| 摘要 |
<p>Compounds of the formula (I):- <CHEM> and pharmaceutically acceptable salts thereof, wherein R<1> and R<2> are independently hydrogen or C1-6 alkyl, or R<1>R<2>N represents 2,2,2,-trifluoroethylamino; or R<1> and R<2> form a -(CH2)n- linkage, wherein n is 4-6, so that together with the nitrogen atom to which they are attached they form a 5-7 membered ring; and R<3> is hydrogen or C1-6 alkyl, are described. Processes for their preparation involving inter alia novel intermediates, pharmaceutical compositions containing them and their use as histamine antagonists are described also.</p> |
