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Conclusions A number of new 10-(O,O-dialkylphosphonoformyl) derivatives of phenoxazine and phenothiazine were obtained.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2624–2625, November, 1972.  相似文献   

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Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, p. 2164, September, 1991.  相似文献   

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利用 2 -甲氧羰基乙基三氯化锡与硫代水杨醛缩邻氨基苯酚 (H2 L)进行反应合成了标题配合物 [2 -(2 -羟基苯基 )亚氨甲基苯硫酚根 (2 -) -N,O,S](2 -甲氧羰基乙基 -C,O)氯化锡 CH3OCOCH2 CH2 Sn Cl L(L=2 -SC6 H4 CH NC6 H4 O-2 ) ,该配合物与二甲基亚砜 (DMSO)、六甲基磷酰胺 (HMPA)等单齿配体反应生成混配配合物 CH3OCOCH2 CH2 Sn Cl LL′(L′=DMSO,HMPA) ,与醇 (ROH)反应生成相应的 2 -烷氧羰基乙基锡配合物 ROCOCH2 CH2 Sn Cl L.通过元素分析、红外光谱、核磁共振谱等对配合物的结构进行了表征 .用 X射线单晶衍射测定了标题配合物的晶体结构 ,晶体属三斜晶系 ,P1空间群 ,Z=2 ,晶胞参数 a=0 .870 4(2 )nm,b=0 .93 93 (3 ) nm,c=1 .45 1 1 (3 ) nm,α=98.0 5 (3 )°,β=1 0 3 .0 3 (3 )°,γ=96.99(3 )°.该配合物具有分子内羰基氧原子和配体 L的硫、氮、氧原子对锡原子配位的畸变八面体结构 .  相似文献   

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[reaction: see text] A rational approach to the synthesis of gabosines and other related carba-sugars starting from a masked p-benzoquinone has been designed. The enantioselective acetylation of the hydroxyketal 2 provides a practical entry to either enantiomer of the target products. The strategy has been applied to the synthesis of (+)- and (-)-gabosines N and O and (+)- and (-)-epigabosines N and O. The absolute configuration of natural gabosine O has been established.  相似文献   

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The infrared spectra of the O(2) (-).benzene and O(4) (-).benzene complexes are determined by means of Ar predissociation spectroscopy. Several transitions due to CH stretch fundamentals and various combination bands are observed in the 2700-3100 cm(-1) region. The experimental results are interpreted with the aid of electronic structure calculations. A comparison of the calculated and experimental spectra reveals that the spectrum of O(2) (-).benzene most likely arises from an isomer where the superoxide molecule binds preferentially to one CH group of benzene. In contrast, the spectrum of O(4) (-).benzene yields a CH pattern remarkably similar to that displayed by the C(2nu) X(-).benzene (X=halogen) complexes, consistent with a structure with two CH groups equally involved in the bonding. The lower energy vibrational fundamental transitions of the O(4) (-) anion are recovered with a slight redshift in the O(4) (-).benzene spectrum, establishing that this charge-delocalized dimer ion retains its identity upon complexation.  相似文献   

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Multiple low-lying electronic states of M(3)O(9)(-) and M(3)O(9)(2-) (M = Mo, W) arise from the occupation of the near-degenerate low-lying virtual orbitals in the neutral clusters. We used density functional theory (DFT) and coupled cluster theory (CCSD(T)) with correlation consistent basis sets to study the structures and energetics of the electronic states of these anions. The adiabatic and vertical electron detachment energies (ADEs and VDEs) of the anionic clusters were calculated with 27 exchange-correlation functionals including one local spin density approximation functional, 13 generalized gradient approximation (GGA) functionals, and 13 hybrid GGA functionals, as well as the CCSD(T) method. For M(3)O(9)(-), CCSD(T) and nearly all of the DFT exchange-correlation functionals studied predict the (2)A(1) state arising from the Jahn-Teller distortion due to singly occupying the degenerate e' orbital to be lower in energy than the (2)A(1)' state arising from singly occupying the nondegenerate a(1)' orbital. For W(3)O(9)(-), the (2)A(1) state was predicted to have essentially the same energy as the (2)A(1)' state at the CCSD(T) level with core-valence correlation corrections included and to be higher in energy or essentially isoenergetic with most DFT methods. The calculated VDEs from the CCSD(T) method are in reasonable agreement with the experimental values for both electronic states if estimates for the corrections due to basis set incompleteness are included. For M(3)O(9)(2-), the singlet state arising from doubly occupying the nondegenerate a(1)' orbital was predicted to be the most stable state for both M = Mo and W. However, whereas M(3)O(9)(2-) was predicted to be less stable than M(3)O(9)(-), W(3)O(9)(2-) was predicted to be more stable than W(3)O(9)(-).  相似文献   

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The total syntheses of beta-carboline alkaloids, (R)-(-)-pyridindolols (1, 5, and 6) are described. The two key steps involved are (1) a thermal electrocyclic reaction of the 3-alkenylindole-2-aldoxime 10 and (2) a thermal cyclization of 3-alkynylindole-2-aldoxime 11 to construct the beta-carboline N-oxides 8, which upon heating with acetic anhydride and sequential treatment with trifluoromethanesulfonic anhydride gave the triflates 18. The Stille coupling reaction of 18 with vinylstannane, followed by cleavage of MOM ether, afforded the 1-ethenyl-3-hydroxymethyl-beta-carboline (7a). Subsequent acetylation of 7a yielded the acetate 7b, which was subjected to the Sharpless asymmetric 1,2-dihydroxylation by AD-mix-beta to produce (R)-(-)-pyridindolol K2 (6). Selective acetylation of 6 was effected by Ac(2)O and collidine to form (R)-(-)-pyridindolol K1 (5). By contrast, hydrolysis of 6 provided (R)-(-)-pyridindolol (1).  相似文献   

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The speciation in the phosphitomolybdate system, H+-MoO4(2-)-(HP)O(3)2-, has been determined from combined potentiometric and 31P NMR measurements in 0.600 M Na(Cl) medium at 298(1) K. Potentiometric titration data were collected in the ranges 2.5<-log[H+]<6.2, 40.0相似文献   

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The synthesis, structural characterization, spectroscopic, and electrochemical properties of N(2)S(2)-ligated Ni(II) complexes, (N,N'-bis(2-mercaptoethyl)-1,5-diazacyclooctane)nickel(II), (bme-daco)Ni(II), and (N,N'-bis(2-mercapto-2-methylpropane)1,5-diazacyclooctane)nickel(II), (bme-daco)Ni(II), derivatized at S with alcohol-containing alkyl functionalities, are described. Reaction of (bme-daco)Ni(II) with 2-iodoethanol afforded isomers, (N,N'-bis(5-hydroxy-3-thiapentyl)-1,5-diazacyclooctane-O,N,N',S,S')halonickel(II) iodide (halo = chloro or iodo), 1, and (N,N'-bis(5-hydroxy-3-thiapentyl)-1,5-diazacyclooctane-N,N',S,S')nickel(II) iodide, 2, which differ in the utilization of binding sites in a potentially hexadentate N(2)S(2)O(2) ligand. Blue complex 1 contains nickel in an octahedral environment of N(2)S(2)OX donors; X is best modeled as Cl. It crystallizes in the monoclinic space group P2(1)/n with a = 12.580(6) ?, b = 12.291(6) ?, c = 13.090(7) ?, beta = 97.36(4) degrees, and Z = 4. In contrast, red complex 2 binds only the N(2)S(2) donor set forming a square planar nickel complex, leaving both -CH(2)CH(2)OH arms dangling; the iodide ions serve strictly as counterions. 2 crystallizes in the orthorhombic space group Pca2(1) with a = 15.822(2) ?, b = 13.171(2) ?, c = 10.0390(10) ?, and Z = 4. Reaction of (bme-daco)Ni(II) with 1,3-dibromo-2-propanol affords another octahedral Ni species with a N(2)S(2)OBr donor set, ((5-hydroxy-3,7-dithianonadiyl)-1,5-diazacyclooctane-O,N,N',S,S')bromonickel(II) bromide, 3. Complex 3 crystallizes in the orthorhombic space group Pca2(1) with a = 15.202(5) ?, b = 7.735(2) ?, c = 15.443(4) ?, and Z = 4. Complex 4.2CH(3)CN was synthesized from the reaction of (bme-daco)Ni(II) with 1,3-dibromo-2-propanol. It crystallizes in the monoclinic space group P2/c with a = 20.348(5) ?, b = 6.5120(1) ?, c = 20.548(5) ?, and Z = 4.  相似文献   

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A highly enantioselective synthesis of the versatile chiral synthons possessing one stereogenic center, (S)- and (R)-4-aryl-5-hydroxy-(2E)-pentenoate (3) was achieved based on the enzymatic reaction of (+/-)-3 with commercially available lipases MY-30 or OF-360 from Candida rugosa. Application of (S)-3 and (R)-3 to the total syntheses of(S)-curcuphenol (1), (S)-curcudiol (2), and (R)-curcuphenol (1), respectively, is described.  相似文献   

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The first complex to contain the N(2)O analogue P(2)O as a ligand is the tetranuclear cluster [{Cp*Fe}{Cp"Co}(3)(P(2)O)(PO)(P(2))] (1), which is formed by the oxidation in air of [{Cp*Fe}{Cp"Co}(2)(P(4))(P)] (Cp*=C(5)Me(5); Cp"=1,3-tBu(2)C(5)H(3)). The bent P(2)O ligand is doubly side-on as well as terminally coordinated (sigma,sigma,pi,pi) to the four metal atoms (see picture). In addition, 1 contains a PO and a P(2) ligand.  相似文献   

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The double Kabachnik–Fields condensation of primary amines with 2 equivalents of the other reagents (formaldehyde and a >P(O)H species, such as dialkyl phosphites, diphenylphosphine oxide, as well as the related dioxaphosphorine and oxaphosphorine derivatives) carried out under microwave conditions afforded the title products in 79–94% yields. The bis(phosphinoxidomethyl)amines were converted, after double deoxygenation, to the corresponding ring platinum complexes.

Additional information

ACKNOWLEDGMENTS

G. K. is grateful to Professor Harry R. Hudson (London Metropolitan University) for his advice. This project was supported by the Hungarian Scientific and Research Fund (OTKA K83118).  相似文献   

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以O2-2,4-二硝基苯基偶氮二醇盐(PABA/NO)为先导化合物,选择适当的仲胺作为偶氮二醇盐中相应的胺片段,并用碳氮键取代苯环5位的碳氧酯键,设计合成了化合物2a,2b和4a~4j,以期获得活性更强且稳定性好的抗肿瘤药物.目标化合物经1H NMR,13C NMR及HRMS进行了结构确证.生物活性测试结果表明,目标化合物可不同程度地抑制结肠癌HCT-116细胞的增殖,其中化合物4h的活性最强(IC50=7.945±0.421 μmol/L),优于PABA/NO(IC50=12.134±0.675 μmol/L).NO释放实验结果表明,此类化合物的NO释放量与细胞毒性呈正相关.化合物4h在HCT-116细胞中释放NO的量最多,约是正常细胞的2倍.此外,化合物4h在大鼠血浆中的体外稳定性显著优于PABA/NO,值得进一步研究.  相似文献   

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