aldol Reaction between Acetone and 4-Nitrobenzaldehyde

1 INTRODUCTION Aldol reaction, one of the most important C–C bond-formation reactions, is widely utilized in orga- nic synthesis[1]. Extensive efforts have been donated to the development of catalytic stereo-selective va- riants of this reaction[2]. However, the direct aldol reaction between unmodified carbonyles would be the most attractive synthetic alternative. Proline-catalyzed intermolecular direct aldol reac- tion between acetone and 4-nitrobenzaldehyde was first reported by List…     

Crystal Structures of Fluoride and Chloride Complexes of Tris[（2-benzimidazolyl）methyl]amine

The crystal structures of fluoride and chloride complexes of tris[（2-benzimidazolyl）methyl]amine 1 were characterized by X-ray crystallography. 1 adopts （73 symmetrical geometry and cone-like conformation so as to allow its three NHs to associate with the anions through hydrogen bonds. Despite the different sizes of the anions, the two crystals are unexpectedly isostructural. The binding ability of the anions of 1 in solution was also studied by using of UV-vis spectroscopy.     

Microstructure Analysis of Nylon 66 by WAXD and SAXS

IntroductionNylon 66,one of the most successfulcommercial polyamides,has been widely usednowadays as an engineering plastic in many fields.The development of the structure of nylons is acontinuing area of their technological and scientificstudy.The structure of nylon 66 during thephotoinduced decomposition process has beenstudied by resonance Raman[1] ,and the effect oftranscrystalline layers have been investigated[2— 4] .Moreover,the crystallization and meltingbehavior[5] have been learned …     

A Convenient Synthesis of 2-Arylnaphtho[1,2-d]oxazole Derivatives Promoted by Triethylamine

A variety of 2-arylnaphtho[ 1,2-d]oxazole derivatives were efficiently synthesized in moderate to high yields by the reaction of aromatic aldehydes with 1-amino-2-naphthol derivatives in the presence of triethylamine in refluxing ethanol in air. Seven new 2-arylnaphtho[1,2-d]oxazole derivatives were obtained and characterized by the spectral data and elemental analysis. In addition, the X-ray crystal structures of 2-[4-（N,N-dimethylamino）phenyl]naphtho[ 1,2-d] oxzole （3d） and 1, 1＇-bis（naphtho[ 1,2-d]oxazol-2-yl）ferrocene （3n） have been determined.     

Study on the Stereoselective Synthesis of Carbapenem Sidechain （2S,4S）-4-Acetylsulphanyl-2- [（S）-l-phenylethylcarbamoyl]- pyrrolidine-l-carboxylic Acid 4-Nitrobenzyl Ester

A stereoselective and economic synthesis of the carbapenem sidechain (2S, 4S)-4-ace-tylsulphanyl-2- [ (S) 1-phenylethyl-carbamoyl] pyrrolidine-l-carboxylic acid 4-nitrobenzyl ester was developed. Due to the effect of spatial hindrance, only the (2S,4S) diastereomer 3 was obtained by coupling 1 and the inexpensive racemic 2 catalyzed by EEDQ.     

Preparation and Standard Formation Enthalpy of 2－Amino－4,6－dimethylpyrimidine and Its Related Complexes of Copper

IntroductionThe pyrimidine and its derivatives are knownto possess extraordinary biological properties thatare generally distinguished qualitatively by havingbeen used as pesticide,herbicide,bactericide,andmedicine intermediates[1] .A survey of these appli-cations and a number of the related variations thathave been developed recently,such as the extraor-dinary effective herbicide of sulfonyl sulfourea,re-veals that the biological properties are just becauseof the wide existence of pyrimidine …     

Asymmetric Michael Addition of Activated Alkenes to Nitro Alkenes Catalyzed by Organic Catalyst

Enantioselective Michael addition is one of the most powerfulbond-forming reaction in organic synthesis. [1] A mong the Michael acceptors, nitro alkenes are very attractive, because the nitro group is the most electron-withdrawing group known and it can serve as masked functionality to be further transformed after the addition has taken place. [2] Recently, asymmetric Michael reactions catalyzed by organic catalyst have draw much attention.[3]     

Synthesis and Crystal Structure of 3-（2-Hydroxy-phenyl）-5-（2-methylphenyl）-6-thoxycarbonyl-cyclohexen-2-one

1 INTRODUCTION The molecular assembly of one- or multi-dimen-sional aggregation by hydrogen bonds is now an im-portant subject of supramolecular chemistry and crys-tal engineering[1, . Supramolecular structures formed 2]via intermolecular hydrogen bonds X–H…X or C–H…X (X = O, Cl, N, et al.) are very common inorganic compounds[3~12], and they generally possessdifferent properties due to these hydrogen bonds. Concerning about the spectra of benzene-contai-ning…     

Synthesis and Crystal Structure of Trans-4-[(5-(2,4-Dichlorophenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl)methyleneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one

The title compound trans-4-[(5-(2,4-dichlorophenoxy)-3-methyl-1-phenyl-1H-pyra-zol-4-yl)methyleneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 (C28H23Cl2N5O2, Mr = 532.41) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1 with a = 8.9438(4), b = 11.6065(5), c = 14.2215(6) , α = 112.566(1), β = 92.324(2), γ = 102.91(1)o, V = 1315.65(10) 3, Z = 2, Dc = 1.344 g/cm3, μ(MoKα) = 0.282 mm-1, λ = 0.71073 , F(000) = 552, the final R = 0.0587 and wR = 0.1578 for 5071 observed reflections (I > 2σ(I)). X-ray analysis reveals that the product is a thermodynamically stable trans isomer. Intra-and intermolecular C(12)-H(12)···O(1) and C(28)-H(28)···O(1)#1 hydrogen bonds were observed in the title compound.     

A Three-dimensional Porous Metal-organic Framework Based on Cyano Unit and 1,4-Bis（1,2,4-triazol-1-yl）butane（btb）：{[Cu_8（btb）_2（CN）_8].3H_2O}_n

The title coordination polymer 1,{[Cu8(btb)2(CN)8].3H2O}n(btb = 1,4-bis(1,2,4-triazol-1-yl)butane),has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction.Complex 1 crystallizes in monoclinic,space group C2/c with a = 1.2938(3),b = 1.9422(5),c = 0.9406(2) nm,β = 121.891(4)°,V = 2.0066(9) nm3,C24H30Cu8N20O3,Mr = 1155.00,Dc = 1.912 g/cm3,μ(MoKα) = 4.209 mm?1,F(000) = 1140,GOF = 1.184,Z = 2,the final R = 0.0634 and wR = 0.1503 for I > 2σ(I).In complex 1,one-dimensional CuCN zigzag chains are linked by triazolyl groups of btb ligands to form two-dimensional networks,which are further bridged by 1,4-butyl moieties of btb ligands to fabricate a three-dimensional order framework,in which one-dimensional ellipsoid-like channels are observed.     

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) ,β = 99.364(2) °,V = 4332.58(18) 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 and Crystal Structure of 2-Ethoxy-spiro[2H-1, 4,2-benzoxazaphosphorine-3（4H）, 1＇-Cycloheptane] 2-Oxide

1 INTRODUCTION α-Aminophosphonates are an important class of compounds since they are considered as structural analogues of the corresponding α-amino acids. Their utilities as enzyme inhibitors, antibiotics, pharma- cological agents and many other applications are well documented[1~5]. Moreover, cyclic α-amino- phosphonates, one important kind of α-aminopho- sphonates, have attracted chemists’ interests for a long time[6~11]. In order to search for potent and selec- tive herbicides a…     

Synthesis and Crystal Structure of 1-Methylsulfinyl-1-methylthio-2-cyano-2-phenylethylene

1　ＩＮＴＲＯＤＵＣＴＩＯＮＤｉｔｈｉｏａｃｅｔａｌｓ[1 3]ｈａｖｅｄｅｍｏｎｓｔｒａｔｅｄｔｈｅｉｒｐｏｔｅｎｔｉａｌｆｏｒｔｈｅｓｙｎｔｈｅｓｉｓｏｆｈｅｔｅｒｏｃｙ ｃｌｅｓ,ｔｈｅｒｅｆｏｒｅ ,ｔｈｅｉｒｓｙｎｔｈｅｓｉｓａｎｄｒｅａｃｔｉｏｎｓｈａｖｅａｔｔｒａｃｔｅｄｍｕｃｈａｔｔｅｎｔｉｏｎ ,ｂｕｔｖｅｒｙｌｉｔｔｌｅｈａｓｂｅｅｎｒｅｐｏｒｔｅｄａｂｏｕｔｔｈｅｏｘｉｄａｔｉｏｎｏｆｄｉｔｈｉｏａｃｅｔａｌｓ[4].Ａｃｃｏｒｄｉｎｇｔｏｔｈｅｐｒｅｖｉ ｏｕｓｒｅｐｏｒｔ,ｔｈｅｏｘｉｄ…     

Synthesis and Crystal Structure of Tert-butyl 4-[(E)-4-(1,3-Dioxo-1,3-dihydro-2H-isoindol-2-yl)-1-butenyl] Benzoate

1 INTRODUCTION Phthalimide and its derivatives are synthetic mate- rials, which are widely used as important chemical intermediates of biosensors[1] and many drugs such as Citalopran[2], luminal[3], Beta-Lactam[4] and the No. three generation quinolones[5], and they have been identified as active groups of some drugs and chemical luminescence reagents[6, 7]. Tert-butyl 4- [(E)-4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-1- butenyl] benzoate is an intermediate of a new type of insulin sen…     

Crystal and Molecular Structure of 2-(2, 6-Dinitro-4-Trifluoromethyl) phenylthio-5, 7-Dimethyl-1,2,4-Triazolo [1, 5-a] Pyrimidine

1INTRoDUCTIONItwasreportedthattheheterocycliccompoundscontainingl,2,4-triazolo[1,5-ajpyrimldinyldisplayedpotentialbioIogicalactivities['2i.Howeverltheherbicidalac-tivityofthethio-etherderivativesof1,2,4xtriazolo[1,5-ajpyrimidinewasrarelyre-ported"'.Inourpreviouspaper"',wedesignedandsynthesizedaseriesof2-arylthio-l,2,4-triazolo{l,5-ajpyrimidines,someofwhichdisplayedgoodherbicidalactivity.Inordertostudythestructure-activityrelationshipofthesecompounds,thestructureofthetitlecompound(1)wasan…     

One-dimensional Zigzag Chain Composed of HgI2 Unit and 2,5-Bis（4-pyridyl）- 1,3,4-thiadiazole： [HgI2（C12H8N4S）]

1 INTRODUCTION Much interest has been focused on the design and syntheses of supramolecular coordination polymers with novel topologies and structural motifs because of their encouraging potential applications in the fields of nonlinear optics, catalysis and separation, magnetism and molecular recognition[1, 2]. In princi- ple, control over the type and topology of the coor- dination polymers can be achieved by careful choice of ligand, metal coordination geometry preference, inorganic cou…     

Synthesis and Crystal Structure Analysis of 4-Dibenzaldehydeamino-4H-1,2,4-triazole Diacetate

The new title compound 4-dibenzaldehydeamino-4H-1,2,4-triazole diacetate （C16H18N8O4,Mr = 386.38） has been prepared and its crystal structure was determined by single- crystal X-ray diffraction. The crystal is of monoclinic,space group P21/n with a = 8.1371（17）,b = 7.1237（12）,c = 16.325 （2）A,β = 100.366（2）°,V = 930.9（3） A^3,Z = 2,Dc = 1.378,F（000） = 404,μ = 0.104 mm^-1,MoKa radiation （λ = 0.71073 ）,R = 0.0307 and wR = 0.1196 for 4632 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals that the molecule is not flat and the crystal structure is stabilized mainly by van der Waals interactions.     

Synthesis and Crystal Structure of 2-Morpholinylthioformyl-2-phenyl-4-morpholinyl-5-phenyl-1,3-dithiole

1　ＩＮＴＲＯＤＵＣＴＩＯＮα Ｔｈｉｏｃａｒｂｏｎｙｌｔｈｉｏｆｏｒｍａｍｉｄｅｓｗｅｒｅｓｙｎｔｈｅｓｉｚｅｄｉｎ 1 980 [1～ 2 ],ｈｏｗｅｖｅｒ,ｔｈｅｒｅｗａｓｎｏｒｅｐｏｒｔｏｎｔｈｅｉｒｐｒｏｐｅｒｔｉｅｓａｎｄｒｅａｃｔｉｏｎａｃｔｉｖｉｔｉｅｓ[3].Ｗｅｒｅｐｏｒｔｅｄｔｈｅｒｅａｃｔｉｏｎｏｆα ｔｈｉｏｃａｒｂｏｎｙｌｔｈｉｏｆｏｒｍａｍｉｄｅｓｐｒｅｖｉｏｕｓｌｙ[4 ].Ｈｅｒｅ ,ｗｅｒｅｐｏｒｔｔｈｅｓｙｎｔｈｅｓｉｓｏｆ 2 ｍｏｒｐｈｏｌｉｎｙｌｔｈｉｏｆｏｒｍｙｌ 2 ｐｈｅｎｙ…