PURPOSE: To obtain a novel pyrrole derivative useful as an intermediate for synthesizing a texaphyrin metal complex useful as an internal diagnostic, and enabling to safely produce the metal complex in a short process.

CONSTITUTION: This compound is expressed by formula I (R1 is H, 1-4C alkyl, 7-10C aralkyl; R2 is H, 1-4C alkyl), e.g. 5-acetyloxymethyl-4-(3-acetyloxypropyl)-3- methylpyrrole-2-carboxylic acid benzyl ester. The compound is obtained by reacting a 4-(3-acyloxypropyl)-3,5-dimethylpyrrole-2-carboxylic acid ester of formula II with lead tetraacetate in acetic acid solvent or with a halogenating agent in the presence of an acetate salt. The compound of formula I can be reacted with 3,4-diethylpyrrole and, if necessary, subsequently reduced or acylated to give a compound of formula III (R3 is H, benzyl; R4 is H, acetyl) which is a synthetic intermediate for the texaphyrin metal complex.