DA 4643 (dihydrochloride)

DA 4643 (hydrochloride) is an H2 receptor antagonist with the chemical name 2-guanidino-4 (3-methylaminomethyleneiminophenyl) thiazole dihydrochloride. It has a weak interaction with cytochrome P-450 and has a less inhibitory effect on P-450 than cimetidine and tiotidine. DA 4643 (hydrochloride) is able to inhibit both enzymatic and non-enzymatic lipid peroxidation reactions. This inhibition may not be achieved by inhibiting agent metabolizing enzymes, but rather due to the antioxidant properties of the compound itself. Compared with other H2 receptor antagonists such as cimetidine, ranitidine and tiotidine, DA 4643 (hydrochloride) shows a unique effect in lipid peroxidation inhibition. These properties make DA 4643 (hydrochloride) a potential H2 receptor antagonist with multiple mechanisms of action.