A compound of the formula
wherein R1 is a hydrogen atom or a lower alkyl group which may be substituted with hydroxy, lower alkyl or di-lower alkylamino; R2 is a hydrogen atom, an amino group or a lower alkylamino group; and R3 is a lower alkyl group, and a nontoxic salt thereof, and a process for preparing the same are disclosed.
The compound and the salts thereof exhibit antiallergic effects by the two different mechanisms and are expected to be useful as drugs for treating allergic diseases such as asthma, pollen allergy, atopic dermatitis and the like.
式中的化合物
其中 R1 是氢原子或可被羟基、低级烷基或二低级烷基
氨基取代的低级烷基;R2 是氢原子、
氨基或低级烷基
氨基;R3 是低级烷基,本发明公开了其无毒盐及其制备方法。
该化合物及其盐通过两种不同的机制表现出抗过敏作用,有望成为治疗哮喘、花粉过敏、特应性皮炎等过敏性疾病的有用药物。