Combination of two pharmacophoric systems: synthesis and pharmacological evaluation of spirocyclic pyranopyrazoles with high σ1 receptor affinity.
J Med Chem
; 54(19): 6704-13, 2011 Oct 13.
Article
in En
| MEDLINE
| ID: mdl-21859078
ABSTRACT
The novel class of spirocyclic σ(1) ligands 3 (6',7'-dihydro-1'H-spiro[piperidine-4,4'-pyrano[4,3-c]pyrazoles]) was designed by the combination of the potent σ(1) ligands 1 and 2 in one molecule. Thorough structure affinity relationships were derived by the variation of the substituents in position 1', 1, and 6'. Whereas the small electron rich methylpyrazole heterocycle was less tolerated by the σ(1) receptor protein, the introduction of a phenyl substituent instead of the methyl group led to ligands with a high σ(1) affinity. It is postulated that the additional phenyl substituent occupies a previously unrecognized hydrophobic region of the σ(1) receptor resulting in additional lipophilic interactions. The spirocyclic pyranopyrazoles are very selective against the σ(2) subtype, the PCP binding site of the NMDA receptor, and further targets. Despite high σ(1) affinity, the cyclohexylmethyl derivative 17i (K(i) (σ(1)) = 0.55 nM) and the isopentenyl derivative 17p (K(i) (σ(1)) = 1.6 nM) showed only low antiallodynic activity in the capsaicin assay.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Pyrans
/
Pyrazoles
/
Spiro Compounds
/
Receptors, Opioid, delta
/
Analgesics
Limits:
Animals
Language:
En
Journal:
J Med Chem
Journal subject:
QUIMICA
Year:
2011
Document type:
Article
Affiliation country: