Dual aromatase-sulfatase inhibitors based on the anastrozole template: synthesis, in vitro SAR, molecular modelling and in vivo activity.
The synthesis and biological evaluation of a series of novel Dual Aromatase-Sulfatase Inhibitors (DASIs) are described. It is postulated that dual inhibition of the aromatase and steroid sulfatase enzymes, both responsible for the biosynthesis of oestrogens, will be beneficial in the treatment of hormone-dependent breast cancer. The compounds are based upon the Anastrozole aromatase inhibitor template which, while maintaining the haem ligating triazole moiety crucial for enzyme inhibition, was modified to include a phenol sulfamate ester motif, the pharmacophore for potent irreversible steroid sulfatase inhibition. Adaption of a synthetic route to Anastrozole was accomplished via selective radical bromination and substitution reactions to furnish a series of inhibitory aromatase pharmacophores. Linking these fragments to the phenol sulfamate ester moiety employed S(N)2, Heck and Mitsunobu reactions with phenolic precursors, from where the completed DASIs were achieved via sulfamoylation. In vitro, the lead compound, 11, had a high degree of potency against aromatase (IC(50) 3.5 nM), comparable with that of Anastrozole (IC(50) 1.5 nM) whereas, only moderate activity against steroid sulfatase was found. However, in vivo, 11 surprisingly exhibited potent dual inhibition. Compound 11 was modelled into the active site of a homology model of human aromatase and the X-ray crystal structure of steroid sulfatase.
Jackson
Toby
T
Medicinal Chemistry, Department of Pharmacy and Pharmacology and Sterix Ltd, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
Woo
L W Lawrence
LW
Trusselle
Melanie N
MN
Chander
Surinder K
SK
Purohit
Atul
A
Reed
Michael J
MJ
Potter
Barry V L
BV
D000077384:Anastrozole; D047072:Aromatase Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009570:Nitriles / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013329:Structure-Activity Relationship; D013429:Sulfatases / Q000037:antagonists & inhibitors*; D014230:Triazoles / Q000737:chemistry*
D047072:Aromatase Inhibitors; D004791:Enzyme Inhibitors; D009570:Nitriles; D014230:Triazoles; D000077384:Anastrozole; D013429:Sulfatases