The compounds of formula (1), in which R1, R7, R8, R9, R10, R17, R18, R19, R20 and m have the meanings as given in the description, are novel effective inhibitors of type 4 and 5 phosphodiesterase.
式(1)中的化合物,其中R1、R7、R8、R9、R10、R17、R18、R19、R20和m的含义如描述中所述,是新颖的有效的4型和5型
磷酸二酯酶抑制剂。