p. 1291 - 1294
(1981)benzyl 4-(2-chloro-<<2-13C>ethyl>)-3,5-dimethylpyrrole-2-carboxylate
benzyl 4-(2-chloro-<<1-13C>ethyl>)-3,5-dimethylpyrrole-2-carboxylate
benzyl 4-(2-hydroxy-<<2-13C>ethyl>)-3,5-dimethylpyrrole-2-carboxylate
benzyl 4-<(methoxy-<<13C>carbonyl>)methyl>-3,5-dimethylpyrrole-2-carboxylate