Determined by analysis of the gem-dimethyl region in the'H NMR of the crude reaction mixture. These values are consistent with the isolated product yields. Prepared by treatment of the corresponding glycine ester derivatives with thiophosgene." Prepared by the treatment ofN-[[(ethoxycarbonyl) thio]-thioxomethyl] glycine1* with TEA (1 equiv) followed by chloromethyl methyl ether (1 equiv). The glycine esters required for making these ...