Patent ID: 7491739

Claim:
A compound represented by the following formula 1 or a salt thereof, wherein A is —(NR 4 )—; B is alkylene or alkenylene; wherein the alkylene and alkenylene is unsubstituted or substituted by hydroxy, alkoxy, cycloalkyl, aryl, siloxy or a saturated or unsaturated heterocycle; R 1 , R 2 and R 4 , being the same or different, are hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, acyl or amino, wherein the alkyl, alkenyl, alkynyl, cycloalkyl or cycloalkenyl are unsubstituted or substituted by halogen, amino, cycloalkyl, adamantyl, aryl, carboxy, alkoxycarbonyl, aryloxycarbonyl, aminocarbonyl, cyano or a saturated or unsaturated heterocycle, said heterocycle being a five to twenty membered heterocycle containing one to four heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur; at least one of R 1 , R 2 , and R 4 is adamantylalkyl, adamantyloxyalkyl, adamantylaminoalkyl or adamantylaminocarbonylalkyl; R 3 is a substituted or unsubstituted pyridine ring; X is O or S; each hydrogen of the aforesaid amino, and aminocarbonyl can be replaced with alkyl, cycloalkyl, adamantyl, adamantylalkyl, aryl, arylalkyl, acyl, alkoxyalkyl, alkoxycarbonyl, alkylaminocarbonyl, cycloalkyloxycarbonyl, arylalkoxycarbonyl, alkylsulfonyl, arylsulfonyl, halogenoalkyloxycarbonyl, imidazolylcarbonyl, pyridylcarbonyl, a saturated or unsaturated heterocycle, or alkyl substituted by a saturated or unsaturated heterocycle, said heterocycle being a five to twenty membered heterocycle containing one to four heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur.