1-Halobenzyl-1H-indazole-3-carboxylic acids. A new class of antispermatogenic agents.

The synthesis of a series of halogenated 1-benzylindazole-3-carboxylic acids and related derivatives is described. These compounds were studied for their effect on testicular weight and on the inhibition of spermatogenesis. Many of the derivatives, but in particular 1-(2,4-dichlorobenzyl)-1H-indazole-3-carboxylic acid (11), 1-(2,4-dibromobenzyl)-1H-indazole-3-carboxylic acid (13), 1-(4-chloro-2-methylbenzyl)-1H-indazole-3-carboxylic acid (27), and their glycerol esters, showed potent antispermatogenic activity.