CoMFA analyses of C-2 position salvinorin A analogs at the kappa-opioid receptor provides insights into epimer selectivity. J Mol Graph Model 2010 Apr;28(7):612-25
Date
01/20/2010Pubmed ID
20083418Pubmed Central ID
PMC2859180DOI
10.1016/j.jmgm.2009.12.008Scopus ID
2-s2.0-76549096825 (requires institutional sign-in at Scopus site) 14 CitationsAbstract
The highly potent and kappa-opioid (KOP) receptor-selective hallucinogen Salvinorin A and selected analogs have been analyzed using the 3D quantitative structure-affinity relationship technique Comparative Molecular Field Analysis (CoMFA) in an effort to derive a statistically significant and predictive model of salvinorin affinity at the KOP receptor and to provide additional statistical support for the validity of previously proposed structure-based interaction models. Two CoMFA models of Salvinorin A analogs substituted at the C-2 position are presented. Separate models were developed based on the radioligand used in the kappa-opioid binding assay, [(3)H]diprenorphine or [(125)I]6 beta-iodo-3,14-dihydroxy-17-cyclopropylmethyl-4,5 alpha-epoxymorphinan ([(125)I]IOXY). For each dataset, three methods of alignment were employed: a receptor-docked alignment derived from the structure-based docking algorithm GOLD, another from the ligand-based alignment algorithm FlexS, and a rigid realignment of the poses from the receptor-docked alignment. The receptor-docked alignment produced statistically superior results compared to either the FlexS alignment or the realignment in both datasets. The [(125)I]IOXY set (Model 1) and [(3)H]diprenorphine set (Model 2) gave q(2) values of 0.592 and 0.620, respectively, using the receptor-docked alignment, and both models produced similar CoMFA contour maps that reflected the stereoelectronic features of the receptor model from which they were derived. Each model gave significantly predictive CoMFA statistics (Model 1 PSET r(2)=0.833; Model 2 PSET r(2)=0.813). Based on the CoMFA contour maps, a binding mode was proposed for amine-containing Salvinorin A analogs that provides a rationale for the observation that the beta-epimers (R-configuration) of protonated amines at the C-2 position have a higher affinity than the corresponding alpha-epimers (S-configuration).
Author List
McGovern DL, Mosier PD, Roth BL, Westkaemper RBAuthor
Philip Mosier PhD Assistant Professor in the School of Pharmacy Administration department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
CarbonDiprenorphine
Diterpenes, Clerodane
Humans
Linear Models
Models, Molecular
Propylamines
Quantitative Structure-Activity Relationship
Receptors, Opioid, kappa
Stereoisomerism