Patent ID: 7648995

Claim:
A compound selected from R(−)-10-methyl-11-O-acetyl-N-n-propyl-noraporphine, R(−)-10-methyl-11-O-propionyl-N-n-propyl-noraporphine, R(−)-10-methyl-11-O-isobutyryl-N-n-propyl-noraporphine, R(−)-10-methyl-11-O-butyryl-N-n-propyl-noraporphine, R(−)-10-methyl-11-O-isovaleryl-N-n-propyl-noraporphine, R(−)-10-methyl-11-O-valeryl-N-n-propyl-noraporphine, and pharmaceutically acceptable salts thereof.