abstract |
Novel trisubstituted piperazine compounds of the formula (I) and pharmaceutically acceptable salts thereof: ##STR1## wherein R 1 , R 2 and R 3 are lower alkyl groups; A is a phenyl group, a hydrocarbon group formed by condensation of two or three 5- to 8-membered rings, a monocyclic 5- to 8-membered heterocyclic group containing 1 to 3 hetero-atoms selected from the class consisting of nitrogen, oxygen and sulfur, a dicyclic heterocyclic group formed by condensation of a benzene ring with a 5- to 8-membered hetero-ring containing 1 to 3 hetero-atoms selected from the class consisting of nitrogen, oxygen and sulfur, a tricyclic heterocyclic group formed by condensation of (i) a 5- to 8-membered hetero-ring containing 1 to 3 hetero-atoms selected from the class consisting of nitrogen, oxygen and sulfur, and (ii) a benzene ring, and (iii) a benzene ring or a 5- to 8-membered hetero-ring containing 1 to 3 hetero-atoms selected from the class consisting of nitrogen, oxygen and sulfur, or a styryl group of the formula: Ar--CR 4 ═CR 5 -- wherein Ar is a phenyl group, and R 4 and R 5 are independently hydrogen or a lower alkyl group, the phenyl group represented by A or Ar, the hydrocarbon group represented by A, the monocyclic 5- to 8-membered heterocyclic group represented by A, the dicyclic heterocyclic group represented by A and the tricyclic heterocyclic group represented by A being unsubstituted or substituted by one or more substituents selected from the class consisting of a lower alkyl group, a halo lower alkyl group, a hydroxy lower alkyl group, an acyloxy lower alkyl group, a lower alkoxy lower alkyl group, a lower alkoxy group, a halo lower alkoxy group, a lower alkoxycarbonyl lower alkoxy group, a lower alkenyloxy group, aralkyloxy group, a lower alkoxy lower alkoxy group, a lower alkoxycarbonyl group, carboxyl group, carbamoyl group, an N,N-di-lower alkylcarbamoyl group, an N-lower alkylcarbamoyl group, halo group, cyano group, nitro group, hydroxy group, acyloxy group, amino group, a lower alkylsulfonylamino group, acylamino group, a lower alkoxycarbonylamino group, acyl group, mercapto group, a lower alkylthio group, a lower alkylsulfinyl group, a lower alkylsulfonyl group and oxo group; X is methylene group, carbonyl group or thiocarbonyl group and G is a group of the formula: --CH 2 -- n Z--R 6 wherein n is an integer of 0 to 2, Z is a chemical bond, O, S, SO, SO 2 , CO, COO, OCO, OCONR 7 , CONR 7 or NR 7 (wherein R 7 is hydrogen, a lower alkyl group, a lower haloalkyl group, a lower alkenyl group or a lower alkoxycarbonyl group), and R 6 is hydrogen, a lower alkyl group, a lower haloalkyl group or a lower alkenyl group, provided that, when n is O and Z is chemical bond, R 6 is not hydrogen or a lower alkyl group are useful as a platelet activating factor antagonist. |