Stereoisomers of ketoconazole: preparation and biological activity.

Article Details

Citation

Rotstein DM, Kertesz DJ, Walker KA, Swinney DC

Stereoisomers of ketoconazole: preparation and biological activity.

J Med Chem. 1992 Jul 24;35(15):2818-25.

PubMed ID
1495014 [ View in PubMed
]
Abstract

The four stereoisomers of the antifungal agent ketoconazole (1) were prepared and evaluated for their selectivity in inhibiting a number of cytochrome P-450 enzymes. Large differences in selectivity among the isomers were observed for inhibition of the cytochromes P-450 involved in steroid biosynthesis, whereas little differences was observed for inhibition of those associated with hepatic drug metabolism. The cis-(2S,4R) isomer 2 was the most effective against rat lanosterol 14 alpha-demethylase, (2S,4R)-2 greater than (2R,4S)-4 much greater than (2R,4R)-3 = (2S,4S)-5, and progesterone 17 alpha,20-lyase, (2S,4R)-2 much greater than (2S,4S)-5 greater than (2R,4R)-3 = (2R,4S)-4, whereas the cis-(2R,4S) isomer 4 was more effective against cholesterol 7 alpha-hydroxylase, (2R,4S)-4 greater than (2S,4S)-5 greater than (2R,4R)-3, greater than (2S,4R)-2, and the trans-(2S,4S) isomer 5 was the most effective against aromatase, (2S,4R)-5 much greater than (2R,4R)-3 = (2R,4S)-4 greater than (2S,4R)-2. The cis-(2S,4R) and trans-(2R,4R) isomers 2 and 3 are equipotent in inhibiting corticoid 11 beta-hydroxylase and much more effective than their antipodes. Little selectivity was observed for inhibition of cholesterol side chain cleavage or xenobiotic hydroxylase. These data indicate that the affinity of azoles for cytochrome P-450 enzymes involved in steroid synthesis is highly dependent on the stereochemistry of the entire molecule, whereas binding to drug metabolizing enzymes is a less selective process.

DrugBank Data that Cites this Article

Drugs
Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
LevoketoconazoleCholesterol side-chain cleavage enzyme, mitochondrialProteinHumans
Yes
Inhibitor
Details
LevoketoconazoleCytochrome P450 11B1, mitochondrialProteinHumans
Yes
Inhibitor
Details
LevoketoconazoleCytochrome P450 11B2, mitochondrialProteinHumans
Yes
Inhibitor
Details
LevoketoconazoleLanosterol 14-alpha demethylaseProteinHumans
No
Inhibitor
Details
LevoketoconazoleSteroid 17-alpha-hydroxylase/17,20 lyaseProteinHumans
Yes
Inhibitor
Details
Drug Enzymes
DrugEnzymeKindOrganismPharmacological ActionActions
LevoketoconazoleCytochrome P450 19A1ProteinHumans
No
Inhibitor
Details
LevoketoconazoleCytochrome P450 7A1ProteinHumans
No
Inhibitor
Details
LevoketoconazoleSteroid 21-hydroxylaseProteinHumans
No
Inhibitor
Details
Binding Properties
DrugTargetPropertyMeasurementpHTemperature (°C)
KetoconazoleCytochrome P450 3A4IC 50 (nM)1260N/AN/ADetails
KetoconazoleCytochrome P450 3A4IC 50 (nM)897N/AN/ADetails
KetoconazoleCytochrome P450 3A4IC 50 (nM)570N/AN/ADetails