Abstract: A fused pyrimidine derivative is presented. The derivatie has an insulin secretion stimulating activity represented by Formula (I): {wherein R1 represents a hydrogen atom, lower alkyl, or the like; n represents an integer of 0 to 3; and X1 and X2 may be the same or different and each represents a hydrogen atom, lower alkyl, or the like; and formula (II): represents formula (III): [wherein X—Y—Z represents R2C?CR3—NR4 (wherein R2, R3 and R4 may be the same or different and each represents a hydrogen atom, lower alkyl, or the like)]}, or a pharmaceutically acceptable salt thereof.

Abstract: The present invention provides a compound represented by formula (I): [wherein X—Y-Z represents R5N—C?O (wherein R5 represents a hydrogen atom, substituted or unsubstituted lower alkyl, substituted or unsubstituted aralkyl, substituted or unsubstituted lower alkenyl, or substituted or unsubstituted lower alkynyl), etc; R1 and R2 may be the same or different and each represents a hydrogen atom, substituted or unsubstituted lower alkyl, etc; and R3 and R4 may be the same or different and each represents a hydrogen atom, substituted or unsubstituted lower alkyl, etc], or a pharmaceutically acceptable salt thereof.

Abstract: A condensed purine derivative represented by Formula (I): wherein X—Y-Z represents R1N—C?O or N?C—W, R2 represents a hydrogen atom, a substituted or unsubstituted lower alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted alicyclic heterocyclic group or the like, n represents an integer of from 0 to 3, V1 represents a hydrogen atom, a substituted or unsubstituted lower alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aromatic heterocyclic group, V2 represents a substituted lower alkyl group or a substituted or unsubstituted aromatic heterocyclic group, and when V1 represents a hydrogen atom, a lower alkyl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted aryl group, and for example, X—Y-Z represents R1aN—C?O and R2 represents a substituted lower

Abstract: A condensed purine derivative represented by Formula (I): 1

Abstract: A medicament for the therapeutic treatment of diabetes which comprises as an active ingredient a compound represented by the general formula (I): wherein R1 represents a hydrogen atom, a lower alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aromatic heterocyclic group, R2 represents a hydrogen atom, a lower alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aromatic heterocyclic group, R3 represents a hydrogen atom, a lower alkyl group or a substituted or unsubstituted aralkyl group, X1 and X2 independently represent a hydrogen atom, a lower alkyl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted aryl group, and the symbol “n” represents an integer of from 0 to 3, or a physiologically acceptable salt thereof.