An efficient, catalyst free, 1,3-dipolar cycloaddition strategy to conjugate nucleosides and nucleotides with isoxazoles under atmospheric conditions and in an aqueous environment is reported. The protocol involves chloramine-T as a practical reagent to induce in situ nitrile oxide formation and the alkyne partner is attached to the sugar residue or the nucleobase. The reactions are regiospecif...

In this method of labeling thyroliberin for radioimmunoassay, 1,3,4,6-tetrachloro-3a,6a-diphenylglycoluril (lodogert#{174}) is usedas oxidant. By cation-exchange chromatography and in response to antibody, thyroliberin so labeled behaved similarly to that produced by the conventional Chloramine-T method. Major advantages of the lodogen method are its reliability, simplicity, and higher yield of...

The model hydrogen peroxide-myeloperoxidase-chloride system is capable of generating the powerful oxidant hypochlorous acid, which can be quantitated by trapping the generated species with the beta-amino acid, taurine. The resultant stable product, taurine chloramine, can be quantitated by its ability to oxidize the sulfhydryl compound, 5-thio-2-nitro-benzoic acid to the disulfide, 5,5'-dithiob...

Doctor fish (Garra rufa) have recently been used for aesthetic purposes and as a medical treatment in patients with psoriasis (ichthyotherapy). For this particular kind of human therapy it is essential to guarantee adequate hygienic conditions for both people and fish. The aim of this study was to test two concentrations of water disinfectants, chloramine T and peracetic acid, on Garra rufa to ...

A crude hCG with an activity of about 3,000 IU per mg was purifed to 10,000--15,000 IU per mg of dry weight using Amberlite CG-50 chromatography combined with DEAE-Sephadex A-50 and Sephadex G-75. The alpha and beta subunits of hCG were prepared by urea-treatment of the hormone and isolated by DEAE-Sephadex A-50 chromatography. Further purification of the subunits was achieved by gel filtration...

Environmentally benign HPA is found to be an efficient catalyst for aziridination of olefins in the presence of inexpensive Chloramine-T as a nitrogen source: instantaneous at room temperature, requires only stoichiometric amount of olefin and no allyl amine side product.

Aldehyde phenyl hydrazones 2a-i undergo oxidative dehydrogenation with Chloramine-T to give nitrile imines, which are trapped in situ by ethyl oleate 1 to afford 8-(5-Aryl-4-octyl-2-phenyl-3,4-dihydro-2Hpyrazol-3-yl)-octanoic acid ethyl esters 3a-i in good yield. The structures of the cycloadducts were confirmed by spectral studies and elemental analysis.

The stereoselective aziridination of a range of cyclic allylic alcohols using two different chloramine salts (4-MeC(6)H(4)SO(2)NClNa, TsNClNa and t-BuSO(2)NClNa, BusNClNa) has been explored. The stereoselectivity of these reactions was highly dependent on the structure of the allylic alcohol and the chloramine salt. Generally, mixtures of cis- and trans-hydroxy aziridines were obtained, in whic...

Tuning the ratio of complementary biocidal groups in a composite unit is proved to be tactic better minimize their weaknesses realize higher synergism. A silane with precursors one pyridinium and two N-chloramine sites, 6-(pyridin-4-yl)-3-(3-(trimethoxysilyl)propyl)-1,3,5-triazinane-2,4-dione, was synthesized, hydrolyzed dehydrocondensed into silicone modifier on cotton cellulose. Specially, is...

The reaction of free chlorine with tertiary ammonium or amine compounds in aqueous solution was studied by the amperometry at a rotating Pt-disk electrode. The amperometric method can be applied to follow the concentration of free chlorine (c(Cl)) even in the presence of chloramine species. By addition of mono- and dibutylammonium to the solution containing free chlorine, the step-like decrease...