title: Discovery of Nanomolar Dengue and West Nile Virus Protease Inhibitors Containing a 4-Benzyloxyphenylglycine Residue.
abstract: The dengue virus (DENV) and West Nile Virus (WNV) NS2B-NS3 proteases are attractive targets for the development of dual-acting therapeutics against these arboviral pathogens. We present the synthesis and extensive biological evaluation of inhibitors that contain benzyl ethers of 4-hydroxyphenylglycine as non-natural peptidic building blocks synthesized via a copper-complex intermediate. A three-step optimization strategy, beginning with fragment growth of the C-terminal 4-hydroxyphenylglycine to the benzyloxy ether, followed by C- and N-terminal optimization, and finally fragment merging generated compounds with in vitro affinities in the low nanomolar range. The most promising derivative reached Ki values of 12 nM at the DENV-2 and 39 nM at the WNV proteases. Several of the newly discovered protease inhibitors yielded a significant reduction of dengue and West Nile virus titers in cell-based assays of virus replication, with an EC50 value of 3.4 μM at DENV-2 and 15.5 μM at WNV for the most active analogue.
authors.affiliation: Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University , Im Neuenheimer Feld 364, 69120 Heidelberg, Germany.
authors.forename: Mira A M
authors.initials: MA
authors.lastname: Behnam
authors.affiliation: Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University , Im Neuenheimer Feld 364, 69120 Heidelberg, Germany.
authors.forename: Dominik
authors.initials: D
authors.lastname: Graf
authors.affiliation: Department of Infectious Diseases, Molecular Virology, Heidelberg University , Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.|German Center for Infection Research, Heidelberg University , Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Bartenschlager
authors.affiliation: Department of Pharmaceutical Chemistry, The German University in Cairo , New Cairo City, 11835 Cairo, Egypt.
authors.forename: Darius P
authors.initials: DP
authors.lastname: Zlotos
authors.affiliation: Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University , Im Neuenheimer Feld 364, 69120 Heidelberg, Germany.
authors.forename: Christian D
authors.initials: CD
authors.lastname: Klein
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D001565:Benzoates / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D002460:Cell Line; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D062105:Molecular Docking Simulation; D010447:Peptide Hydrolases / Q000378:metabolism; D010455:Peptides / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D011480:Protease Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D017207:Rats, Sprague-Dawley; D014901:West Nile Fever / Q000188:drug therapy / Q000821:virology; D014902:West Nile virus / Q000187:drug effects* / Q000201:enzymology*
chemical_list: D000998:Antiviral Agents; D001565:Benzoates; D010455:Peptides; D011480:Protease Inhibitors; C023010:4-hydroxyphenylglycine; D010447:Peptide Hydrolases; D005998:Glycine