Synthesis of tris(β,β,γ-oximinoalkyl)amines from aliphatic nitro compounds and methyl vinyl ketone

A general strategy for the assembly of previously unknown tris(β,β,γ-oximinoalkyl)amines from aliphatic nitro compounds and methyl vinyl ketone is described. The strategy involves N,N-bis(siloxy)enamines as key intermediates. The latter are accessible by double silylation of alkylnitro compounds. Nickel(II) and copper(II) complexes of tris(β,β,γ-oximinoalkyl)amines are prepared and structurally characterized.     

Condensation d'acides amines sur des meso-amino-2-phenyl porphyrines

The condensation of aminoacids on meso-tetra-(2-aminophenyl) and meso-α,γ-bis-(2,6-diaminophenyl)porphyrins is reported.     

Superexchange in copper(II) Dimers. 3. Synthesis and characterization of binuclear adducts of copper(II) halides with some α,β-dione dioximes

Copper(II) halides, CuX₂ (X = Br^?, Cl^?), have been combined in non-aqueous medium with various α,-β-dione dioxime (α,β-dodoH) ligands to produce new 1:1 adducts, the di-μ-halo-bis[halo(α,β-dodoH)copper(II)] dimers. These are: Di-μ-bromo-bis[bromo(ethanedialdioxime)copper(II)]; di-μ-bromo-bis[bromo(diphenylethanedione dioxime)copper(II)]; di-μ-bromo-bis-[bromo(9,10phenanthrenedione dioxime)copper(II)]; di-μ-chloro-bis-[chloro(9,10-phenanthrenedione dioxime)copper(II)]. The materials were characterized by conventional methods. The results clearly indicate that the compounds crystallize in discrete dimers, quite consistent with the results of closely related dimers studied earlier.     

Palladium mediated synthesis of conjugated E or Z enones and unsymmetrical divinyl ketones. one-pot preparation of isoegomaketone

The palladium (o) catalyzed coupling of acyl halides or anhydrides with alkenyl copper reagents furnishes α,β ethylenic ketones and α,β-α,β' diethylenic ketones in high yield. The substitution pattern of the alkenyl copper reagent, directly obtained by carbocupration of alkynes, is fully retained. Anhydrides of Z-ethylenic acids also retain their Z stereochemistry. β-halogeno-vinyl ketones react under the above conditions to afford α,β-γ,δ dienones. An efficient one-pot synthesis of Z or ε isoegomaketone is reported.     

胶原/明胶的结构(构象)与性能研究V.铜离子与明胶中不同构象组分络合形态的研究

利用CM-52离子交换层析和无火焰原子吸收光谱法对明胶中铜离子与不同构象组分络合形态进行了研究。其研究结果表明:明胶中的铜离子是与明胶大分子中的不同构象(α、β和γ)组分中的游离基因以络合的形式稳定地存在着,铜离子与不同构象的络合能力大小可以排列成以下的顺序:(γ>β>α).金属铜与不同构象络合的能力是如此之强,以致明胶中微量的铜离子可以认为是明胶大分子结构中的一部分。     

Syntheses and evaluation of 7-deoxycholic amide-based tweezer-type copper(II) ion-selective ionophores

Seven tweezer-type copper(II) ion-selective ionophores; that is, 3α,12α-bis[[[N-(R)thiocarboxamino]acetyl]oxy]-N,N-dioctyl-5β-cholan-24-amides and 3α,12α-bis[[[N-(R)thiocarboxaminomethyl]acetyl]oxy]-N,N-dioctyl-5β-cholan-24-amides (R = alkyl and phenyl), were newly designed and synthesized. Their potentiometric evaluation of the poly(vinyl chloride) (PVC) membranes showed excellent affinity and selectivity to copper(II) ions over those of other transition metal ions and alkali/alkaline earth metal ions. These membranes exhibited super-Nernstian responses toward copper(II) ions (34-36 mV/decade), with detection limits of 10⁻⁶-10⁻⁷ M.     

A novel synthetic route to fused propenochlorin and benzochlorin photodynamic therapy probes

Reaction of meso-(2-formylvinyl)octaethylporphyrin with (CH3)3SiCN-Cu(OTf)2 produced unexpected 10(3)-trimethylsiloxyl and 10(3)-hydroxyl fused propenochlorins which, in H2SO4, underwent subsequent migration of the 8-ethyl group to the 10(3)-position of the exocyclic benzene ring to form a novel benzochlorin.     

Stereoselective syntheses of γ-alkyl (aryl)-α,β-dihydroxy-γ-butyrolactones and naturally occurring lipid guggultetrol

γ-Oxo-butyramides derived from tartaric acid serve as excellent precursors for the synthesis of γ-alkyl (aryl)-α,β-dihydroxy-γ-butyrolactones and for the synthesis of tetrols containing three contiguous stereogenic centres. The methodology presented here is general for the synthesis of γ-alkyl (aryl)-α,β-dihydroxy-γ-butyrolactones. Utility of the chiral building block was demonstrated by the synthesis of naturally occurring lipid guggultetrol.     

Enantioselective gem-chlorofluorination of active methylene compounds using a chiral spiro oxazoline ligand

Highly enantioselective gem-chlorofluorination of active methylene compounds was carried out by using a copper(II) complex of a chiral spiro pyridyl monooxazoline ligand. This reaction yielded α-chloro-α-fluoro-β-keto esters and α-chloro-α-fluoro-β-keto phosphonates with up to 92% ee. The resulting dihalo β-keto ester was converted into various α-fluoro-α-heteroatom-substituted carbonyl compounds via nucleophilic substitution without loss of optical purity. A fully protected β-amino acid with a gem-chlorofluoromethylene function was also synthesized.     

Synthesis,Crystal Structure and DNA Cleavage Activity of a Ternary Copper(Ⅱ)Complex of Dipyrido[3,2-d:2',3'-f]-quinoxaline and Glycine

A ternary copper(II) complex, [Cu(Dpq)(Gly)(H₂O)]·NO₃·1.5H₂O (Dpq=dipyrido[3,2‐d:2′,3′‐f]quinoxaline, Gly=glycine), has been synthesized and structurally characterized. The complex crystallized in a triclinic system with space group P‐1, a=6.6979(9) Å, b=7.6351(10) Å, c=18.980(2) Å, α=85.815(2) °, β=88.182(2) °, γ=71.203(2) °. The five‐coordinate copper(II) center is a distorted square pyramid. Absorption spectra, fluorescence spectra and CD spectra showed that there were interactions between the copper complex and DNA through a groove binding mode. The complex exhibited efficient DNA cleavage activity at micromolar concentration in the presence of ascorbate with hydroxyl radicals as the active species.     

An efficient synthetic method for Z-fluoroalkene dipeptide isosteres: Application to the synthesis of the dipeptide isostere of Sta-Ala

Reaction of γ,γ-difluoro-α,β-enoates having a δ-hydroxyl group with trialkylaluminum (R₃Al) was found to be promoted by CuI·2LiCl and to proceed in SN2′ manner giving rise to the α-alkylated (Z)-γ-fluoro-β,γ-enoates, while reductive defluorination of γ,γ-difluoro-α,β-enoates with Me₂CuLi followed by reaction with alkyl halides provided the corresponding (Z)-α-alkylated products in high yields. The latter reaction was applied to the preparation of the dipeptide (Z)-fluoroalkene isostere of Sta-Ala, which is the central dipeptide unit in Pepstatin, a natural inhibitor of aspartate proteases.     

meso－5，10，15，20－四（3，4，5－三甲氧基苯基）卟啉的晶体和分子结构

用Ｘ－射线测定了ｍｅｓｏ－５，１０，１５，２０－四（３，４，５－三甲氧基苯基）卟啉的溶剂（正庚烷）合物（ＴＴＯＭＰＰ·２Ｃ＿７Ｈ＿（１６））的晶体结构。实验表明，该化合物（Ｃ＿（７０）Ｈ＿（８６）Ｎ＿４Ｏ＿（１２））的晶体属三斜晶系，空间群Ｐ１，ａ＝８．７４９（６），ｂ＝１５．１２９（６），ｃ＝１６．４４９（３），ａ＝６０．０７（３），β＝７０．６４（４），γ＝８１．７０（５），Ｖ＝１７７９．６，Ｍ＿ｒ＝１１７５．４９，Ｚ＝１，Ｄ＿ｃ＝１．０９７ｇ／ｃｍ￣３，μ＝０．６９７ｃｍ￣（－１），Ｆ（０００）＝６３０。讨论了卟啉环上取代基的电子和立体效应及卟啉与铁（Ⅲ）离子配位后铁（Ⅲ）离于对卟啉结构参数的影响。     

New derivatives of 4-quinaldinol

The reactions of 1, 1, 3-trichloro-1-propene and also 1, 1, 1-trichloro-2-propene with acetoacetic ester gave α-(γ, γ-dichlorallyl)acetoacetic ester (I). In the reactions with aniline and o- and p-toluidines, the corresponding α-(γ, γ-dichloroallyl)-β-arylamino-crotonic esters were produced, thermal cyclization of which gave 2-methyl-3-(γ, γ-dichloroallyl)-4-hydroxyquinoline (II) and its 6CH₃- (III) and 8CH₃- (IV) homologs. With phosphorus oxychloride, II–IV gave the corresponding 4-chloro-substituted quinolines (V–VII); with concentrated sulfuric acid, II–VII were converted into the corresponding β-quinolinylpropionic acids VIII–XIII.     

Interaction between N-phosphoryl-α, β- and γ-amino acids and nucleosides

The reactions of four different N-(O,O′-diisopropyl) phosphoamino acids (DIPP-aa),such as N-phosphoryl-L-α-alanine (DIPP- L-α-Ala),N-phosphoryl-D-α-alanine (DIPP-D-α-Ala),N-phosphoryl-β-alanine (DIPP-β-Ala) and N-phosphoryl-γ-amino butyric acid (DIPP-γ-Aba),and four nucleosides,adenosine (A),guanosine (G),cytidinc (C) and uridine (U),were studied by electrospray ionization tandem mass spectrometry (ESI-MS/MS) and HPLC/ESI-MS.DIPP-L-α-Ala and DIPP-D-α-Ala produced the same phosphorylated nucleosidcs,dinucleotidcs and phosphoroligopeptide.However,DIPP-β-Ala and DIPP-γ-Aba gave no relevant products.     

Study on the Reaction of CIS-1-Acetyl-2-Aryl-6,6-Dimethyl-5,7-Dioxospiro-[2,5]-4,8-Octadiones with Methanol

Cis-l-acetyl-2-aryl-6,6-dimethyl-5,7-dioxo-spiro-[2,5]-4,8-octadiones 3a-d (X=p-CH₃, p-Cl, H, p-NO₂) reacted with anhydrous methanol in a sealed tube at 80°C to form trans, cis-α-carbomethoxy-β-(α′-methoxy-α′-aryl)-γ-methoxy-γ-methyl-γ-butyrolactones 4a-d and cis, cis-α-carbomethoxy-β-(α′-methoxy-α′-aryl)-γ-methoxy-γ-methyl-γ-butyrolactones 5a-d in good yield.     

Effect of Successive Meso-Phenyl Substitution on the Dissociation Kinetics of Copper(II) Octaethylporphyrin

We have synthesized complexes of copper(II) with octaethyl-, 5-phenyl octaethyl-, 5,15-diphenyl octaethyl-, and 5,10,15,20-tetraphenyl octaethylporphyrins. We have studied their dissociation kinetics in mixed solvents AcOH – H₂SO₄ at temperatures of 298 K to 343 K. We have determined the complete kinetic equations for dissociation of copper porphyrins for different compositions of the binary solvent AcOH – H₂SO₄. We provide a rational basis for electronic and steric effects on the stability of copper(II) octaethylporphyrin upon meso-phenyl substitution as a function of the degree of substitution.     

Diastereoselective addition of silyl metals to γ-alkoxy substituted α,β-unsaturated esters

Dimethylphenylsilyllithium adds to Z-γ-alkoxy-α,β-unsaturated esters to produce almost exclusively (i) the anti-adducts when the reaction is carried out in THF and (ii) the anti-adduct when carried out in the presence of HMPA. Poor stereocontrol is achieved with stereoisomeric E-γ-alkoxy-α,β-unsaturated esters.     

Voltammetric determination of Cu(II) in natural waters and human hair at a meso-2,3-dimercaptosuccinic acid self-assembled gold electrode

An electrochemical sensor for the detection of copper(II) ions is described using a meso-2,3-dimercaptosuccinic acid (DMSA) self-assembled gold electrode. First in ammonia buffer pH 8, copper(II) ions complex with self-assembled monolayer (SAM) via the free carboxyl groups on immobilized meso-2,3-dimercaptosuccinic acid (accumulation step). Then, the medium is exchanged to acetate buffer pH 4.6 and the complexed Cu(II) ions are reduced in negative potential of −0.3 V (reduction step). Following this, reduced coppers are oxidized and detected by differential pulse (DP) voltammetric scans from −0.3 to +0.7 V (stripping step). The effective parameters in sensor response were examined. The detection limit of copper(II) was 1.29 μg L⁻¹ and R.S.D. for 200 μg L⁻¹ was 1.06%. The calibration curve was linear for 3-225 μg L⁻¹ copper(II). The procedure was applied for determination of Cu(II) to natural waters and human hairs. The accuracy and precision of results were comparable to those obtained by flame atomic absorption spectroscopy (FAAS).     

Synthesis and properties of new chelating resin with a spacer containing alpha-nitroso-beta-naphthol as the functional group

A new chelating ion-exchange resin with a spacer CH₂-NH-C₆H₄- based on a microreticular chloromethylated styrene-divinylbenzene copolymer containing α-nitroso-β-naphthol as a functional group has been synthesized. The sorption characteristics for manganese(II), iron(III), cobalt(II), nickel(II), copper(II), and zinc(II) have been investigated over the pH range 1.0–7.0. The resin is highly stable in acidic and alkaline medium. Iron(III) and cobalt(II); copper(II) and iron(III) are separated very effectively in a column operation by stepwise elution.     

Cationic diiron and diruthenium μ-allenyl complexes: synthesis, X-ray structures and cyclization reactions with ethyldiazoacetate/amine affording unprecedented butenolide- and furaniminium-substituted bridging carbene ligands

The novel cationic diiron μ-allenyl complexes [Fe(2)Cp(2)(CO)(2)(μ-CO){μ-η(1):η(2)(α,β)-C(α)(H)=C(β)=C(γ)(R)(2)}](+) (R = Me, 4a; R = Ph, 4b) have been obtained in good yields by a two-step reaction starting from [Fe(2)Cp(2)(CO)(4)]. The solid state structures of [4a][CF(3)SO(3)] and of the diruthenium analogues [Ru(2)Cp(2)(CO)(2)(μ-CO){μ-η(1):η(2)(α,β)-C(α)(H)=C(β)=C(γ)(R)(2)}][BPh(4)] (R = Me, [2a][BPh(4)]; R = Ph, [2c][BPh(4)]) have been ascertained by X-ray diffraction studies. The reactions of 2c and 4a with Br?nsted bases result in formation of the μ-allenylidene compound [Ru(2)Cp(2)(CO)(2)(μ-CO){μ-η(1):η(1)-C(α)=C(β)=C(γ)(Ph)(2)}] (5) and of the dimetallacyclopentenone [Fe(2)Cp(2)(CO)(μ-CO){μ-η(1):η(3)-C(α)(H)=C(β)(C(γ)(Me)CH(2))C(=O)}] (6), respectively. The nitrile adducts [Ru(2)Cp(2)(CO)(NCMe)(μ-CO){μ-η(1):η(2)-C(α)(H)=C(β)=C(γ)(R)(2)}](+) (R = Me, 7a; R = Ph, 7b), prepared by treatment of 2a,c with MeCN/Me(3)NO, react with N(2)CHCO(2)Et/NEt(3) at room temperature, affording the butenolide-substituted carbene complexes [Ru(2)Cp(2)(CO)(μ-CO){μ-η(1):η(3)-C(α)(H)[upper bond 1 start]C(β)C(γ)(R)(2)OC(=O)C[upper bond 1 end](H)] (R = Me, 10a; R = Ph, 10b). The intermediate cationic compound [Ru(2)Cp(2)(CO)(μ-CO){μ-η(1):η(3)-C(α)(H)[upper bond 1 start]C(β)C(γ)(Me)(2)OC(OEt)C[upper bond 1 end](H)](+) (9) has been detected in the course of the reaction leading to 10a. The addition of N(2)CHCO(2)Et/NHEt(2) to 7a gives the 2-furaniminium-carbene [Ru(2)Cp(2)(CO)(μ-CO){μ-η(1):η(3)-C(α)(H)[upper bond 1 start]C(β)C(γ)(Me)(2)OC(OEt)C[upper bond 1 end](H)](+) (11). The X-ray structures of 10a, 10b and [11][BF(4)] have been determined. The reactions of 4a,b with MeCN/Me(3)NO result in prevalent decomposition to mononuclear iron species.