title: Novel protease inhibitors (PIs) containing macrocyclic components and 3(R),3a(S),6a(R)-bis-tetrahydrofuranylurethane that are potent against multi-PI-resistant HIV-1 variants in vitro.
abstract: Natural products with macrocyclic structural features often display intriguing biological properties. Molecular design incorporating macrocycles may lead to molecules with unique protein-ligand interactions. We generated novel human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs) containing a macrocycle and bis-tetrahydrofuranylurethane. Four such compounds exerted potent activity against HIV-1LAI and had 50% effective concentrations (EC50s) of as low as 0.002 microM with minimal cytotoxicity. GRL-216 and GRL-286 blocked the replication of HIV-1NL4-3 variants selected by up to 5 microM saquinavir, ritonavir, nelfinavir, lopinavir, or atazanavir; they had EC50s of 0.020 to 0.046 microM and potent activities against six multi-PI-resistant clinical HIV-1 (HIVmPIr) variants with EC50s of 0.027 to 0.089 microM. GRL-216 and -286 also blocked HIV-1 protease dimerization as efficiently as darunavir. When HIV-1NL4-3 was selected by GRL-216, it replicated progressively more poorly and failed to replicate in the presence of >0.26 microM GRL-216, suggesting that the emergence of GRL-216-resistant HIV-1 variants is substantially delayed. At passage 50 with GRL-216 (the HIV isolate selected with GRL-216 at up to 0.16 microM [HIV216-0.16 microM]), HIV-1NL4-3 containing the L10I, L24I, M46L, V82I, and I84V mutations remained relatively sensitive to PIs, including darunavir, with the EC50s being 3- to 8-fold-greater than the EC50 of each drug for HIV-1NL4-3. Interestingly, HIV216-0.16 microM had 10-fold increased sensitivity to tipranavir. Analysis of the protein-ligand X-ray structures of GRL-216 revealed that the macrocycle occupied a greater volume of the binding cavity of protease and formed greater van der Waals interactions with V82 and I84 than darunavir. The present data warrant the further development of GRL-216 as a potential antiviral agent for treating individuals harboring wild-type and/or HIVmPIr.
authors.affiliation: Department of Hematology, Kumamoto University School of Medicine, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tojo
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Koh
authors.forename: Masayuki
authors.initials: M
authors.lastname: Amano
authors.forename: Manabu
authors.initials: M
authors.lastname: Aoki
authors.forename: Debananda
authors.initials: D
authors.lastname: Das
authors.forename: Sarang
authors.initials: S
authors.lastname: Kulkarni
authors.forename: David D
authors.initials: DD
authors.lastname: Anderson
authors.forename: Arun K
authors.initials: AK
authors.lastname: Ghosh
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Mitsuya
mesh_terms: D002460:Cell Line; D019281:Dimerization; D024921:Drug Resistance, Multiple, Viral / Q000235:genetics*; D005663:Furans / Q000737:chemistry* / Q000494:pharmacology*; D014644:Genetic Variation; D016333:HIV Protease / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D017320:HIV Protease Inhibitors / Q000737:chemistry / Q000494:pharmacology; D015497:HIV-1 / Q000145:classification / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics; D006801:Humans; D047028:Macrocyclic Compounds / Q000737:chemistry / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D013329:Structure-Activity Relationship; D014779:Virus Replication / Q000187:drug effects
chemical_list: D005663:Furans; C553641:GRL-216; C553642:GRL-286; D017320:HIV Protease Inhibitors; D047028:Macrocyclic Compounds; D016333:HIV Protease; C514803:p16 protease, Human immunodeficiency virus 1