| 摘要 |
<p>Pyrimidine derivs. of formula (I) and their salts with metals, NH4 or amines are new. In (I), Tet is 1H-tetrazol-5-yl; X is N or CR3; Y is S or NH; when it is S, then X is CR3; Z is O, S or NH; R2 and R3 are H or A, or together complete 5-7 membered cycloalkenyl or benzo, each with 0-2 A substits.; A is alkyl, alkenyl, alkynyl, alkoxy, alkenoxy, alkanoyl, alkenoyl, alkylsulphonyl, alkylsulphinyl, alkylthio, alkanamido, 3-7C cycloalkyl or 3-7C cycloalkyl-alkyl (both opt. with 1-3C alkyl substits.), all these gps. have 8C; phenyl, benzyl, CF3, NO2, NH2, OH, CONH2, CN, 2-4C cyanoalkyl or halo. (I) are antiallergens useful e.g. in prophylaxis of asthma, and some are also bronchodilators. The cpd. 3-(1H-tetrazol-5-yl)-4H-pyrimido(2,1-b)benzothiazol-4-one (Ia) has oral LD50 (rat) about 2-5 g./kg. and oral ED50 in the passive cutaneous anaphylaxis test 0.064 mg./kg.</p> |
