Structure design and property adjustment of new cage rich-nitrogen pentazolyltetraazacubanes as potential high energy density compounds

In this study,based on two attractive energetic compounds pentazole(PZ) and tetraazacubane(TAC),a new family of high energy and high nitrogen compounds pentazolyltetraazacubanes were designed.Then,a different number of NH2 or NO2 groups were introduced into the system to further adjust the property.The structures,properties,and the structure-property relationship of designed molecules were investigated theoretically.The results showed that all nine designed compounds have extremely high heat of formation(HOF,1226-2734 kJ/mol),good density(1,73-1.88 g/cm3),high detonation velocity(8.30-9.35 km/s),high detonation pressure(29.8-39.7 GPa) and acceptable sensitivity(△V:41-87 A3).These properties could be effectively positive adjusted by replacing one or two PZ rings by NH2 or/and NO2 groups,especially for the energy and sensitivity performance,which were increased and decreased obviously,respectively.As a result,two designed pentazolyltetraazacubanes were predicted to have higher energy and lower sensitivity than the famous high energy compound in use 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane,while two others have better co mbination property than 1,3,5-Trinitro-1,3,5-triazacyclohexane.In all,four new pentazolyltetraazacubanes with good combination performance were successfully designed by combining PZ with TAC,and the further property adjustment strategy of introducing a suitable amount of NH2/NO2 groups into the system.This work may help develop new cage energetic compounds.

Synthesis and Crystal Structure of a New [Mn_2Ni_2] Cubane Complex

A new Mn2Ni2 cubane complex has been synthesized and characterized by single-crystal X-ray diffraction,FT IR spectra and elemental analysis.The title compound [MnIII2NiII2（hmp）4（N3）4（O2CR）2]（hmp-is the anion of 2-pyridinemethanol and O2CR-is α-na-phthaleneacetate）crystallizes in the monoclinic system,space group P21/c with a = 10.519（5）,b = 22.109（10）,c = 23.235（9）,β = 106.096（17）o,C48H42Mn2N16Ni2O8,Mr = 1198.28,V = 5192（4）3,Dc = 1.533 g/cm3,F（000）= 2448,μ = 1.258 cm1,Z = 4,the final R = 0.0875 and wR = 0.2020 for 3398 reflections with I 2σ（I）.X-ray diffraction analysis reveals that each Mn（III）center is octahedrally coordinated by two nitrogen atoms of azide anions and three oxygen atoms from three 2-pyridinemethanol anion ligands together with one oxygen atom from naphthaleneacetate.Each Ni（II）is octahedrally coordinated by two nitrogen atoms of 2-pyridinemethanol anion ligands as well as three oxygen atoms from three 2-pyridinemethanol anion ligands and one oxygen atom from naphthaleneacetate.

SYNTHESIS, STRUCTURE AND ELECTROCHEMICAL STUDIES ON SINGLE MoFe_3S_4 AND WFe_3S_4 CUBANE-TYPE CLUSTER COMPOUNDS*

Single cubane-like clusters, MFe3S4（R2dtc）5 （M=Mo, R2=—（CH2）4—, Bz2; M=W, R2=Me2, —（CH2）4—; dtc=dialkyldithiocarbamate） were synthesized by assembly reaction of （NH4）2MS4 （M=Mo, W）, FeCl2 with R2dtcNa （or NH4） in DMF. The structure, IR, EPR and cyclic voltammogram are described and discussed. MoFe3S4（C4H8dtc）5 was also obtained from the conversion of linear cluster Fe（DMF）6[（FeCl2）2MoS4] in the presence of C4H8dtc NH4. Both clusters MoFe3S4（C4H8dtc）4·2C2H5CN and WFe3S4（C4H8dtc）5·2DMF crystallize in the monoclinic space group C2/c with a=12.544（2）, （Mo-cluster）, 12.533（4） （W-cluster）; b=20.478（4）, 20.121（6）; c=19.582（7）, 19.659（2）;β=102.82（2）, 102.96（3）°; and Z=4, 4. Their structures were refined to R=0.057 and 0.064 with use of 2690 and 2179 reflections （ι】3Q（I））, respectively. Many similarities in structure for Mo and W clusters indicate that both Mo and W play a very similar role in the clusters.

SINGLE Mo_(n)Fe_(4-n)S_(4) (n=0, 1, 2) CUBANE-LIKE CLUSTERS: PREPARATION FROM COMBI-NATION OF DINUCLEAR COMPLEXES AND THE STRUCTUREOF [Mo_(2)Fe_(2)S_(4)(C_(4)H_(8)dtc)_(6)]·3.5C_(2)H_(2)Cl_(4)

Three types of unit combinations, FeS2Fe + FeS2Fe, FeS2Fe + MoS2Fe and MoS2Mo + MoS2Mo, lead to Fe4S4, MoFe3S4 and Mo2Fe2S4 cubane-like clusters, respectively. A new doubly bridged single cubane cluster [Mo2Fe2S4(C4H8dtc)6]·3.5C2H2Cl4 has been obtained and its structure is discussed.

The First Homochiral Diamond-Like Coordination Polymer Containing Cubane Cluster （Cu4I4） as Connecting Node and Cinchonine as Donor-Acceptor （or Push-Pull Electronic Effect） Building Block

The reaction of CuI with cinchonine （an organic donor-acceptor chromophore） afforded a homochiral 3D diamondoid network [Cu4I4（cinchonine）2]n （1） containing a cubane cluster （Cu4I4） as a connecting node. This is the first homochiral coordination polymer with diamondoid nets containing a cluster as a connecting note. Its thermal stability and solid state optical properties such as fluorescence, circular dichroism and second-harmonic generation response were also reported.

Synthesis and structure of a novel MoFe_4S_4 cubane-like cluster (Me_3PhCH_2N)_2[MoFe_4S_4(SC_6H_(11))_7]

A novel (Me 3PhCH 2N) 2[MoFe 4S 4(SC 6H 11 ) 7] cubane like cluster was obtained from a reaction system including (NH 4) 2MoS 4, FeCl 2 and NaSC 6H 11 in methanol, and characterized by X ray crystallography. The title compound crystallizes in triclinic space group P 1 with a =1.523 1(3), b =1.610 5(3), c =1.838 3(4) nm, α =77.18 (3)°, β =75.17(3)°, γ =64.60 (3)°, and Z =2. Also included in this paper are the discussions on the variation of the reaction products obtained from the participation of cyclohexylthiolate and on the changes of the structural features of the products.

Synthesis and Crystal Structure of a Tetranuclear Cubane-like Nickel（Ⅱ） Complex with 2-Hydroxymethyl-N-salicylideneaniline

The tetranuclear cubane-like complex, [NiL（EtOH）]4·0.5EtOH （1） with tridentate Schiff base ligand （H2L= 2-Hydroxymethyl-N-salicylideneaniline） has been synthesized and its crystal structure and spectroscopic properties have been studied. The complex consists of a tetranuclear （NiO）4 cubane core, of which four nickel（Ⅱ） ions are bridged by μ3-alkoxide group and each nickel（Ⅱ） ion is coordinated to three μ3-alkoxide oxygen atoms, one imino nitrogen atom and one phenoxide oxygen atom from Schiff base ligand, and further ligated by one EtOH molecule, completing a distorted octahedral geometry.

The Revolution’s Result: The Change of Cuban-American Relations During the 1959-1962 Period

Cuban-American relations have become one of the most attractive bilateral relations since the Cold War era.With historical methods and international relations theory,this paper aims to discuss the Cuban Revolution and the change of Cuban-American relations through two issues.One is the Cuban Revolution and the gradual rupture of traditional Cuban-American ties,demonstrating that since Castro’s radical reform of nationalization deeply violated the economic interests of the United States,conflicts and confrontations had already been incurred.At the same time,with Moscow’s intervention,the Cuban Revolution gradually became complicated and sensitive to deal with from Washington’s perspective.The other one is the evolution of confrontation between the Castro revolutionary regime and the United States government during the 1959-1962 period.The Bay of Pigs Invasion rapidly caused political tensions in Cuban-American relations,and soon,the Cuban Missile Crisis institutionalized the escalating confrontation and deeply worsened bilateral relations.As a result,the Castro regime had no choice but to rely on Soviet assistance to maintain a delicate balance with the United States for several decades,which indicated the tragedy of the small nations’destiny.

古巴蝇人工繁殖技术及其对二点螟的寄生能力(英文)

[Objective] The artificial breeding technology of Cuban fly （Lixophaga diatraeae） and its parasitic ability on Chilo infuscatellus was studied.[Method] Through artificial inoculation experiment,the effects of different inoculation proportions between maggot and Galleria mellonella larvae on the growth and development of Cuban fly were studied.Through indoor low temperature storage tests,effects of different temperatures on the emergence rate of Cuban fly were studied;and the effects of different ecological conditions （humidity,sunshine） on the emergence rate of Cuban fly and its parasitic ability on Chilo infuscatellus were studied through indoor and field comparison experiment.[Result] The optimum inoculation proportions between maggot and G.mellonella larvae were 3：1 and 4：1,pupa production amounts were 279 and 327,respectively;short storage under the temperature of 10℃ had small effect on the emergence rate of Cuban fly,while the storage time should not exceed 15 d.Indoor and field parasitic test showed that Cuban fly had strong parasitic ability on C.infuscatellus,the parasitic rate reached 33.3%-50.0%;the parasitic rates during elongation stage and maturation stage were 47.8% and 41.7%,respectively,while they almost could not parasite during seedling stage.[Conclusion] The results provided scientific basis for artificial breeding of Cuban fly in large scale and its field release technology.

Synthesis and Structure of [Er_4(μ_3-OH)_4(Hpro)_4(pro)_2(H_2O)_7](ClO_4)_6·7H_2O

The title compound [Er4(m3-OH)4(Hpro)4(pro)2(H2O)7](ClO4)67H2O has been synthesized and its crystal structure was determined by X-ray diffraction study. It crystallizes in rhombohedral, space group R3, a = b = c = 12.7812(2) ? a = b = g = 100.067(1), V = 1978.19(5) 3, Z = 1, Mr = 2274.77, Dc = 1.909 g/cm3, F(000) = 1112, m = 4.506mm-1, the final R = 0.0405 and wR = 0.1068 for 3711 observed reflections (I > 2s(I)). Four Er3+ ions and four m3-OH display a Er4O4 cubane structural motif. Each proline interconnects two Er3+ ions.

Ex vivo antioxidant effects of D-004, a lipid extract from Roystonea regia fruits, on rat prostate tissue

Aim： To investigate whether oral treatment with D-004, a lipid extract of the Cuban royal palm fruit, produces antioxidant effects in the prostate tissue of normal and testosterone （T）-treated rats. Methods： In our first experiment, normal rats were distributed into five groups： one group treated with the vehicle and four groups treated with D-004 （100, 200, 400 or 800 mg/kg）. In our second experiment, rats were randomized into five groups： a negative control group and four T-injected groups. The latter were comprised of a positive control group treated with the vehicle, and three groups treated with D-004 （200, 400 or 800 mg/kg）. Results： In normal rats, D-004 （100-800 mg/kg） inhibited significantly and dose-dependently iron-initiated malondialdehyde （MDA） accumulation in prostate homogenates （35.7%-80.0%） vs. the controls. D-004 （200-800 mg/kg） significantly reduced baseline MDA and carbonyl groups in prostate homogenates of normal rats to approximately 80% and 50%, respectively, and totally （100%） in T-treated rats. Conclusion： Oral treatment with D-004 reduced MDA and carbonyl groups dose-dependently and markedly in normal and T-injected rats. These findings show that D-004 given at doses effective to prevent prostate hyperplasia also produces antioxidant effects in the prostate tissue.

The Role of Human Herpesvirus 8 Molecular Characterization in the Management of HIV Infected Patients Diagnosed with Malignancies Associated with Its Infection

Despite the progress has been reached with Human herpesvirus 8 (HHV-8) research, there are gaps in the knowledge of viral induced oncogenesis. The aim of the present study was to identify possible associations between HHV-8 subtypes, HHV-8 loads and clinical manifestations of HIV infected patients diagnosed with different malignancies associated with HHV-8 infection. Forty six HIV-1 infected individuals diagnosed with different HHV-8 associated diseases were studied [37 epidemic Kaposi’s sarcoma (KS), 3 pleural effusion lymphoma (PEL);5 peripheral lymphadenopathies (PL);1 Hodgkin’s lymphoma (HL);1 non Hodgkin’s lymphoma (NHL)]. HHV-8 loads were determined by quantitative real time PCR (qRT-PCR) whilst HHV-8 subtypes were determined by open-reading frame (ORF)-K1 gen genotyping. HHV-8 subtypes B, A, C, A5 and E were exhibited by 31.8%, 23.4%, 19.1%, 17% and 8.5% of the studied patients, respectively. The median HHV-8 viral load did not differ between subtypes (p > 0.05) but HHV-8 viral loads were significantly higher in PEL than in epidemic KS lesion or lymph nodes (p = 0.04). Subtype B was detected in 60% of patients with B cell lymphoma (NHL, PEL and HL) whereas subtype E was only detected in patients with epidemic KS diagnosis. Our data suggest that HHV-8 DNA quantification instead of subtype identification could be used as a surrogate marker for monitoring its infection, not only in epidemic KS patients but also in HIV infected individuals with lymphoproliferative disorders.

Synthesis and Characterization of Novel μ-Carbonato Tetranuclear Copper Complexes [(Pip)4nCu4X4(CO3)2] in Aprotic Media

In this work, novel oxidative coupling complexes, [(Pip)4nCu4X4(CO3)2] (n = 1 or 2, X = Cl or Br, Pip = piperidine), are synthesized from the reaction of well characterized Lewis base [(Pip)4nCu4X4O2] with carbon dioxide as a Lewis acid in CH2Cl2. These carbonato-derivatives are isolated as stable solids. They are easily soluble in aprotic solvents as CH2Cl2or phNO2. Cryoscopic measurements support tetranuclear structure for all of them. Electronic spectra in the near infrared with high molecular absorptivity may be explained for tetranuclear cuban structure to fulfil 3 halo-ligands for each copper centre in [(Pip)4nCu4X4(CO3)2]. The EPR spectra for [(Pip)4nCu4X4(CO3)2] complexes are axial type of spectra (dx2-y2 G.S) suggesting elongated tetragonal distortion for all of them. Cyclic voltammograms for [(Pip)4nCu4X4(CO3)2] are irreversible in character. These tetranuclear carbonato complexes show catalytical activity. They initiate the oxidation of 2,6-dimethylphenol (DMP) to 3,3’,5,5’-tetramethyl-4,4’-diphenoquinone (DPQ).

Syntheses of heterometallic V/Cu/S clusters and structural characterization of (Et_4N)_2[V_2Cu_2S_4(C_5H_(10)dtc)_2]

Three kinds of complexes,V2Cu2S4 cubane-like,VS4Cu4 planar and V3S7 triangular dusters areobtained from a reaction system composed of（NH4）3VS4,CuCl,R2dtcNa and PhSNa.A mechanism of theformation of the products is suggested.The title compound is structurally characterized,showing the metaloxidation states of V（IV）+Cu（I）.Also discussed are IR,UV-Vis and NMR spectra,and cyclic voltagrammetryfor the V2Cu2S4 clusters.

A little-known history of 170 years of struggle by Cuban Chinese

In June,at Havana Jose Marty International Airport,enclosed with red walls,Caridad Diego,a member of the Cuban Communist Party Central Committee and president of the Cuba-China Friendship Association,welcomed the delegation led by Ma Peihua,vice-chairman of the Chinese People’s Political Consultative Conference and president of the China-Latin America and