CHO)(2.1 g, 5.1 mmol), dissolved in 98% formic acid (15 mL), was added at the same temperature and the solution stirred overnight at room temperature. The excess of the oxidant was removed by addition of dimethyl sulfide (3 mL, 41 mmol). The solution was evaporated in vacuo, to give 1.83 g (71%) of L-va-lyltaurine (5b): IR vc-0 1670 cm-'; lH NMR (DMSO-$) 6 4.2 (m, 1 H, NCHCO), 3.2 (m, 2 H), 2.8 (t, 2 H), 1.95 (m, 1 H), 0.9 (m, 6 H); MS ...