| abstract |
A fused pyrimidine compound having antagonistic activity against a luteinizing hormone-releasing hormone; and a medicine containing the compound. The medicine is a luteinizing hormone-releasing hormone antagonist containing a compound represented by the formula (I) [wherein R1a represents hydrogen or an optionally substituted hydrocarbon group; ring Aa represents an optionally substituted aromatic 6-membered ring; ring Ba represents an optionally substituted homocycle or heterocycle; Wa represents oxygen or sulfur; Xa1 and Xa2 are the same or different and each represents hydrogen, an optionally substituted hydrocarbon group, or an optionally substituted heterocyclic group, provided that Xa1 and Xa2 in combination may form oxygen, sulfur, or NR3a (R3a represents hydrogen or an optionally substituted hydrocarbon group); and Ya represents a bond or optionally substituted C1-6 alkylene], a salt of the compound, or a prodrug of either. |