3,9-Diazabicyclo[3.3.1]nonane derivatives with analgesic activity

Compounds of formula 1:

• 29
• wherein
• R is a group of formula
• 30
• wherein
• B is a C6-C10 aryl group, optionally substituted at the ortho-, meta- or para-positions with one or more substituents, which are the same or different, selected from the group consisting of C1-C3 alkoxy, C1-C2 halo alkyl, C1-C3 alkyl, halogens, carboxy, cyano, nitro;
• a C5-C7 cycloalkyl group, a 5 or 6 membered heterocyclic aromatic group, optionally benzofused, having at least one heteroatom selected from nitrogen, oxygen, sulfur;
• said heterocyclic group optionally having one or more substituents as described above for the aryl group;
• R2 is hydrogen, C1-C4 alkyl, C5-C7 cycloalkyl or a phenyl group optionally substituted as indicated above;
• R1 is a straight or branched C2-C8 acyl group
• and the pharmaceutically acceptable salts thereof