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1.
Copper is next to iron the most important element in the biological transport, storage and in redox reactions of dioxygen. A bioanalogous activation of dioxygen with copper complexes is used for catalytical epoxidation, allylic hydroxylation and oxidative coupling of aromatic substrates, for example. With stereochemical information in form of chiral ligands, enantioselective reactions may be possible. Another aspect of interest on copper catalyzed reactions with dioxygen is that the exact mechanism and biological function of some enzymes (especially catechol oxidase) is yet not fully clear. For studies mimicking the copper-containing catechol oxidase appropriate chiral steroid ligands with defined stereochemistry and conformation have been synthesized. The four diastereomeric 16,17-aminoalcohols of the 3-methoxy-estra-1,3,5(10)-triene series have been condensed with salicylic aldehyde and different beta-ketoenols to the chiral ligand types 1-5. These compounds with different steric and electronic properties and different arrangements of the neighboring hydroxy and nitrogen functions were reacted with copper(II) acetate to copper complexes. The structure of these complexes will be discussed. The bioanalogous oxidation of 3,5-di-tbutyl-catechol (dtbc) to the corresponding quinone was catalyzed by most of the complexes, indicating their ability to activate dioxygen. The trans configurations c and d showed an activity one magnitude higher than the cis configurations a and b. Comparing compounds with the same diastereomeric configuration, the main influence was that of the peripheral R(1-3) substituents at the beta-ketoenaminic group which are useful for the fine-tuning of the properties of the copper atoms like redox potential and Lewis acidity.  相似文献   

2.
Galy N  Santelli M 《Steroids》2011,76(7):695-701
We described an efficient synthesis of (8β,9β,14β)-17β-acetyl-13β-p-bromophenyl-11,11-di(methoxycarbonyl)-3-methoxygona-1,3,5(10)-triene, (8β,9α,14β)-17β-acetyl-13β-p-bromophenyl-11,11-di(methoxycarbonyl)-3-methoxygona-1,3,5(10)-triene, (8β,9β,14β)-13 β-p-bromophenyl-11,11-di(methoxycarbonyl)-17β-(2-hydroxyethyl)-3-methoxygona-1,3,5(10)-triene, and (8β,9β,14β)-13β-p-bromophenyl-11,11-di(methoxycarbonyl)-17β-(2-oxoxyethyl)-3-methoxygona-1,3,5(10)-triene in five or six steps from 1-iodo-4-methoxybenzocyclobutene and readily available materials.  相似文献   

3.
4.
The epoxidation, the addition of hypobromous acid, and the hydroboration of 3-methoxy-13alpha-estra-1,3,5(10),16-tetraene 1 with diborane, catecholborane, and 9-BBN were investigated in order to determine the stereochemical outcome and to synthesize new 13alpha-estra-1,3,5(10)-trienes for biological and conformational investigations. It was shown that the sterically demanding reagent 9-BBN participated in a preferred beta attack (53% 16betaOH 10, 34% 17betaOH 8, 13% 16alphaOH 11). This stereochemical result is in agreement with that from another cis addition reaction, the recently described OsO4 dihydroxylation of 1 [Steroids 68 (2003) 113]. With smaller reagents such as B2H6, catecholborane, or magnesium monoperoxyphthalate, a diminished stereoselectivity was observed with only a slight excess of beta attack. The ionic trans addition of hypobromous acid gave two 17-bromo-16-alcohols with 16beta,17alpha (4, 76%) and 16alpha,17beta configuration (5, 24%) formed by trans cleavage of the 16,17alpha- and beta-bromonium ion at position 16. The same regioselective and stereoselective course was found for the cleavage of the 16alpha,17alpha- and 16beta,17beta-epoxides (3 and 2) with hydrazoic acid (3-->16betaN3,17alphaOH 7, 2-->16alphaN3,17betaOH 6). The stereochemistry of the addition reactions to 1 can be explained in terms of a twist-boat conformation involving the C ring of compound 1. From a synthetic viewpoint the synthesis of the beta-epoxide 2 from the bromohydrin 4, the cleavage of this epoxide to 16alpha-substituted-17beta-hydroxy compounds, such as 6, and hydroboration/oxidation with 9-BBN to the hitherto unknown 16beta-hydroxy compound 10 are useful procedures. The bromohydrin 5 is the first 13alpha-steroid with a 17beta-bromo substituent. X-ray analysis revealed twist-boat and 16beta-envelope conformations for rings C and D, respectively.  相似文献   

5.
The respiration of Ehrlich ascites tumor cells is inhibited by 3-ethoxy-2-oxobutyraldehyde bis (thiosemicarbazanato) copper (II). State 3 oxidative phosphorylation in mitochondria from tumor cells is also inhibited, with the effect more pronounced using glutamate or pyruvate-malate as substrates than with succinate. The disruption of oxidative phosphorylation in bovine heart mitochondria is qualitatively similar. The principal site of inhibition is in coupling site one, energetically between the electron transport site chain and the locus of uncoupling by 2,4-dinitrophenol. This appears to contain thiol groups which are oxidized by the complex. For a series of bis (thiosemicarbazonato) copper complexes, the extent of inhibition of heart mitochondrial oxidative phosphorylation is correlated with the reduction potentials of the complexes and with their in vitro cytotoxic effects against Walker 256 carcinoma tumor cells.  相似文献   

6.
The anticoagulant and estrogenic effects of prolame, N-(3-hydroxy-1,3,5(10)-estratrien-17 beta-yl)-3-hydroxypropylamine, are described. A single subcutaneous injection of prolame in male mice, ovariectomized mice, adult and infant male rats, produced dose-dependent increases of blood clotting time, which could be observed with the larger doses even after 4 days. In ovariectomized mice, prolame produced vaginal cornifications of shorter duration than those produced by estradiol-17 beta. The evidence suggests that, in contrast with currently used estrogens, prolame would not generate cardiovascular accidents if used for the treatment of prostatic carcinoma; it could also be exceptionally effective for the prevention of thrombosis.  相似文献   

7.
The iron(III)-1,2-dimethyl-3-hydroxy-4-pyridinone (Deferiprone) system is carefully characterized by a combined potentiometric-spectrophotometric procedure at 25 and 37 degrees C at different ionic strengths, and by thermochemical and quantum-chemical studies. The main purpose of this work was to determine how the temperature dependence of both complex-formation and protonation constants can affect the pFe values on going from 25 degrees C (pFe is normally calculated using 25 degrees C stability constants) to the physiological temperature of 37 degrees C at which chelating agents are active in vivo. The copper(II)-Deferiprone system is also studied and the iron(III)-Deferiprone distribution diagrams in presence of variable copper(II) amounts are shown so as to explain possible side effects due to a competing metal ion during the chelating therapy of iron overload.  相似文献   

8.
Copper(II) complexes with glycyl-DL-alpha-amino-n-butyric acid (H2gly-DL-but), glycyl-DL-valine (H2gly-DL-val), glycyl-DL-norleucine (H2gly-DL-norleu), glycyl-DL-threonine (H2gly-DL-thr), glycyl-DL-serine (H2gly-DL-ser), glycyl-DL-phenylalanine (H2gly-DL-phe), and glycyl-L-valine (H2gly-L-val), have been prepared and characterized by IR, powder diffuse reflection, CD and ORD spectra, and magnetic susceptibility measurements, and by single-crystal X-ray diffraction. The crystal structures of the copper complex with H2gly-DL-but, the copper complex with H2gly-DL-val, and [Cu(gly-L-val)]n.0.5nH2O have been determined by a single-crystal X-ray diffraction method. As for the structure of the copper complex with H2gly-DL-but, the configuration around the asymmetric carbon atom is similar to that of [Cu(gly-L-val)]n.0.5nH2O. Therefore it is concluded that the copper complex with H2gly-DL-but is [Cu(gly-L-but)]n.nH2O. On the contrary, as for the structure of the copper complex with H2gly-DL-val, the configuration around the asymmetric carbon atom is different from that of [Cu(gly-L-val)]n.0.5nH2O. Therefore it is concluded that the copper complex with H2gly-dl-val is [Cu(gly-D-val)]n.0.5nH2O. So during the crystallization of the copper(II) complexes with H2gly-DL-but and H2gly-DL-val, spontaneous resolution has been observed; the four complexes have separated as [Cu(gly-D-but)]n.nH2O, [Cu(gly-L-but)]n.nH2O, [Cu(gly-D-val)]n.0.5nH2O, and [Cu(gly-L-val)]n.0.5nH2O, respectively. [Cu(gly-L-but)]n.nH2O is orthorhombic with the space group P2(1)2(1)2(1). [Cu(gly-D-val)]n.0.5nH2O and [Cu(gly-L-val)]n.0.5nH2O are monoclinic with the space group C2. In these complexes, the copper atom is in a square-pyramidal geometry, ligated by a peptide nitrogen atom, an amino nitrogen atom, a carboxyl oxygen atom, and a carboxyl oxygen atom and a peptide oxygen atom from neighboring molecules. So these complexes consist of a two-dimensional polymer chain bridged by a carboxyl oxygen atom and a peptide oxygen atom from neighboring molecules. The axial oxygen atom is located above the basal plane and the side chain of an amino acid is located below it. These polymer chains consist of only one or the other type of optical isomers; no racemic dipeptides are found. Therefore, spontaneous resolution has been observed in the crystallization of copper(II) complexes with H2gly-DL-but and H2gly-DL-val. The crystal structure of [Cu(gly-D-val)]n.0.5nH2O agrees almost completely with that of [Cu(gly-L-val)]n.0.5nH2O, except for the configuration around the asymmetric carbon atom.  相似文献   

9.
Formation constants for the complexes formed between copper(II) and glycinehydroxamic acid (H2NCH2CONHOH) have been measured potentiometrically at 25.0 °C and I = 0.10 M (NaClO4). The existence of a dimeric copper(II) species has been shown from the line broadening of the epr spectrum of a solution at room temperature. The structures of the complexes are discussed and conclusions are drawn based on absorption and epr spectra.  相似文献   

10.
The preparation of high specific activity 3H labeled 16α-hydroxyestrone and of the 6-hemisuccinate of the ketol metabolite of estradiol is described. The synthetic procedures which were required to produce these essential ingredients of a radioimmunoassay for 16α-hydroxyestrone required multistep syntheses because of the multifunctional and labile nature of the metabolite.  相似文献   

11.
The primary hydroxy functions of 16alpha-hydroxymethyl-3-methoxy-13alpha-estra-1,3,5(10)-trien-17beta-ol (3a) and 16beta-hydroxymethyl-3-methoxy-13alpha-estra-1,3,5(10)-trien-17alpha-ol (4a) were stereoselectively transformed into good leaving groups. On alkaline methanolysis of the 16-halomethyl or 16-tolylsulfonyloxymethyl derivatives, a new D-seco-13alpha-estrone derivative was obtained in high yield.  相似文献   

12.
Three new Cu(II) complexes, [Cu2(C3H2O4)(phen)2(H2O)3](NO3)2(H2O)2 (1) (C3H2O4 = malonate, phen = 1,10-phenanthroline), [Cu2(C4H4O4)(phen)2(H2O)2](NO3)2 (2) (C4H4O4 = succinate), and {[Cu2(phen)2(H2O)(NO3)]2(C5H6O4)2}(NO3)2 (3) (C5H6O4 = glutarate) have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. The X-ray analysis reveals that the structures of 1 and 2 are of dinuclear copper(II) complexes bridged by malonate and succinate dianions, respectively, and 3 is a tetranuclear species formed by two {[Cu2(phen)2(H2O)(NO3)](C5H6O4)} fragments. The copper ions in 1 and 3 show square-pyramidal coordination geometry, while the copper ions in 2 exhibit a square planar geometry. In each complex, the dicarboxylate ligand is coordinated to copper ions as a chelate and monodentate (1), bis-monodentate (2), and bis-bridging ligand toward the copper ions with syn-syn coordination mode (3).  相似文献   

13.
The anticoagulant and estrogenic effects of hexolame, N-(3-hydroxy-1,3,5(10)-estratrien-17 beta-yl)-6-hydroxyhexylamine, are described. A single subcutaneous injection of hexolame in adult and infant male mice produced dose-dependent increases in blood clotting time which could be observed even after 2 days. In ovariectomized mice, hexolame produced vaginal cornification (estrogenic response). The data suggested that if used in the treatment of prostatic cancer, hexolame, like prolame, would not induce cardiovascular accidents. It could also be useful in the prevention of thrombosis.  相似文献   

14.
The synthesis and molecular structure of prolame, N-(3-hydroxy-1,3,5(10)-estratrien-17 beta-yl)-3-hydroxypropylamine, is described. It was characterized by ir, nmr, mass spectrometry and chemical analysis. The crystal structure of this compound was determined by single-crystal x-ray diffraction. Prolame belongs to space group P212121. Cell dimensions are: a = 8.356(2), b = 13.343(4) and c = 16.119(4) A. Z = 4; R = 4.1%.  相似文献   

15.
Complexes [Cu(HSas)(H2O)] · 2H2O (H3Sas = N-(2-hydroxybenzyl)-l-aspartic acid) (1), [Cu(HMeSglu)(H2O)] · 2H2O (H3MeSglu = (N-(2-hydroxy-5-methylbenzyl)-l-glutamic acid) (2), [Cu2(Smet)2] (H2Smet = (N-(2-hydroxybenzyl)-l-methionine) (3), [Ni(HSas)(H2O)] (4), [Ni2(Smet)2(H2O)2] (5), and [Ni(HSapg)2] (H2Sapg = (N-(2-hydroxybenzyl)-l-aspargine) (6) have been synthesized and characterized by chemical and spectroscopic methods. Structural determination by single crystal X-ray diffraction studies revealed 1D coordination polymeric structures in 2 and 4, and hydrogen-bonded network structure in 5 and 6. In contrast to previously reported coordination compounds with similar ligands, the phenol remains protonated and bonded to the metal ions in 2 and 4, and also probably in 1. However, the phenolic group is non-bonded in 6.  相似文献   

16.
The synthesis and structural characterization of four new copper compounds with formula [Cu(crot)2(isn)2(Hcrot)·H2O] (1), [Cu(oda)(isn)2] (2), [Cu(crot)2(nia)2·(H2O)] (3) and [Cu(oda)(nia)] (4) (crot = trans-2-butenoate, oda = oxydiacetate, isn = isonicotinamide, nia = nicotinamide) is reported. The complexes extend into 3D supramolecular structures by means of hydrogen bonds. EPR spectra of powder samples of the compounds are reported.  相似文献   

17.
Circular dichroism (CD) spectra of individual mixed-ligand copper(II) complexes of 1,3-dicarbonyl compounds, (1S)- or (1R)-3-hydroxymethylene camphor, (1S)-3-trifluoroacetyl camphor, or (1R)-2-hydroxymethylene menthone, and α-amino acids, alanine, valine, proline, or their N-alkyl derivatives, were calculated from CD spectra of equilibrium solutions containing the above constituents in methanol or ethylene dichloride. Diastereomeric mixed-ligand complexes incorporating identical dicarbonyl but enantiomeric N-alkyl-α-amino acid ligands exhibit quasi-enantiomeric CD spectra. Unsubstituted amino acids, on the contrary, will make no decisive contributions to the net optical activity spectrum of the mixed-ligand complexes. Formation constants of diastereomeric mixed-ligand complexes have been calculated from data on disproportionation of the latter into corresponding equally paired complexes. Enantioselectivity was demonstrated to amount to up to 700 cal/mol. Possible steric structures of mixed-ligand complexes are discussed. © 1993 Wiley-Liss, Inc.  相似文献   

18.
《Inorganica chimica acta》2006,359(5):1573-1581
From the 2,4-bis(cyanamido)cyclobutane-1,3-dione dianion (2,4-NCNsq2−), two copper complexes [Cu2(PPh3)4(PhCN)2(μ-2,4-NCNsq)] · PhCN (1) and [Cu(dien)(μ-2,4-NCNsq) · H2O]n (2) have been synthesized and characterized by IR and electronic absorption spectroscopies. Their structures have been determined by X-ray crystallography. Complex 1 is a dinuclear copper(I) compound with a 2,4-NCNsq2− ligand bridging two copper atoms through the nitrile nitrogen atoms. Complex 2 appears as a 3D network constituted of copper(II) atoms bridged by 2,4-NCNsq2− dianions. This complex presents an unexpected coordination mode of the bis(cyanamido) ligands which are both coordinated via the nitrile functions and via the amido nitrogen atoms of the NCN groups.  相似文献   

19.
A series of Ni(II) and Cu(II) complexes of the hexaaza macrocycles, 3,6,9,17,20,23-hexaazatricyclo[23.3.1.111,15]triaconta-1(29),11(30),12,14,25,27-hexaene (L1) and 3,6,9,16,19,22-hexaazatricyclo[22.2.2.211,14]triaconta-1(26),11(29),12,14(30),24(28),25-hexaene (L2), have been prepared and the crystal structures determined for [Ni2L1(O2CCH3)2(H2O)2](ClO4)2 (1), [Ni2L2(DMF)6](ClO4)4 · 2H2O (2), {[Cu2L2Br(O2CCH3)](ClO4)2}n (3), [Cu2L2(μ-CO3)(H2O)2]2(ClO4)4 · 8H2O (4), [Cu2L2(O2CCH3)2](BF4)2 (5), and [Cu2L1(μ-imidazolate)Br]2Br4 · 6H2O (6). In these complexes, two metal centers are bound per ligand; in 1 and 3-6, the N3 subunits of L1 or L2 coordinate meridionally to the metal centers, whilst in 2, each N3 subunit in L2 adopts a facial mode of coordination. The binuclear cations in 1 and 2 have chair-like conformations, with the distorted octahedral Ni(II) coordination spheres completed by terminal water and a bidentate acetate ligand in 1 and three DMF ligands in 2. The Cu(II) centers in 3-6 generally reside in square planar environments, although a weakly binding ligand enters the coordination sphere in some cases, generating a distorted square pyramidal geometry. The binuclear [Cu2L2]4+ units in 3, 4 and 5 adopt similar bowl-shaped conformations, stabilized by H-bonding interactions between pairs of amine groups from L2 and a perchlorate or tetrafluoroborate anion. In 3, the binuclear units are linked through acetate groups, bridging in a syn-anti fashion, to produce a zig-zag polymeric chain structure, whilst 4 incorporates a tetrameric cation consisting of two binuclear units linked via a pair of carbonate bridges. Compound 6 features an imidazolate bridge between the two Cu(II) centers bound by L1. Pairs of [Cu2L1(μ-imidazolate)]3+ units are then weakly linked through a pair of bromide anions.  相似文献   

20.
Copper(II) and nickel(II) complexes of potentially N2O4 Schiff base ligands 2-({[2-(2-{2-[(1-{2-hydroxy-5-[2-phenyl-1-diazenyl]phenyl}methylidene)amino] phenoxy}ethoxy) phenyl]imino}methyl)4-[2-phenyl-1-diazenyl]phenol (H2L1) and 2-({[2-(4-{2-[(1-{2-hydroxy-5-[2-phenyl-1-diazenyl]phenyl}methylidene)amino] phenoxy}butoxy) phenyl]imino}methyl)4-[2-phenyl-1-diazenyl]phenol (H2L2) prepared of 5-phenylazo salicylaldehyde (1) and two various diamines 2-[2-(2-aminophenoxy)ethoxy]aniline (2) and 2-[4-(2-aminophenoxy)butoxy]aniline (3) were synthesized and characterized by a variety of physico-chemical techniques. The single-crystal X-ray diffractions are reported for CuL1 and NiL2. The CuL1 complex contains copper(II) in a near square-planar environment of N2O2 donors. The NiL2 complex contains nickel(II) in a distorted octahedral geometry coordination of N2O4 donors. In all complexes, H2L1 behaves as a tetradentate and H2L2 acts as a hexadentate ligand. Cyclic voltammetry of copper(II) complexes indicate a quasi-reversible redox wave in the negative potential range.  相似文献   

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