摘要 |
6-(1H-Tetrazol-5-yl)thiozolo[3,2-a]pyrimidin-5-ones, 3-(1H-tetrazol-5-yl)-4H-pyrimido[2,1-b]benzothiazol-4-ones, and the corresponding imidazo- and triazolo-pyrimidines, thiones, and imines are useful as antiallergy and antiasthmatic compounds by virtue of their inhibitory action on the immediate hypersensitivity reaction in mammals and relaxant action on the tracheal muscle. Intermediates in the synthesis of these substances from 2-aminoazoles and ethoxy-methylene malononitrile also have smooth muscle relaxant and immediate hypersensitivity reaction inhibitory activity. |