| abstract |
A compound represented by general formula (I) or a pharmaceutically acceptable salt or ester thereof: [wherein each of Ar 1 , Ar 2 , Ar 3 and Ar 4 is an aryl group or an aromatic heterocyclic group; A 1 is a C 2-6 chain hydrocarbon group or a group represented by --A 1a --W 1 --A 1b -- (wherein W 1 is an oxygen atom, a sulfur atom, an ethynylene group, a cyclopropylene group or a group represented by --NR W --; A 2 is a C 2-8 chain hydrocarbon group; each of X and Y is an oxygen atom, a sulfur atom, a carbonyl group or a group represented by --CHR a -- or by --NR b --, or X and Y together represent a vinylene group or an ethynylene group; each of R 1 , R 2 , R 3 , R 7 and R 8 is a hydrogen atom, a halogen atom, a hydroxyl group, a lower alkyl group, a lower alkenyl group or a lower alkoxy group; each of R 4 and R 5 is a hydrogen atom, a halogen atom, a hydroxyl group, an amino group, a nitro group, a cyano group, a carboxyl group, a lower alkoxycarbonyl group, a carbamoyl group, a lower alkylcarbamoyl group, a lower alkyl group, a lower hydroxyalkyl group, a lower fluoroalkyl group or a lower alkoxy group; and R 6 is a lower alkyl group, provided that when one of X and Y is an oxygen atom, a sulfur atom or a group represented by --NR b --, the other is a carbonyl group or a group represented by --CHR a -- and an antitumor agent comprising it as an active ingredient. |