A compound of formula (I) ** Formula ** in which R 1 is n-propyl, iso-butyl, cyclopropyl, 3-fluorophenyl, 6-chloropyridin-3-yl, 3-chlorophenyl, 4-chlorophenyl, 3-trifluoromethoxyphenyl , 2- (trifluoromethyl) phenyl, 3- (trifluoromethyl) phenyl, 4- (trifluoromethyl) phenyl, 2,6-difluorophenyl, 2,5-difluorophenyl, 3,4-difluorophenyl, 3,5-difluorophenyl, 3-methylphenyl, 4-methylphenyl, 3-methoxyphenyl, 4-methoxyphenyl, 2,3-dichlorophenyl, 1-methylindole or 3-bromophenyl； R2 is -C (O) NR3R4 or R5； one of R3 and R4 is hydrogen, alkyl, cycloalkyl or alkoxyalkyl and the other is - (CH2) n-R6； or R3 and R4, together with the nitrogen atom to which they are attached, form a substituted heterocyclyl or heterocyclyl, wherein the heterocyclyl is piperidinyl, morpholinyl, pyrrolidinyl, 3,4-dihydro-1H-isoquinolinyl, azetidinyl, piperazinyl, 1 , 1-dioxothiomorpholinyl or 2-oxa-8-aza-spiro [4.5] decyl, and wherein the substituted heterocyclyl is heterocyclyl substituted with a substituent selected from halogen, alkyl, cyano, alkoxyalkyl, aminocarbonyl, dialkylaminocarbonyl, dialkylaminocarbonylalkyl, alkylaminocarkylalkyl phenyl, halophenyl, phenyl, halofenilalquilo, methylpyrazolyl, methylisoxazolyl, alkoxyalkyl, alkylcarbonylamino, alkylcarbonyl, alkoxycarbonyl, alkyl- [1,2,4] oxadiazolyl, pirrolidinilcarbonilalquilo, pyrazinyl, (alkyl) (alkylcarbonyl) amino, alquilisoxazolilo and morfolinilcarbonilalquilo or two 20 substituents independently selected from alkyl, halogen, alkoxycarbonyl and alkoxycarbonylamino； R5 is halophenyl alkyl, alkoxycarbonylpiperidinyl, alkoxycarbonylalkyl, (alkylsulfonyl) (alkyl) [1,2,4] triazolylalkyl or morpholinylcarbonylalkyl； provided that 1-Cyclopropyl-4- (pyrrolidin-1-carbonyl) -1,4-dihydro-tetrazol-5-one； 1-Cyclopropyl-4- (2-methyl-pyrrolidin-1-carbonyl) -1,4-dihydro-tetrazol-5-one； 1-Cyclopropyl-4- (2,5-dimethyl-pyrrolidin-1-carbonyl) -1,4-dihydro-tetrazol-5-one； 1-Cyclopropyl-4- (2,6-dimethyl-piperidin-1-carbonyl) -1,4-dihydro-tetrazol-5-one； 4
