Planarity and constraint of the carbonyl groups in 1,2-diones are determinants for selective inhibition of human carboxylesterase 1.
Carboxylesterases (CE) are ubiquitous enzymes responsible for the detoxification of xenobiotics, including numerous clinically used drugs. Therefore, the selective inhibition of these proteins may prove useful in modulating drug half-life and bioavailability. Recently, we identified 1,2-diones as potent inhibitors of CEs, although little selectivity was observed in the inhibition of either human liver CE (hCE1) or human intestinal CE (hiCE). In this paper, we have further examined the inhibitory properties of ethane-1,2-diones toward these proteins and determined that, when the carbonyl oxygen atoms are cis-coplanar, the compounds demonstrate specificity for hCE1. Conversely, when the dione oxygen atoms are not planar (or are trans-coplanar), the compounds are more potent at hiCE inhibition. These properties have been validated in over 40 1,2-diones that demonstrate inhibitory activity toward at least one of these enzymes. Statistical analysis of the results confirms the correlation (P < 0.001) between the dione dihedral angle and the preferential inhibition of either hiCE or hCE1. Overall, the results presented here define the parameters necessary for small molecule inhibition of human CEs.
Hyatt
Janice L
JL
Department of Molecular Pharmacology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105-2794, USA. phil.potter@stjude.org
Wadkins
Randy M
RM
Tsurkan
Lyudmila
L
Hicks
Latorya D
LD
Hatfield
M Jason
MJ
Edwards
Carol C
CC
Ross
Charles R
CR
Cantalupo
Stephanie A
SA
Crundwell
Guy
G
Danks
Mary K
MK
Guy
R Kip
RK
Potter
Philip M
PM
D000110:Acetylcholinesterase / Q000737:chemistry; D002091:Butyrylcholinesterase / Q000737:chemistry; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors* / Q000737:chemistry; D018360:Crystallography, X-Ray; D006037:Glyoxal / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D006801:Humans; D007422:Intestines / Q000201:enzymology; D008958:Models, Molecular; D015394:Molecular Structure; D021281:Quantitative Structure-Activity Relationship
D006037:Glyoxal; D002265:Carboxylic Ester Hydrolases; C474609:CES1 protein, human; D000110:Acetylcholinesterase; D002091:Butyrylcholinesterase