In the present study a series of 1-substituted-4-(3-chlorophenyl)-[1,2,4] triazolo [4,3-a] quinazolin-5(4H)-ones were synthesized and screened for their H1-antihistaminic activity. The synthesized compounds were characterized by IR, 1H-NMR, mass spectral data and purity of the compounds was dete...

Excess piperidine and 2-chloro-7-nitroquinoxaline 1 in diethyl ether give large amounts of the unexpected disubstitution product 6-nitro-2,3-di-piperidinoquinoxaline 3. The mechanism of this very unusual nucleophilic substitution of hydrogen is suggested to involve the oxidation of the dipiperid...

A practical and environmentally friendly synthesis of 3-aminomethyl-N-tosyl-indazoles is developed. The in situ formed vinyl azines are reacted with amines to furnish amino functionalized anti-hydrazones in excellent yields. Subsequent copper-catalyzed cyclization at ambient temperature is effec...

A series of quinoline containing receptors having amide and ester bonds are synthesized and characterised. The relative binding abilities of these receptors with various amino acids, carboxylic acids and mineral acids are determined by monitoring the changes in fluorescence intensity. Among the ...

Background: Yew species (Taxus spp.) throughout the world are hosts to hundreds, or perhaps thousands, of endophytic organisms. Most commonly, these organisms are fungi, living in a commensal or a symbiotic relationship with their host plant, so the plants exhibit little or no outward evidence t...

Ras farnesylation by farnesyl protein transferase (FPT) is an intracellular event that facilitates the membrane association of the ras protein and is involved in the signal transduction process. FPT inhibition could be a novel, noncytotoxic method of treating ras dependent tumor growth. We repor...

The system composed of manganese (2,6)-dichlorotetraphenyl- or pentafluorotetraphenyl-porphyrins, bearing nitro groups at the β-pyrrolic positions as catalysts and monoperoxyphthalic acid magnesium salt (MMPP) as oxidant is an efficient model system for epoxidation of dodecene-1 and propene. A ...

N-Methylfurohydroxamic acid (N-MFHA) has been syntehsized and shown to be an excellent chelating reagent for a number of metal ions. Considerable selectivity is achieved by pH adjustment. Metal ions can be separated into groups or concentrated from very dilute solutions by complexation with N-MF...

Hirudin PA54–66 and related hirudin fragment analogs were synthesized and assessed for their inhibition of thrombin-induced fibrin-clot formation in plasma. Pro58 and Ala63 -Tyr64 modifications in the hirudin sequence resulted in increased antithrombin potency, whereas Asp, Ala and Tyr individu...

The structure of a recombinant hirudin (variant 2, Lys47) human α-thrombin complex has been refined using restrained least-squares methods to a crystallographic R-factor of 0·173. The hirudin structure consists of an N-terminal domain folded into a globular unit and a long 17-peptide C-termina...

Sulfation of tyrosine residues is a common post-translational modification, but detecting and quantitating this modification poses challenges due to lability of the sulfate group. The goal of our studies was to determine how best to detect and to assess the stoichiometry of this modification usi...

rDNA hirudin plasma concentrations in man and rhesus monkeys were determined over a period of 15 and 24 h. The plasma concentration of α-human thrombin-hirudin complex was measured after administration of the complex to rhesus monkeys. The complex was also determined after administration of hir...

To express recombinant hirudins in Escherichia coli cells, a fragment of chemically synthesized DNA was used, containing codons for the individual amino acids preferred by the host cells. Gene synthesis was based on the design of two DNA fragments, so-called mega primers H1 and H2 with a complem...

Components of the blood have been proposed as potential therapeutic targets for improving cellular regeneration after injury and neurodegenerative disease. In this work, thrombin is shown to increase endogenous neural progenitor proliferation in the intact murine spinal cord. A local injection o...

Publisher SummaryThis chapter describes the hirudin and hirudin-based peptides. Hirudin and hirudin-based peptides have served as exemplary tools for the studies on thrombin structure-function relationships and on thrombin biological activities. Binding of hirudin and peptide fragments with thro...

Collision-induced dissociation (CID) was performed on multiply deprotonated ions from three commercial peptides: hirudin (54–65), fibrinopeptide B, and oxidized insulin chain A. Ions were produced by electrospray ionization in a Fourier transform ion cyclotron resonance mass spectrometer. Each ...

Hirudin is the most anticoagulant drug found in nature, but its short serum half-life significantly inhibits its clinical application. The PEGylation of hirudin, the most promising anticoagulant drug, was performed in this paper. The optimal reaction conditions for PEGylated hirudin were investi...

Hematopoietic progenitors from murine fetal liver efficiently differentiate in culture into proplatelet-producing megakaryocytes and have proved valuable to study platelet biogenesis. In contrast, megakaryocyte maturation is far less efficient in cultured bone marrow progenitors, which hampers s...

The syntheses of all four possible diastereomers of 9-(1,3,4-trihydroxy-2-butoxymethyl)guanine, starting from D- and L-xylose and from D- and L-arabinose derivatives are described.

The photochemical behavior of etodolac was investigated under various irradiation conditions. Kinetic data were obtained after irradiation of 10− 4 M aqueous solutions by UVB, UVA and direct exposure to sunlight. The Xenon lamp irradiation was used in order to determine the photodegradation quan...