Tritiated compounds Sodium borohydride

Bu"3SnT) is prepared by the reaction of Bu"3SnLi with tritiated water or by the reaction of Bu"3SnCI with tritiated sodium borohydride. Representative preparations of labeled compounds with a high degree of stereoselectivity are shown in Schemes 16 and 17. ... 

After covalent binding of the inactivator, the enzyme-analog compound is stabilized by reduction of its carbonyl to a carbinol group (Fig. 3). To 100 mg of inactivated enzyme in 0.15 M sodium pyrophosphate (pH 6.0) at 0° are added 10 mg of sodium borohydride. At this pH, formation of dihydro or tetrahydropyridine derivatives could not be observed. Excess sodium borohydride is removed by dialysis. With tritium-labeled sodium borohydride this method yields a tritiated protein complex. 

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