| abstract |
Compounds of formula (I) are described wherein X is, for example,nCH, CH 2, CHR (wherein R is lower alkyl or substitutednlower alkyl) or CRR '(where R and R' are the same as those)nhave been defined for R 1; Y is, for example, CH, CH 2 ornC = O; Z is, for example, O, S, S = O or SO2; Unis C or N; R 1 to R 4 are independently hydrogen,nOR, SR (where R is the same as defined) or aromaticna ring, a substituted aromatic ring or a heterocycle;nat least one of R 5 and R 8 is, for example, hydrogen or OH;ntheir optical isomers, conjugates or pharmaceutically acceptablensalt. These compounds have different pharmacological propertiesneffects such as the relaxation effect on the bronchial smooth muscle,ninhibition of airway hypersensitivity and inhibitionninfiltration of inflammatory cells into the airways, and simultaneouslynhigh security. |