Convenient synthesis of GOLD and MOLD and identification of their oxidation products in vitro and in vivo.

Two Lys-Lys crosslinks, 1,3-bis-(5-amino-5-carboxypentyl)-1H-imidazolium (GOLD) and 1,3-bis(5-amino-5-carboxypentyl)-4-methyl-1H-imidazolium (MOLD) salts, have been synthesized by the reaction of imidazole or 4(5)-methyl imidazole with 5-(4-bromobutyl)-hydantoin followed by the hydrolysis of 1,3-substituted imidazolium derivatives by 6.0 N HCL at 110 degrees C. Treatment of GOLD and MOLD with hydrogen peroxide in acetic acid leads to MOLD oxidation only. The oxidation product of MOLD was detected in cataractous lens proteins.