Antithyroid activity of 6-chloropurine was determined, in vitro, by studying its complex formation with iodine spectrophotometrically. The complex exhibited a 1:1 stoichiometry. Formation constant (Kc) of the complex was found to be 7.652 × 10³ L mol-1, which indicated good antithyroid potential of 6-chloropurine. For further verification, changes in the thyroid hormone levels of the male rabbits were observed, in vivo, after administering the dose through intra peritoneal (i.p.) injections for 14 days and measuring free triiodothyronine (T3) and tetraiodothyronine (T4) levels in the blood serum using radioimmunoassay technique. The blood assays showed decrease in free T3 and T4 levels in the treated animals as compared to the control ones thus confirming fairly good antithyroid activity of 6-choloropurine.
6-chloro-9H-purine; iodine; antithyroid activity; charge transfer complex; thyroid hormones
