1 0.42 0.24 0.32 2 0.22 0.22 3 0.14 0.20 4 0.19 0.21 0.29 5 0.73 0.34 0.375 5 which was removed during the preparative TLC after iodination. If the product was not to undergo a chromatographic separation, the small amount of 5 could be removed by increasing the volume of HBr to 15.5 ml and the time of hydrolysis to 5.5 h. A second recrystallization of the hydrochloride from 2 N HCl before conversion to the free amino acid was required to ...
