Tetrazole compounds as calcium channel blockers

A compound of formula (I), or a salt thereof:

• wherein
• A is
• R1 is hydrogen, methyl or chloro;
• R2 is hydrogen, trifluoromethyl, trifluoromethoxy, chloro or cyano;
• R3 is hydrogen, cyano, trifluoromethyl, trifluoromethoxy, difluoromethoxy, chloro, bromo, —S—CH3, —SO2—C1-3alkyl or —SF5;
• R4 is hydrogen, trifluoromethyl, trifluoromethoxy, chloro or cyano;
• R5 is hydrogen, methyl or chloro;
• wherein at least one of R1, R2, R3, R4 or R5 is a group other than hydrogen;
• X is —CH2—, —CH2—CH2— or —CH(CH3)—;
• wherein when R1 is methyl, R5 is hydrogen or chloro, and when R5 is methyl, R1 is hydrogen or chloro;
• wherein when R2 is chloro, R4 is hydrogen, trifluoromethyl, trifluoromethoxy or cyano, and when R4 is chloro, R2 is hydrogen, trifluoromethyl, trifluoromethoxy or cyano;
• R6 is hydrogen and R7 is C1-5 alkyl or C3-6cycloalkyl;
• or R6 and R7 together with the nitrogen atom to which they are attached form a saturated ring system B, where B is selected from
• a) a 4 to 7 membered monocyclic heterocyclic ring,
• b) a 5 to 10 membered fused bicyclic ring system;
• c) a bridged 4 to 7 membered monocyclic heterocyclic ring system;
• and
• d) a 7 to 11 membered spiro ring system;
• which ring system B is unsubstituted or substituted with 1 to 3 substituents independently selected from halogen, oxo, C1-3alkyl, cyano, —SO2—C1-3alkyl, C1-3haloalkyl and —CO—C1-3alkyl;
• with the proviso that the compound is not 4-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}morpholine, 4-({1-[3-(trifluoromethyl)phenyl]-1H-tetrazol-5-yl}methyl)morpholine hydrochloride, 4-({1-[3-(trifluoromethyl)phenyl]-1H-tetrazol-5-yl}methyl)morpholine, 4-{[1-(3,4-dichlorophenyl)-1H-tetrazol-5-yl]methyl}morpholine, 1-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}-4-(methylsulfonyl)piperazine, 1-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}-4-(propylsulfonyl)piperazine;
• 1-{[1-(3,4-dichlorophenyl)-1H-tetrazol-5-yl]methyl}piperidine;
• 4-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}morpholine;
• 1-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}-4-methylpiperidine;
• 1-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}piperidine;
• 1-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}-4-(ethylsulfonyl)piperazine;
• 1-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}-2-methylpiperidine;
• 1-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}piperazine;
• 1-(4-chlorophenyl)-5-(1-pyrrolidinylmethyl)-1H-tetrazole;
• 1-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}-4-methylpiperazine or 1-{[1-(4-chlorophenyl)-1H-tetrazol-5-yl]methyl}hexahydro-1H-azepine.