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1.
1INTRODUCTION The chemistry of molybdenum-sulfur compounds has attracted the attention from chemists,bioinor-ganic chemists and biochemists because Mo and S are important elements of metal enzymes especially N2-ase[1~6].Since the di-molybdenum(0)thiolate com-pound with a[Mo2S2]2?unit core and two-electron transfer character,[Et4N]2[Mo2(SR)2(CO)8](R=Ph,tBu),was synthesized by introducing thiolate ligands into Mo(CO)6[7],the chemistry of complexes conta-ining low valence molybdenum at…  相似文献   

2.
(NH3CH2CH2NH2)3[Mo(Ⅴ)O2(O2C6H4)2] (1), (NH3CH2CH2NH2)2.5[Mo(Ⅴ)o.sW(Ⅵ)o.502(O2C6H4)2] (2) and(NH3CH2CH2NH2)2[VC(Ⅵ)O2(O2C6H4)2] (3) were synthesized, structurally characterized by X-ray diffraction analysis, and studied on their interactions with ATP, their DNA cleavage activities and antitumor properties. The redox state of molybdenum was not changed on going from crystal to aqueous solutions in complexes 1 and 2, while tungsten underwent reduction from W(VI) to W(V) in complexes 2 and 3. ATP promoted the oxidation of both molybdenum and tungsten from M(Ⅴ) to M(Ⅵ) and the hydrolysis of catecholate ligands in solution consisting of ATP and the complexes. Complex 1 possesses fairly good activity to DNA cleavage and against tumor S180 in mice, and is more effective than the control drug cyclophosphamide under the identical conditions. However, complexes 2 and 3 exhibited marginal effectiveness. The effectiveness of anti-tumor of the complexes was related positively to their DNA cleavage activities and their hydrolysis of catecholate ligands.  相似文献   

3.
The title compound tetraethylammonium hexacarbonylbis(μ-pyridine-2-thiolato-S∶S) dimolybdenum [Et4N]2[Mo2(CO)6(pys)2] crystallizes in the monoclinic, space group, P21/c with a=13.217(2), b=21.648(2), c=27.193(6)(), β=82.52(2)°, V=7714.6()3, Z=8, Mr=840.77, Dc=1.45 g/cm3, μ=7.8 cm-1, R=0.038 and Rw=0.040 for 6082 reflections with I≥3σ(I). X-ray crystal structure study reveals that the asymmetric unit of the title compound is comprised of two independent formulations of the molecular formula. Each dianion has approximate C2 symmetry and the dimetallic Mo2S2 core adopts a "butterfly" conformation with a dihedral angle between the halves of 139.3(1)° for the first independent anion and 142.8(1)° for the second one. The two pyridine rings lie on the same side of the molecule in a cis arrangement and the Mo...Mo separations are 3.76(1) and 3.838(1)().  相似文献   

4.
1 INTRODUCTION Polythiotungstate complexes can be prepared from the protonation of one sulfur atom of [WS4]2- and subsequent intramolecular redox reactions[1,2]. For example, [(S)2W(m-S)2W(m-S)2W(S)2]2 was formed by the acidification of a diluted aqueous solution of (NH4)2[WS4] with dilute H2SO4[3]. When a diluted aqueous solution containing [WS4]2 was acidified with 0.1mol/L HCl, [(S)2W(m-S)2(O)- W(H2O)(m-S)2W(S)2]2 was formed[4]. [(S)2W- (m-S)2(S)W(m-S)2W(S)2]2 was form…  相似文献   

5.
Cis-dioxo-metal complex ( NH3CH2CH2NH2 ) 2.5 [ Mo0.5^(V)W0.5^(VI)O2 ( OC6H4O ) 2] 1 was obtained by the reaction of tetra-butyl ammonium hexamolybdotungstate with 1, 2-dihydroxybenzene in the mixed solvent of CH3OH, CH3CN and ethylenediamine,and characterized by X-ray diffraction, UV-vis and EPR analysis. Compared with its analogous complexes (NH3CH2CH2NH2)3[Mo^(V)O2(OC6H40)2] 2 and (NH3CH2CH2NH2)2[W^(VI)O2(OC6H4O)2] 3, the results show that tungsten(VI) is less active in redox than molybdenum (VI) and that the change of the valence induced by substitution of W(VI) for Mo(V) in EMO2(OC6H40)2]n- does not influence the coordination geometry of the complex anion in which the metal center exhibits distorted octahedral coordination with cis-dioxo catechol. The responses to EPR of complexes 1 and 2 are active but complex 3 is silent,and the UV-vis spectra exhibited by the three complexes are obvious different because of the different electronic configuration between the central Mo(V) and W(VI) ions in the complexes.It is noteworthy that complexes 1 and 2 have the similar EPR signal to flavoenzyme, suggesting that the three complexes have the same coordination geometry feature with the co-factor of flavoenzyme.  相似文献   

6.
The reaction of molybdenum hexacarbonyl with C6H5CH2OC6H4ONa and Et4NBr in CH3CN at 60 ℃ afforded the di-nuclear Mo(0) compound [Et4N]3[Mo2(CO)6(μ-OC6H4OCH2- C6H5)3] 1. 1 crystallizes in monoclinic, space group P21/c with a = 15.359(2), b = 18.378(3), c = 24.952(2), β = 102.268(4)°, V = 6882.3(16) 3, Mr = 1348.34, Z = 4, Dc = 1.301 g/cm3, F(000) = 2832 and μ = 0.424 mm-1. The final R = 0.0606 and wR = 0.1552 for 9396 observed reflections (I > 2σ(I)). 1 contains a [Mo2O3]3- core in triangular bi-pyramidal configuration and each Mo atom adopts a distorted octahedral geometry with three carbon atoms from carbonyls and three μ-O atoms from C6H5CH2OC6H4O- bridging ligands. The Mo…Mo distance is 3.30(8) , indicating no metal- metal bonding. A formation pathway via forming a di-molybdenum(0) di-bridging OR compound [Mo2(μ-OR)2(CO)8]2- has been figured out and the reaction of Mo(CO)6 with alkoxide has also been discussed.  相似文献   

7.
Cis-dioxo-catecholatotungsten(VI) complex anion[W^(VI)O2-(OC6H4O)2]^2- was obtained with discrete protonated ethylenediamine (NH2CH2CH2NH3)^ cations by the reaction of tetrabutyl ammonium decatungstate with catechol in the mixed solvent of CH3OH,CH3CN and ethylenediamine,and compared with its molybdenum anaogue [Mo^(V) O2(OC6H4O)2]^3- by crystal structure,UV,EPR,The results of the UV and EPR spectra show that tungsten is less redox active than molybdenum since the molybdenum is reduced from Mo(VI) to Mo(V) but tungsten stays in the original highest oxidized state Mo(VI) when they are crystallized from the solution above.It is worthy to note that [W^(VI)O2(OC6H4O)]^2- shows the same coordination structure as its molybdenum analogue in which the metal center exhibits distorted octahedral coordination geometry with two cis-dioxocatecholate ligands and might have the related coordination structure feature with the cofactor of flavoenzyme because [Mo^(V)O2(OC6H4O)2]^3- presented essentially the same EPR spectra as flavoenzyme.The NMR studies on the interaction of the title complex with ATP reveal that the reduction of W(VI) to W(V) occurs when the title complex is dissolved in D2O and the W(V) is oxidized again when ATP solution is mixed with original solution and the hydrolysis of the catecholato ligand take places at mean time being monitored by ^1H NMR and ^13C NMR spectra.  相似文献   

8.
Reaction of [Mo3(CO)7(S,O-C6H4-1,2)3]2- with FeCl2 in MeCN at 60℃ affords a new Mo-Fe-S cluster complex containing MoO3S3 unit and mixed-valeut Mo atoms, [Et4N]2[Mo2Fe-(CO)4(O,S-C6H4-1,2)aCl2] (1). 1 is characterized by elemental analysis, IR, Mossbauer spectra, X-ray photoelectron spectra and mass spectra. And the structure of 1 is suggested as the structure which contains a [Mo(S,O-C6H4-1,2)3] unit of which the two of three sulfur atoms link to a Mo(CO)4-moiety and the three oxygen atoms are coordinated to a FeCl2 ligand.  相似文献   

9.
1 INTRODUCTION There has been great and considerable interest in the study of copper nitrite complexes because they are relevant to the study of copper-containing enzymes involved in the denitrification process[1]; in particular, copper-nitrite complexes are potentially relevant to the nitrite reductases[2] (the enzyme from Achromobacter Cycloclastes) which convert NO2- to NO and/or N2O. Many attempts have been made to synthesize a variety of copper-nitrite complexes, in which the n…  相似文献   

10.
周嘉  王宏根 《结构化学》1999,18(2):98-102
The crystal structure of the title compound cis-2-[(P, P-Diethoxy)phosphono(m-nitro)benzyloxy]-4-Phenyl-5,5-Dimethyl-1,3,2-Dioxaphosphorinane 2-Sulfide, C22H29NO8P2S, was determined by single crystal X-ray diffraction. It crystallizes in the monoclinic system, space group P21/c, with Mr=529.49, a=9.888(2), b=20.831(4), c=12.797(3) , β=94.42(3)°, V=2628(1) 3, Z=4, Dx=1.338 g/cm3, λ=0.71073, μ=0.2796 mm-1 and F(000)=556. The structure was solved by direct methods. The final R factor is 0.052 and Rw is 0.057 for 1793 unique observed reflections [I≥3σ(I)]. A cis-configuration and a preferred chair conformation for the molecule have been established by X-ray diffraction analysis. The results presented also give a good explanation to the correlation between the configurational assignments and the regularity in the chemical shifts of C4-H and 31P NMR.  相似文献   

11.
Reaction of Mo(CO)6 with p-H3CO-C6H4SNa and Et4NCl · H2O in CH3CN afforded a dinuclear molybdenum(0) compound [Et4N]2[Mo2 (CO)8 (SC6H4-OCH3-p)2] (1). The crystal structure was determined by X-ray diffraction. The crystallographic data: C38H54Mo2N2O10S2, Mr = 954.87, triclinic, P-1, a = 11.348 (7), b =11.616(5), c=10.065(7) A, a=113.86(4), β=111.39(5), γ=91.92(5)°, V=1104.0(1) A3, Z=1, Dc=1.44 g/cm3, F(000)=492, μ=7.0cm-1, Final R=0. 046 and Rw=0. 049 for 2657 reflections with I>3. Oσ(I). The X-ray structure analysis revealed that the Mo2S2 core of 1 is planar. The geometry around each Mo atom is a distorted octahedron, the two octahedrons form an edge-sharing bioctahedron. The bond. In addition, the 95Mo NMR chemical shift of 1 is discussed.  相似文献   

12.
Reaction of Mo (CO)6 with p-Cl-C6H4SNa and Et4NCl · H2O in CH3CN afforded a dinuclear molybdenum (0) compound [Et4N]2 [Mo2 (CO)8 (SC6H4-Cl-p)2] (1). The crystal structure was determined by X-ray diffraction. The crystallographic data: C36H48Cl2Mo2N2O8S2, Mr= 963.71, monoclinie, P21/c, a=9. 269(4),b=13.750(3), c=17.466(6) A ;β=104.84(3)°; V=2151.8(3) A3; Z=2; Dc=1.49 g/cm3; F(000)=984; μ=8.3 cm-1; MoKα radiation (λ=0. 71073A ); Final R = 0. 055 and Rw=0. 065 for 3287 reflections with I>3. 0σ(I). The X-ray structure analysis revealed that the Mo2S2 core is planar. The geometry around each Mo atom is a distance is 4. 014(2) A , and this obviously indicates the absence of Mo-Mo bond.  相似文献   

13.
1 INTRODUCTIONSincethiolateligandwasintroducedintomolybdenumcarbonylcompoundin1 984 [1],theinvestigationonlow valenceMo -SRcompoundshasreceivedattentionforthiskindoflow valencecompoundspossesscertainadvantageoncompoundsyn thesis,moleculestructureandphysicala…  相似文献   

14.
1 INTRODUCTION The chemistry of complexes containing low-valence molybdenum and tungsten metal atoms hasincreasingly attracted the attention from chemistsand bioinorganic chemists due to their significancefor studying metal enzymes[1~5]. Since the s…  相似文献   

15.
<正> [Me4N]6[Ag6(i-mnt)6].H2O(1),[Et4N]4[Cu8(i-mnt)6](2) and [Me4N]4-[Cu5Ag3(i-mnt)6].H2O(3)(i-mnt=S2C=C(CN)2) were synthesized. The crystal and molecular structure of the complex 1 was reported by us.The structure of the complex 2 was determined from single crystal X-ray diffraction data. [Et4N]4[Cu8(i-mnt)s] 2, Mr=1870.46, monoclinic, P21/n, a=14.724(6), b = 17.228(3), c=15.59(1)A,β= 100.75(7)°,V=3886.3A3;Z = 2,Dc= 1.598 g/cm3. Complex 3 has been characterized by ICP elemental analyses and IR spectrum.  相似文献   

16.
<正> The title compounds were prepared from the reation of (NH4)2MS4 (M=W,Mo),AgNO3,NadtcEt2 and Et4NBr in CH3CN-H2O solution. The isomorphous compounds [Bu4N]2[W2Ag3S8Et2du] ( I ) and [Bu4N]2[Mo2Ag3S8Et2dtc] (Ⅱ) crystallize in triclinic space qroup Pi with the following crystal parameters:α=13. 043(4),b = 21. 640(6),c=10. 757(6)A ,α=95. 09(5),β = 91. 90(4),γ = 98. 57(3)°,Z = 2,V = 2987A3,Dc=1. 76g/cm3 for I 5;a= 12. 989(2) ,b=21. 574 (9) ,c= 10. 7/1(1) A .α= 95. 06(7), β=91. 61(4), γ=98. 52(2)°, Z = 2,V = 2961 A3.Dc= 1. 58g/cm3 for Ⅱ . The final R and Rw values are 0. 061 and 0. 072 for Ⅰ ,and 0. 062 and 0. 076 for Ⅱ The M2Ag3 (M = W, Mo) unit in anion M2Ag3S8Et2dtc forms a five-membered ring.  相似文献   

17.
1INTRODUCTIONTheexistenceandsignificanceofthemolybdenum sulfurbondinginmolybdenumenzymes〔1〕havestimulatedthestudiesonthechemi...  相似文献   

18.
1INTR0DUCTI0NLowva1encemolybdenum/tungstencomp1exeswiththiolatoligandsareusefulforthestudiesonsyntheticandstructuralchemistry.Inrecentyearswehavesynthe-sizedandcharacterizedaseriesofdinuclearMo-SRc0mpoundscontainingaplanarMoSzMocorewithamon0dentatethiolatoligand"-"anda"butterfly"M0S2Mocorewithabidentatethi0latoligand"=."H0wdoesmultidentateliganddo"hasnaturallyattracted0urinterest-2-mercaptoPyrimidine(PymS)wasusedasamultidentateligandtocarry0utsynthesisexperiment.unexpectedly,whichgavea…  相似文献   

19.
<正> [(C2H5)4N]2[Mo2o2S2(S2)2], Mr = 676. 74, monoclinic, P21/c, a = 13.510(2), b = 14.373(2), c=14. 777(3)(?), β = 97.53(2)°, V = 2844.7(9) (?)3, Z = 4, Dc= 1. 58g/cm3, μ(MoKα) = 13.0cm-1, F(000) = 1384, R =0. 033 for 1803 observed reflections. The structure contains discrete [Mo2O2S2(S2)2]2- anions and Et4N+ cations. The two oxygen atoms bonded to the Mo atoms are in cis-form with respect to the Mo2S2 bridging unit, with an average Mo- O distance of 1. 678 (?), The Mo…Mo distance is 2. 832(1)(?).  相似文献   

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