Trinitrobenzenesulfonic acid, reagent

Trimethylaniline lb 268 Trimethyltin chloride lb 319 Trimipramine lb 352,354,355 Trinitrobenzenesulfonic acid, reagent... 

Diazomethane reacts with 2,4,6-trinitrobenzenesulfonic acid with ring opening similar to that observed with 1,3,5-trinitrobenzene.6 Hence an excess of the reagent is to be avoided. The yellow color is not due to the presence of diazomethane itself. The reaction time is highly sensitive to the temperature of the xylene solution and to the flow rate of gaseous dimethyl ether. The reaction time is usually 20-40 minutes. 

Partial regeneration of amino groups takes place on acid hydrolysis. Hence, residual amino groups in the derivative are most readily determined by titration with trinitrobenzenesulfonate ( 3.1.2.3), or by measuring incorporation of labeled reagent. 

Fig. 3. Summary of key experiments examining transbilayer lipid movement in liposomes. Reaction of dithio-bisnitrobenzoic acid (DTNBA) with R-SH gives R-S-SNBA. Each of the experiments was specifically designed to initially sample only the outer leaflet of the bilayer and then at subsequent periods detect the movement of lipid from the inner to the outer leaflet of the bilayer. lAA, isethionylacetimidate TNBS, trinitrobenzenesulfonate DG, diacylglycerol DTNBA, dithiobisnitrobenzoic acid (Ellman s reagent).

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