Antithyroid substances. 2. Some mercaptoglyoxalines, mercaptothiazoles and thiohydantoins

Abstract
Forty compounds were tested for antithyroid activity as judged by depression of I131 uptake on single dose in rats. A few compounds were also tested for effect of continued feeding on growth rate and thyroid weight and for acute toxicity. 2-Mercapto-1-methylglyoxaline and l-carbethoxy-2_mercaptoglyoxaline showed the highest antithyroid activity. The LD50 of the 3 mercaptoglyoxalines was 180-1400 mg./kg. depending on the route of injn. and derivative used.