A Pyrazolo[1,5-a]Pyrimidine compound.

Abstract

The present invention provides a pyrazolo[1,5-a]pyrimidine compound, having CB receptor-antagonizing activity, of the following formula [I]: in which R1 and R2 are the same or different and each an optionally substituted aryl group etc, R0 is hydrogen atom, an alkyl group etc, E is a group of the formula: -C(=0)- or SO2-, R is a group of the following formula [i], [ii] or [iii] etc: Ring A is (a) a C3-8 cycloalkyl group optionally fused to a benzene ring or (b) a benzene ring, Q is a single bond or a methylene group, Ring B is a 4- to 7-membered aliphatic heterocyclic group, said cyclic group binding via its ring-carbon atom to the adjacent nitrogen atom, X is sulfur atom etc, R3 is an alkyl group optionally substituted by an alkylthio group, R4 is hydrogen atom, an alkyl group etc, one of Ra and Rb is an alkyl group etc, and the other is hydrogen atom, an alkyl group etc.