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1.
The employment of periodate oxidation in the chemistry of nucleic acids and their components is reviewed. The reaction mechanism, structural requirements to substrates, and synthesis of dialdehyde derivatives of nucleosides, nucleotides, and oligonucleotides are discussed in the first part. The second part involves chemical, physico-chemical, and biological properties of the dialdehyde derivatives, as well as their use for the affinity modifications of proteins.  相似文献   

2.
A procedure for preparing derivatives of dialdehyde dextran-glass-carriers and their use for immobilization of trypsin is described. The dextran to the support as well as the trypsin to dextran were covalently immobilized via dialdehyde groups. The relative activity of immobilized trypsin in these enzyme-carrier-complexes amounted 17.3% and 20,4 (determined with alpha-N-Benzoyl-DL-arginine-p-nitroanilid) and 8,2% and 11.6% (determined with casein).  相似文献   

3.
Condensation of carminomycin or daunorubicin with glutaric dialdehyde in the presence of NaBH3CN yielded 3'-deamino-3'-piperidinocarminomycin or 3'-deamino-3'-piperidinodaunorubicin and corresponding (13-R, S)-dihydroderivatives. To prepare similar derivatives of 14-hydroxycarminomycin or doxorubicin, 13-dimethylketals of 14-bromocarminomycin or 13-bromodaunorubicin were used in the reaction of reductive alkylation with glutaric or glycolic dialdehyde to give 3'-deamino-3'-piperidino- or 3'-deamino-3'-morpholino derivatives of 13-dimethylketals of 14-bromocarminomycin or daunorubicin, respectively. After deblocking and subsequent hydrolysis of these compounds 3'-deamino-3'-piperidino- and 3'-deamino-3'-morpholino derivatives of 13-hydroxycarminomycin or doxorubicin were prepared. Reduction of the antibiotic derivatives under mass spectrometry conditions was demonstrated.  相似文献   

4.
Abstract

The preparation of ON derivatives with regiospecifically incorporated dialdehyde reactive groups and their successful use as affinity labels was described.  相似文献   

5.
The synthesis of bifunctional pyridine, pyrimidine, pyridone, quinoline and acridine derivatives was investigated using dialdehyde as a precursor. A rapid and efficient method was developed for the synthesis of a range of bifunctional monocyclic, bicyclic and tricyclic products related to 1,4-DHPs with the aim of finding new classes of biologically active compounds.  相似文献   

6.
Dialdehyde derivatives of cellulose (CE) and α-cyclodextrin (α-CD) were prepared by the periodate oxidation method. Linkage formation between cellulose dialdehyde (dial-CE) and bovine serum albumin (BSA) proceeded rapidly at pH 9.0 and gave a maximum yield at about 30 hr. Among the various amino compounds tested, ethylenediamine, hexylamine, hexamethylenediamine and BSA were bound effectively to the dial-CE in this order. As compared with the case of dial-CE, reactions between α-CD dialdehyde (dial-CD) and amino compounds proceeded rather slowly. Separation of dial-CD isomers linked with glycine by a DEAE-Sephacel column resulted in several peaks. However, the components of each fraction were not homogeneous. Reactions of dialdehyde derivatives with amino compounds were thought to produce a 4-oxa-azepine-type of complex.  相似文献   

7.
Catalytic reaction of the 2', 3'-dialdehyde analog of TPN (oTPN) with pig heart TPN-dependent isocitrate dehydrogenase in the presence of the substrate manganous isocitrate results in the formation of the dialdehyde derivative of TPNH (oTPNH). In the absence of the substrate, modification by oTPN leads to a progressive inactivation of the enzyme. The dependence of the pseudo-first order rate constants on the reagent concentration indicates the formation of a reversible complex with the enzyme prior to covalent modification (kmax = 5.5 X 10(-2) min-1; K1 = 290 microM). Reaction of [14C]oTPN with the enzyme results in the incorporation of 2 mol of oTPN/mol of peptide chain. No appreciable protection against either inactivation or incorporation by the natural ligands TPN and TPNH was obtained, suggesting different modes of binding of the analog in the presence and absence of the substrate isocitrate. Enzymatically synthesized oTPNH has been isolated and demonstrated to act as an affinity label for a TPNH-binding site of isocitrate dehydrogenase. The inactivation process exhibits saturation kinetics (kmax = 2.67 X 10(-3) min-1; K1 = 33 microM). Protection against activity loss, as well as a decrease in incorporation from 2 to 1 eq of [14C]oTPNH bound/peptide chain was observed in the presence of 1 mM TPNH. From the TPNH concentration dependence of the inactivation rate by oTPNH, a dissociation constant of 3.4 microM is calculated for TPNH, indicating binding of the analog to a specific TPNH-binding site on the enzyme. Although dialdehyde derivatives are frequently assumed to form Schiff bases with proteins, the evidence presented suggests the formation of morpholino derivatives as the products of the covalent reaction of isocitrate dehydrogenase with the dialdehyde derivatives of TPN and TPNH. The new reagent, oTPNH, may serve as an affinity label for other dehydrogenases.  相似文献   

8.
Periodate-oxidized ADP, if left in aqueous solution, loses its phosphates by beta-elimination. This dephosphorylated dialdehyde compound caused rapid and irreversible inhibition of membrane-bound spinach chloroplast coupling factor 1 (CF1). Inhibition was 2.5 times faster in the light than in the dark. A high concentration of uncoupler eliminated the light stimulation. Light could be replaced by an acid-base transition. Therefore, the dialdehyde reacts with a site or sites on CF1 that become exposed by a high-energy state-induced conformational change. The substrate nucleotides ADP, ATP, GDP, and GTP protected against inhibition while Pi and the non-substrate nucleotides AMP, GMP, CTP, and UTP did not. The protection by GTP was competitive and magnesium-dependent, suggesting that the dialdehyde binds to a nucleotide-binding site. However, the corresponding UDP and CDP dialdehyde derivatives also inhibited CF1 and showed the light-stimulation effect, indicating that the adenine is not important for the binding. These derivatives could be binding to a nucleotide-binding site or to another reactive site that becomes exposed during the light-induced conformational change. In the latter case the protection by substrate nucleotides would be due to prevention of the energy-dependent conformational change.  相似文献   

9.
A procedure for the conversion of reducing oligosaccharides into their 1,5-anhydroalditol derivatives was devised to prevent overoxidation during periodate oxidation. Gas-chromatographic analysis of the aldehydes in the products of complete oxidation of the resultant 1,5-anhydroalditol derivatives by the dithioacetal method1b indicated that new types of dialdehyde characteristic of the linkage-types were formed, together with ordinary simple aldehydes. A number of d-gluco-oligosaccharides having various types of interglycosidic linkage were examined by this method. The results were consistent with expectations.  相似文献   

10.
New water-soluble derivatives of starch, pectin, and Na-CMC containing the sulfamic groups have been obtained by the reaction of sulfamic acid with dialdehyde polysaccharide derivatives. The structure and composition of the resulting compounds have been studied by IR spectroscopy, elemental (nitrogen and sulfur) analysis, and X-ray diffraction. The sulfamic derivatives of starch, pectin, and Na-CMC with a different content of the sulfamic groups have been obtained by varying the ratio of sulfamic acid to the dialdehyde polysaccharide derivatives. The optimal–СНО: NH2SO3H ratio was found to be 1: 2.5. The interaction rate of sulfamic acid with the dialdehyde derivatives of starch, pectin, and Na-CMC has been evaluated. The antibacterial and antifungal effects of sodium salts of the sulfamic starch, pectin, and Na-CMC derivatives against Gram-positive and Gram-negative bacteria and fungi have been studied at different concentrations (10, 25, 50 mg/mL) by the disk diffusion method. The synthesized compounds have not been found to exhibit antifungal activity against Candida albicans. Nevertheless, they have been shown to have the antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Proteus vulgaris, Streptococcus faecalis, Streptococcus pyogenes, and Streptococcus faecalis at the concentration of 50 mg/mL. The concentration dependence of antibacterial action of sodium salts of the starch, pectin, and Na-CMC sulfamic derivatives has been demonstrated. The antibacterial activity of the drugs has been found to directly depend on the content of the sulfamic groups in polysaccharides. The results on the acute toxicity of the sulfamic polysaccharide derivatives have shown that these compounds can be attributed to low-toxicity substances of Class V.  相似文献   

11.
Polygodial (1) and its derivatives acetal 2 (propylene) and 3 (ethylene) were prepared and their antifeedant activity and toxic effects evaluated on several insect species with different feeding ecologies (Spodoptera littoralis, Leptinotarsa decemlineata, Myzus persicae and Rhopalosiphum padi) along with that of polygonone (4). We also tested their selective cytotoxic effects on insect-derived (Spodoptera frugiperda ovarian Sf9 cells) and mammalian Chinese hamster ovary (CHO) cells. The antifeedant activity of these compounds was consistent with the proposed mode of action for antifeedant drimanes, i. e. adduct formation with amino groups for M. persicae and R. padi (dialdehyde > ketoaldehyde > aldehydeacetal). This was not the case for L. decemlineata, and the cytotoxic effects on insect-derived Sf9 and mammalian CHO cells (aldehydeacetal > dialdehyde > ketoaldehyde).  相似文献   

12.
Acid-catalyzed hydrolysis was used as the mechanism to design a new type of environmentally sensitive fluorescence probe. A mild and selective periodate oxidation of the 2-amino alcohol of serine in the presence of a disulfide bond was developed to prepare dialdehyde peptides. Two identical fluorochrome hydrazide derivatives were then linked to the dialdehyde peptide forming an acid-labile hydrazone linkage. This self-quenched probe is weakly fluorescent at a physiological pH of 7.4 but shows more than 3-fold fluorescence enhancement at pH 4.5.  相似文献   

13.
(1) Periodate oxidation of ATP yields a single product which has been purified and characterised. Periodate-oxidised ATP (o-ATP) behaves as a single compound during TLC analysis, but NMR spectral studies show that it exists in aqueous solution as an equilibrium mixture of three dialdehyde monohydrates and a dihydrate. Little free aldehyde is present. The dialdehyde monohydrates are in the form of diastereomeric cyclic hemiacetals. (2) The dialdehyde grouping of o-ATP can be reduced with sodium borohydride, producing a dialcohol. (3) o-ATP has been frequently used in attempts to affinity label nucleotide-binding sites on proteins. The proposed structure of o-ATP is discussed in relation to this use for o-ATP.  相似文献   

14.
Products of the reaction between dialdehyde starch and Y-NH2 compounds (e.g. semicarbazide or hydrazine) are effective ligands for metal ions. The usefulness of these derivatives was tested in the experiment, both in terms of the immobilization of heavy metal ions in soil and the potential application in phytoextraction processes. The experimental model comprised maize and the ions of such metals as: Zn(II), Pb(II), Cu(II), Cd(II), and Ni(II). The amount of maize yield, as well as heavy metal content and uptake by the aboveground parts and roots of maize, were studied during a three-year pot experiment. The results of the study indicate the significant impact of heavy metals on reduced yield and increased heavy metal content in maize. Soil-applied dialdehyde starch derivatives resulted in lower yields, particularly disemicarbazone (DASS), but in heavy metal-contaminated soils they largely limited the negative impact of these metals both on yielding and heavy metal content in plants, particularly dihydrazone (DASH). It was demonstrated that the application of dihydrazone (DASH) to a soil polluted with heavy metals boosted the uptake of Zn, Pb, Cu, and Cd from the soil, hence there is a possibility to use this compound in the phytoextraction of these metals from the soil. Decreased Ni uptake was also determined, hence the possibility of using this compound in the immobilization of this metal. The study showed that dialdehyde starch disemicarbazone was ineffective in the discussed processes.  相似文献   

15.
16.
A study was made of the influence of rheopolyglucin and dextran dialdehyde derived therefrom on the structural characteristics and thermostability of human hemoglobin. The effects of solution pH, incubation time and temperature, and the degree of dextran oxidation on the conjugation between human hemoglobin and dextran dialdehyde were assessed. Formation of the hemoglobin-dextran dialdehyde complex resulted in shielding of the protein chromophore groups by the polysaccharide and transition of a part of hemoprotein molecules from a low-spin (HbO2) to a high-spin (Hb and MetHb) state. It was found that the temperature of denaturation transition for the native protein and hemoglobin in the presence of rheopolyglucin was 60°C versus 80°C for the hemoprotein-dextran dialdehyde conjugate. Presumably, the latter is determined by the enhancement of hydrophobic interactions within the protein globule caused by dextran dialdehyde and the ability of the surface-bound carbohydrate components to prevent the association of hemoglobin molecules.  相似文献   

17.
A simple and sensitive assay method for glucanase activity was established using fluorescent polysaccharide substrates. Periodate oxidized α-glucans having dialdehyde were covalently attached to the fluorescent reagent via Schiff base formation followed by NaBH4 reduction. Ethylenediaminonaphthalene (EDAN) was effective to produce a stable and highly fluorescent polysaccharide. EDAN derivatives of glycogen and dextran dialdehyde were useful substrates for Taka-amylase A and endodextranase, respectively. Two cellulases were shown to release water-soluble fluorescent products from the EDAN derivative of cellulose powder. Moreover, the action of the exo type of enzyme such as glucoamylase was readily distinguished from that of the endo type of enzyme because the attached EDAN prevented the attack of exo-enzyme.  相似文献   

18.
The present study investigates the antimicrobial activity of oxidized schizophyllan (scleraldehyde) against Gram-positive and Gram-negative bacteria by diffusion and tube dilution analysis. Schizophyllan is a natural polysaccharide produced by fungi of the genus Schizophyllum. Periodate oxidation specifically cleaves the vicinal glycols in scleraldehyde to form their dialdehyde derivatives. The antibacterial activity exhibited by scleraldehyde was defined using various tests such as the disc diffusion assay, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). MIC and MBC values were found to be in the range of 3.0-8.0 mg/mL. Hence, the present studies establish that the scleraldehyde possesses effective antibacterial properties and can be used as a biopreservative for preservation of raw hides and skins.  相似文献   

19.
In experiments with V-79 Chinese hamster cell culture the influence of dextran gammaphos derivatives on the mutagenic effects of gamma-radiation was studied by the number of cells with micronuclei and fragmented nuclei. Products of interaction between gammaphos and dialdehyde dextran were shown to have a higher antimutagenic activity than gammaphos.  相似文献   

20.
The thermostabilization of penicillin G acylase (PGA) obtained from a mutant of Escherichia coli ATCC 11105 by cross-linking with dextran dialdehyde molecules, at a molecular mass of 11 500, 37 700 and 71 000 Da, was studied. The thermal inactivation mechanisms of the native and modified PGA were both considered to obey first-order inactivation kinetics during prolonged heat treatment, forming fully active but temperature-sensitive transient states. The highest enhancement to the thermostability of PGA was obtained using dextran-71000-dialdehyde modification, as a␣nearly ninefold increase at temperatures above 50 °C. The modification of PGA by dextran-11500-dialdehyde resulted in a considerable reduction of the V m and K m parameters of the enzyme. However, other dextran dialdehyde derivatives used for modification did not cause a meaningful change in either V m and K m. Modification by dextran dialdehyde derivatives did not result in significant change to either the optimal temperature or the activation energy of PGA. All modified PGA preparations showed lower inactivation rate constants but higher half-lives for inactivation than those of the native PGA at all temperatures studied. As indicated by the half-life times and k i values, dextran 71000-dialdehyde was found to be more effective at cross-linking in the thermo-stabilization of PGA than any other agent studied in this work. Received: 3 December 1996 / Received revision: 17 March 1997 / Accepted: 22 March 1997  相似文献   

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