EPR STUDY ON THE ELECTRON TRANSFER OF IRON COMPLEXES WITH MO_XS_(4_X)~2 (M = Mo,W;x=0 -2) LIGANDS

<正> In recent years, the chemistry of high-valent molybdenum compounds containing sulfur has gained momentum, probably due to its importance in various metallo-biomolecules which are responsible for vital functions like electron transfer and redox reactions. The relevance of thiomolybdates, MoO_xS_(4-x) ~(2-)(x=1—2),and particularly of MoS_4~(2-) to biologi     

Synthesis, Crystal Structure and Biological Activities of N′-(4-Methoxybenzylidene)-2-(1H-1,2,4-triazol-1-yl)acetohydrazide

IntroductionBoth triazole derivatives and Schiff base are repor-ted to possess significant antifungal and plant-growthregulatory activities[1—6].Further,triazole drugs are al-so very common in the medical field.These give a greatimpetus to the research for potential pharmacologicallyactive Schiff base containing triazole.In order to search for newtriazole compounds withhigher biological activity,the title compound was syn-thesized and its biological activities were tested.Also,its structure…     

Synthesis of 1-[6-Fluoro-(2S)-3H,4H-dihydro-2H-2-chromenyl]-(1R)-1,2- ethanediol and 1-[6-Fluoro-(2R)-3H,4H-dihydro-2H-2-chromenyl]- (1R)-1,2-ethanediol

Benzopyran compounds possess diverse pharmacological properties such as β-blockade, anticonvulsant and antimicrobial.[1,2] Our interest has been focused on the synthesis of 1-[6-Fluoro-2S]-3H,4H-dihydro-2H-2-chromenyl]-(1R)-1,2-ethanediol (6) and 1-[6-fluoro-(2R)-3H,4H-dihydro-2H-2-chromenyl]-(1R)-1,2-ethanediol (7) which are particularly convenient precursor to (S,R,R,R)-NE (8). 8 containing four asymmetrical carbon atoms was reported to be the most active isomer.[3] Chandrasekhar[4] has reported on the synthesis of 8. The key step to synthesize this compound is to obtain the chiral chromanone 6 and 7. 6 was accomplished in 8 steps by the Clasien rearrangement and a one-pot Sharpless asymmetric epoxidation, but the compound 7 was accomplished in 10 steps. Johannes[5] used Zr-catalytic kinetic resolution of allylic ethers and Mo-catalyzed chromene formation to synthesize 8 in 14 steps. However both of the methods request many synthetic steps and expensive reagents.     

A Corrugated 2D Mn(Ⅱ) Network:[Mn_3(μ-oxalate)_3(μ-4,4'-bpy)_2(4,4'-bpy)_2]_n

1 INTRODUCTION It is well known that the bi-functional 4,4?-bi- pyridine (4,4?-bpy) has the ability to act as a rigid, rod-like organic building block in the self-assembly of coordination frameworks. Many researches have also been done on the metal oxalate compounds. The remarkable coordination abilities of oxalate and 4,4?- bpy ligands are applied to design and synthesize new polymeric coordination complexes[1～4] containing mixed bridging ligands. Manganese is one of the several first-r…     

Reactions of Methyl 1-(Bromoacetyl)azulene-3-carboxylate with 2-Hydroxy-benzaldehydes: Synthesis of 1-(Benzofuran-2-yl)-3- methoxycarbonylazulenes

A few compounds containing the 2-arylbenzofuran nucleus, have been isolated from plants.[1] For example,moracins A and B, egonol, homoegonol and (±)-machicendiol are well known.     

Synthesis and Spectroscopic Properties of Cyclotriphosphazenes Containing 6-(4-Hydroxyphenyl)-2,2''-bipyridine Side Groups

Two novel cyclotriphosphazene derivatives containing 6-(4-hydroxyphenyl)-2,2'-bipyridine(hopbp)side groups,N_3P_3(dobp)_2(hopbp)_2(1)and N_3P_3(dobp)(hopbp)_4(2)(dobp=2,2'-dioxybiphenyl),were synthesized and characterized.These compounds display strong fluorescent emission both in solution and in solid state.Their absorption and emission spectra are sensitive to proton:the addition of HBF4 to the methanol and dichloromethane solution(9∶1,volume ratio)of compound 1 led to a red-shift from 350 to 460 nm for the emission spectrum,and the process was also characterized by isosbestic points of absorption spectra at 267,287 and 313 nm.     

Synthesis and Crystal Structure of Spiro[1-bromo(S)-4-(R)-hydroxy-5-oxa-6-oxo-bicyclo[3.1.0]hexane-2,2''''-(3''''-diethyl-α-(S)-4''''''''-Cl-benzyloxyphosphonyl-4''''-(1R,2S,5R)-menthyloxybutyrolactone)]

1 INTRODUCTION In recent years, phosphorus compounds havebeen playing an important role in the new “high-tech” areas including life science and industrial te-chnology[1, .At the same time, the asymmetric syn- 2]thesis of various natural compounds containing cyc-lopropane components and organophosphorus grouphas attracted much attention due to their special bio-logical functions and antibiological activities[3～5].Despite the great advances in these areas, no novelapproach to the efficien…     

Three New Zn(Ⅱ)/Cd(Ⅱ) Coordination Polymers Constructed with 2-Mercaptonicotinic Acid and 1,2-Di(4-pyridyl)ethylene: Syntheses and Structure Analysis

Three new Zn(Ⅱ)/Cd(Ⅱ) coordination polymers based on 2-mercaptonicotinic acid (H2mna) with 1,2-di(4-pyridyl)ethylene (dpe) introduced as a bridging ligand have been synthesized via hydrothermal method and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis and IR. As reported in this paper, [Zn2(dpe)0.5(mna)2] (1) can be classified as a two-dimensional layer structure in which the 1D chain composed of Zn(Ⅱ) and mna ligands is bridged by dpe ligands, while the complex named [Zn4(dpe)4(mna)4] (2) is a tetra-nuclear cluster compound. These two compounds are further extended to three-dimensional structures by hydrogen bonds along with C-H…π and π…π interactions. Compound 3 with general formular [Cd2(dpe)0.5(mna)2]·H2O belongs to a three-dimensional porous structure in which the 2D metal layers formed by the coordination of Cd(Ⅱ) and mna ligands are connected with the bridging of dpe ligands.     

Thermal Behavior and Decomposition Kinetics of the Complexes of CuX_2 (X=NO_3, Br, Cl and ClO_4) with 3,3''''-Dimethyl-1-(1H-1,2,4-triazol-1-yl)-2-butanone

Introduction N-1-Alkyl-substituted 1,2,4-triazole compounds, like some other heterocyclic derivatives containing nitrogen, have recently been the subjects of numerous studies due to their fungicidal action1 and plant growth regulation.2 Among them, the complexes with a sort of triazole as ligand are of considerable interest because of their broad-spectrum bioactivity, coordination and photo-chemical properties, as well as many potential applica-tions in various fields.3,4 In our previous paper…     

Crystal and Molecular Structure of N—Phenyl 1—Methoxycarbonylmethyl—3—benzyl—1,2,3,4—tetrahydro—4—oxo—1,3,2—benzodiazaphosphorin—2—thiocarboxamide 2—Oxide

1 INTRODUCTIONOrganophosphorus compounds are ubiquitous in nature and they have broad applications in the fields of agriculture and medicine. During the past two decades, (-ketophosphonates and their derivatives containing sulfur have attracted considerable attention because these compounds are endowed with special physical, chemical and pharmacological properties due to the proximity of the carbonyl and the phosphoryl groups[1～8]. In the study on new pharmacenticals and agrochemicals, th…     

Synthesis,halogenation and structural characterization of (Z)-1-[2-(triphenylstannyl)vinyl]-l-cyclododecanol

Synthesis and characterization of (Z)-1-[2-(triphenylstannyl)vinylj-l-cyclododecanol,c-(CH2)11C(OH)CH=CHSnPh3,are reported,together with its halogenation by I2,Br2 and IC1 to yield derivatives of the types c-(CH2)11C(OH)CH=CHSnPh3_nXn (n=1,2; X=I,Br,Cl,respectively).The molecular structures of two compounds have been determined by X-ray diffraction analysis.The tin atom exhibits a distorted tetrahedral geometry in the crystal of (Z)-1-[2-(triphenylstannyl)vinyl]-1-cyclododecanol,but a trigonal bipyramidal geometry in the monoiodo-derivative (Z)-1-[2-(diphenyliodo-stannyl)vinyl]-l-cyclododecanol and other derivatives,in which significant intramolecular coordinative interaction HO→Sn is observed.And the formation of a five-membered tin containing ring is significant for their antitumour activities.     

Synthesis and Crystal Structure of Ni_3(admt)_6(NCS)_6·C_2H_5OH·2H_2O

1　INTRODUCTIONCoordination compounds with 1 ,2 ,4 triazole as a ligand have interesting fea tures,notonly because ofthe very interesting magnetic propertiesofthese complex es,but also because ofrich modes ofcoordination〔1〕.Particularly,the coordinationbehavioroftriazoletowardsa numberoftransition metalthiocyanatesshowsremark abledifferences〔2 - 6〕.On unsubstitution at N4 ,thetriazole ring hasmonodentate,1 ,2 and 2 ,4 bridging forms.These three modes were all observed in the Ni( II)…     

Synthesis of 4-（2-Phenylhydrazono）-l-（4-phenylthiazol-2-yl）- 1H-pyrazol-5（4H）-one Compounds and Characterization of Their Affinities to Anti-apoptotic Bcl-2 Family Proteins

Organic compounds containing the thiazol-2-yl-lH-pyrazol-5（4H）-one moiety are known to be associated with versatile pharmacological applications. In this study, we describe the methods for preparing 4-（2-phenylhydrazono）- l-（4-phenylthiazol-2-yl）-1H-pyrazol-5（4H）-one compounds. A set of 26 compounds were synthesized with overall yields ranging between 37%-92%. They were tested in a fluorescence polarization-based binding assay against three anti-apoptotic Bcl-2 family proteins, including Bcl-xL, Bcl-2, and Mcl-1. Our results indicate that this class of compounds are not effective inhibitors of these anti-apoptotic Bcl-2 family proteins. Their apoptosis-inducing ef- fects are possibly due to BAX activation as suggested by Gavathiotis et al. in their recent study. However, other possibilities should not be ignored. In addition, a crystal structure obtained by us reveals that the exocyclic double bond in the molecular structure of this class of compounds is in the （Z）-configuration.     

Synthesis and Crystal Structure of cis-Bis(3-hydroxy2-ethyl-4-pyranonato)dioxomolybdenum(Ⅵ)

1 INTRODUCTION 3-Hydroxy-2-methyl-4-pyranone (maltol) and 3-hydroxy-2-ethyl-4-pyranone (ethylmaltol) are nontoxic compounds that have been applied to bio- inorganic chemistry over several decades[1, 2]. Their iron(III) complexes are relevant to the control of iron levels in the human body. Such complexes have been assessed for the amelioration of anaemia[3] and their respective ligands have been tested for the removal of excess burdens of iron in diseases such as siderosis, haemochroma…     

Syntheses and Structures of Uwo New Oxalate-bridged Transition-metal Supramolecular Polymers of [M(2-NH_2py)_2(ox)]

Two new supramolecular polymers [M(2-NH_2py)_2(ox)][M=Co(1),Ni(2);2-NH_2py=2-aminopyridine;ox=oxalate] were hydrothermally synthesized and characterized by elemental analyses,IR and single-crystal X-ray diffraction analyses.The isomorphic compounds 1 and 2 both possess one-dimensional zigzag chain structures,which are composed of [M(2-NH_2py)_2]2 units bridged by tetradentate oxalate ligands to form three-dimensional supramolecular network via the C-H…O hydrogen bonds and π-π stacking interactions.Compound 1 displays antiferromagnetic interaction.     

New Synthesis and Molecular Structure of 2-(4'-Methoxyphenyl)-2,4-dithia-1,3,2-diazaphospholidine-5,1'-spirocyclohexane

1 INTRODUCTION Our continuous efforts to look for biologically active heterocyclic compounds led to a new and efficient synthesis of phosphoroheterocycles 1, 3, 2-diazaphospholidine-4-thione 2-sulfides in good yields by the treatment of Lawesson磗 reagent with various -aminonitriles in one-pot procedure. Many approaches to synthesize such phosphoroheterocycles have been reported[1~4]. The common pathways leading to 1, 3, 2-diazaphospho- lidine-4-thione(one) 2-sulfide(oxide) are using t…     

Crystal and Molecular Structure of N-(1-Ethoxycarbonyl- ethyl)1-Ethoxycarbonylmethyl-3-ethyl-1,2,3,4- tetrahydro-4-oxo-1,3,2-benzodiazaphosphorin- 2-carboxamide 2-Oxide

1 INTRODUCTIONOrganophosphorus compounds are ubiquitous in nature and they have broad applications in the fields of agriculture and medicine. During the past two decades, (-ketophosphonates and their derivatives have attracted considerable attention because these compounds are endowed with special physical, chemical and pharmacological properties due to the proximity of the carbonyl and the phosphoryl groups[1～6]. For example, it is well known that phosphonoformic acid (PFA) is effectiv…     

Synthesis and Crystal Structure of 5（R）-（1R,2S,5R）-Menthoxy-4（R）- N-cyclohexylaminobutyrolactone

1INTRODUCTION Substitutedγ-butyrolactones are a group of impor-tant compounds containing unique carbon skeleton of butyrolactone which is widely present in many natural products and have received considerable interest because of their biological and medicinal properties[1～4].Therefore,much attention has been paid to the new asymmetric methods for synthesi-zing these interesting compounds[5～11].The prece-ding results led us to explore the possibility of using cyclohexylamine to convert5(…     

Synthesis, crystal structure and magnetic properties of a novel manganese(II)-nitronyl nitroxide-azido(μ_(1,1) and μ_(1,3)) one-dimensional complex

A novel one-dimensional manganese(Ⅱ) complex containing nitronyl nitroxide radical [Mn2(IM2-py)2(Ac)2((μ1.1-N3)(μ1,3-N3) . EtOH]n was synthesized and characterized structurally and magnetically. It crystallizes in the monoclinic space group p21/n. Each Mn(Ⅱ) ion is six-coordinated in a distorted octahedral environment. The two N atoms of the nitronyl nitroxide radical and the two O atoms of acetate ligands are in the equatorial plane, whereas the two different azido bridging ligands are in trans axial position. Mn(Ⅱ) ions are linked by nitrogen atom of μ1,1-azido and oxygen atoms of two carboxy groups to form a Mn-Mn unit. Mn-Mn units are linked by azido ligands through u1,3 bridging style to form a one-dimensional chain. The compound is connected by the coordination bonds,π-π interactions and hydrogen bonds as a three-dimensional structure. Magnetic susceptibility data support that there are stronger antiferromagnetic interactions between the radical and Mn(Ⅱ) ion, weak antiferromagnetic inter     

BrΦnsted acid-promoted ‘on-water’ C(sp^3)-H functionalization fot the synthesis of isoindolinone/[1,2,4]triazolo[1,5-a]pyrimidine derivatives targeting the SKP2-CKS1 interaction

The isoindolinone and biaryl scaffolds are prevalent in natural products and drug molecules,which have showed broad and interesting biological activities.The efficient construction of such hybridized molecules and biological evaluation are of great interest to medicinal chemistry community.In this communication,we report an efficient BrΦnsted acid-promoted C(sp^3)-H functionalization approach that enables the rapid construction of biologically important isoindolinone/[1,2,4]triazolo[1,5-a]pyrimidine hybrids from 5-methyl-7-(2,4,6-trimethoxyphenyl)-[1,2,4]triazolo[1,5-a]pyrimidine,2-formylbenzoic acid and various anilines.The title compounds were generated in high to excellent yields(up to 96%)regardless of the electronic nature and steric effects of the substituents.In this reaction,an isoindolinone scaffold,one C-C single bond,and two C-N bonds were formed simultaneously with high atom economy.In this work,we have envisioned that the methyl group linked to the electron-deficient Nheterocycles could be used as a new synthetic handle for late-state diversification and may have broad applications in the field of organic and medicinal chemistry.Besides,the title compounds have exhibited promising activity against the SKP2-CKS1 interaction.