Anellated dihydropyridines for the treatment of chronic pain

1) A method of treating chronic pain comprising administering to a host in need of such treatment a compound of the following formula I or a salt thereof with a physiologically acceptable acid:

• 37
• wherein A is benzo or thieno,
• and if A is benzo
• R1, R2 and R3 independently of one another denote
• H, OH,C1-C5 alkyl, C1-C5 alkoxy, or —O—(CH2)1-5—OCH3,
• or R2 and R3 together form the group
• —O—CH2—O—, and
• if A is thieno, R1, R2 and R3 denote hydrogen;
• R4 and R5 independently of one another denote
• H, or C1-C5 alkyl or together with the atom to which they are bonded form a C3-C7 ring;
• R6 denotes C1-C12 alkyl, or denotes a phenyl or benzyl group each substituted by the groups R7and R8,
• wherein R7 and R8 independently of one another denote hydrogen, halogen, C1-C5 alkyl, C1-C5 alkoxy or C1-C5 fluoroalkyl group;
• Z denotes O, S or an NHCO— group or, if at least one of the groups R4 and R5 is other than hydrogen, Z may also denote a single bond.