55154-30-8

The 3,4-dichloro-N-(1-(dimethylamino)cyclohexyl)methyl benzamide scaffold was studied as a template for 18F-positron emission tomography (18F-PET) radiotracer development emphasizing sensitivity to changes in opioid receptor (OR) occupancy over high affinity. Agonist potency, binding affinity, and relevant pharmacological parameters of 15 candidates were investigated. Two promising compounds 3b and 3e with μ-OR (MOR) selective agonist activity in the moderate range (EC50 = 1-100 nM) were subjected to 18F-fluorination, autoradiography, and small-animal PET imaging. Radioligands [18F]3b and [18F]3e were obtained in activity yields of 21 ± 5 and 23 ± 4% and molar activities of 25-40 and 200-300 GBq/μmol, respectively. Displaceable binding matching MOR distribution in the brain was confirmed by imaging. Radioligands showed a rapid pharmacokinetic profile; however, metabolite-corrected, blood-based modeling was required for data analysis. Observed BPND was low, although treatment with naloxone leads to a marked decrease in specific binding, confirming the discovery of a new template for 18F-labeled OR-agonist PET ligands.

Opioids are powerful analgesics acting via the human μ-opiate receptor (hMOR). Opioid use is associated with adverse effects such as tolerance, addiction, respiratory depression, and constipation. Two synthetic opioids, AH-7921 and U-47700 that were developed in the 1970s but never marketed, have recently appeared on the illegal drug market and in forensic toxicology reports. These agents were initially characterized for their analgesic activity in rodents; however, their pharmacology at hMOR has not been delineated. Thus, we synthesized over 50 chemical analogs based on core AH-7921 and U-47700 structures to assess for their ability to couple to Gαi signaling and induce hMOR internalization. For both the AH-7921 and U-47700 analogs, the 3,4-dichlorobenzoyl substituents were the most potent with comparable EC50 values for inhibition of cAMP accumulation; 26.49?±?11.2?nmol L?1 and 8.8?±?4.9?nmol L?1, respectively. Despite similar potencies for Gαi coupling, these two compounds had strikingly different hMOR internalization efficacies: U-47700 (10?μmol L?1) induced ~25% hMOR internalization similar to DAMGO while AH-7921 (10?μmol L?1) induced ~5% hMOR internalization similar to morphine. In addition, the R, R enantiomer of U-47700 is significantly more potent than the S, S enantiomer at hMOR. In conclusion, these data suggest that U-47700 and AH-7921 analogs have high analgesic potential in humans, but with divergent receptor internalization profiles, suggesting that they may exhibit differences in clinical utility or abuse potential.

Antibodies, immunoassay methods and kits for the detection and determination of 3,4,-dichloro-N-[(1-(dimethylamino)cyclohexyl)methyl]benzamide and 3,4,-dichloro-N-[(1-(methylamino)cyclohexyl)methyl]benzamide, as well as the precursory immunogens, are described.

Compounds of the general formula I: EQU1 in which R1 - R4 which may be the same or different represent hydrogen atoms, or C1-6 straight or branched chain alkyl, alkenyl or alkynyl group or an alkyl group substituted by a cycloalkyl group, or represents a cycloalkyl, alkoxycarbonyl, aryl, arakyl, acyl (which includes anylsulphonyl) groups in which the alkyl group or the alkyl portion of the aralkyl group may be substituted with one or more hydroxy or esterified hydroxy groups and in which the aryl groups or the aryl portion of the acyl or aralkyl group may be substituted by one or more halogen atoms, alkyl groups, hydroxy groups, alkoxy groups, trifluoromethyl, nitro, amino or dialkylamino groups, and in which R5 - R8 which may be the same or different represent hydrogen atoms or alkyl groups except that not all groups may be hydrogen, or R5 and R6 or R7 and R8 together represent a carbonyl (=O) oxygen and in any of the pairs of groups R1 /R2, R3 /R4, R5 /R6 and R7 /R8 may represent a carbocyclic or heterocyclic ring system optionally substituted by lower alkyl or aryl groups, said ring being saturated or unsaturated. These compounds have utility as oral analgesics.