1.
Ahlsén, Göran, et al.
(författare)
Resistance profiles of cyclic and linear inhibitors of HIV-1 protease
2002
Ingår i: Antiviral Chemistry & Chemotherapy. - 0956-3202 .- 2040-2066. ; 13:1, s. 27-37
Tidskriftsartikel (refereegranskat) abstract
Resistance to anti-HIV protease drugs is a major problem in the design of AIDS drugs with long-term efficacy. To identify structural features associated with a certain resistance profile, the inhibitory properties of a series of symmetric and asymmetric cyclic sulfamide, cyclic urea and linear transition-state analogue inhibitors of HIV-1 protease were investigated using wild-type and mutant enzyme. To allow a detailed structure-inhibition analysis, enzyme with single, double, triple and quadruple combinations of G48V, V82A, 184V and L90M substitutions was used. Kinetic analysis of the mutants revealed that catalytic efficiency was 1-30% of that for the wild-type enzyme, a consequence of reduced kcat in all cases and an increased KM for all mutants except for the G48V enzyme. The overall structure-inhibitory profiles of the cyclic compounds were similar, and the inhibition of the V82A, 184V and G48V/L90M mutants were less efficient than of the wild-type enzyme. The greatest increase in Ki was generally observed for the 184V mutant and least for the G48V/L90M mutant, and additional combinations of mutations did not result in improved inhibition profiles for the cyclic compounds. An extended analysis of additional mutants, and including a set of linear compounds, showed that the profile was unique for each compound, and did not reveal any general structural features associated with a certain inhibition profile. The effects of structural modifications in the inhibitors, or of mutations, were not additive and they differed depending on their context. The results demonstrate the difficulties in predicting resistance, even for closely related compounds, and designing compounds with improved resistance profiles.
2.
Alterman, Mathias, et al.
(författare)
P1/P1' modified HIV protease inhibitors as tools in two new sensitive surface plasmon resonance biosensor screening assays
2001
Ingår i: European Journal of Pharmaceutical Sciences. - : Elsevier. - 0928-0987 .- 1879-0720. ; 13:2, s. 203-212
Tidskriftsartikel (refereegranskat) abstract
The commonly used HIV-1 protease assays rely on measurements of the effect of inhibitions on the hydrolysis rate of synthetic peptides. Recently an assay based on surface plasmon resonance (SPR) was introduced. We have taken advantage of the fact that the SPR signal is proportional to the mass of the analyte interacting with the immobilised molecule and developed two new improved efficient competition assay methods. Thus, high molecular weight binders were used as amplifiers of the surface plasmon resonance signal. Linkers were attached by a Heck reaction to the para-positions of the P1/P1′ benzyloxy groups of a linear C2-symmetric C-terminal duplicated inhibitor to enable (a) biotin labelling or (b) direct immobilisation of the inhibitor to the biosensor surface matrix. The interaction properties of a series of 17 structurally diverse inhibitors was assessed and compared to previously reported data. The most sensitive assay was obtained by immobilising the enzyme and amplifying the signal with an antibody, giving a detection range between 0.1 nM and 10 μM. Immobilisation of the inhibitor resulted in a stable and durable surface but a narrower detection range (1–100 nM). The two competition assays are anticipated to be very suitable for fast screening of potential HIV inhibitors.
3.
Bäck, Marcus, et al.
(författare)
Novel potent macrocyclic inhibitors of the hepatitis C virus NS3 protease : use of cyclopentane and cyclopentene P2-motifs
2007
Ingår i: Bioorganic & Medicinal Chemistry. - : Elsevier BV. - 0968-0896 .- 1464-3391. ; 15:22, s. 7184-7202
Tidskriftsartikel (refereegranskat) abstract
Several highly potent novel HCV NS3 protease inhibitors have been developed from two inhibitor series containing either a P2 trisubstituted macrocyclic cyclopentane- or a P2 cyclopentene dicarboxylic acid moiety as surrogates for the widely used N-acyl-(4R)-hydroxyproline in the P2 position. These inhibitors were optimized for anti HCV activities through examination of different ring sizes in the macrocyclic systems and further by exploring the effect of P4 substituent removal on potency. The target molecules were synthesized from readily available starting materials, furnishing the inhibitor compounds in good overall yields. It was found that the 14-membered ring system was the most potent in these two series and that the corresponding 13-, 15-, and 16-membered macrocyclic rings delivered less potent inhibitors. Moreover, the corresponding P1 acylsulfonamides had superior potencies over the corresponding P1 carboxylic acids. It is noteworthy that it has been possible to develop highly potent HCV protease inhibitors that altogether lack the P4 substituent. Thus the most potent inhibitor described in this work, inhibitor 20, displays a Ki value of 0.41 nM and an EC50 value of 9 nM in the subgenomic HCV replicon cell model on genotype 1b. To the best of our knowledge this is the first example described in the literature of a HCV protease inhibitor displaying high potency in the replicon assay and lacking the P4 substituent, a finding which should facilitate the development of orally active small molecule inhibitors against the HCV protease.
4.
Ekegren, Jenny K, et al.
(författare)
A new class of HIV-1 protease inhibitors containing a tertiary alcohol in the transition-state mimicking scaffold
2005
Ingår i: Journal of Medicinal Chemistry. - : American Chemical Society (ACS). - 0022-2623 .- 1520-4804. ; 48:25, s. 8098-8102
Tidskriftsartikel (refereegranskat) abstract
Novel HIV-1 protease inhibitors encompassing a tertiary alcohol as part of the transition-state mimicking unit have been synthesized. Variation of the P1‘−P3‘ residues and alteration of the tertiary alcohol absolute stereochemistry afforded 10 inhibitors. High potencies for the compounds with (S)-configuration at the carbon carrying the tertiary hydroxyl group were achieved with Ki values down to 2.4 nM. X-ray crystallographic data for a representative compound in complex with HIV-1 protease are presented.
5.
Ekegren, Jenny K, et al.
(författare)
Microwave-accelerated synthesis of P1'-extended HIV-1 protease inhibitors encompassing a tertiary alcohol in the transition-state mimicking scaffold
2006
Ingår i: Journal of Medicinal Chemistry. - : American Chemical Society (ACS). - 0022-2623 .- 1520-4804. ; 49:5, s. 1828-1832
Tidskriftsartikel (refereegranskat) abstract
Two series of P1'-extended HIV-1 protease inhibitors comprising a tertiary alcohol in the transition-state mimic exhibiting Ki values ranging from 2.1 to 93 nM have been synthesized. Microwave-accelerated palladium-catalyzed cross-couplings were utilized to rapidly optimize the P1' side chain. High cellular antiviral potencies were encountered when the P1' benzyl group was elongated with a 3- or 4-pyridyl substituent (EC50 = 0.18-0.22 microM). X-ray crystallographic data were obtained for three inhibitors cocrystallized with the enzyme.
6.
Ekegren, Jenny, et al.
(författare)
Variations of the P2 Group in HIV-1 Protease Inhibitors Containing a Tertiary Alcohol in the Transition-State Mimicking Scaffold
2006
Ingår i: Organic and biomolecular chemistry. - : Royal Society of Chemistry (RSC). - 1477-0520 .- 1477-0539. ; 4:16, s. 3040-3043
Tidskriftsartikel (refereegranskat) abstract
The development of synthetic protocol leading to HIV-1 protease inhibitors with a tertiary alcohol based transition-state mimicking unit and different P2 side chains was investigated. (2S)-2-benztloxirane-2-carboxylic acid ((S)-5) was used as a key intermediate in the synthesis of the new HIV-1 protease inhibitors. (S)-5 was coupled with different amines using EDC, NMM, and HOBT, resulting in the corresponding amides at low to moderate yields. The observation supports the hypothesis that intramolecular hydrogen bonding to the tertiary alcohol in the transition-state mimic is present in these molecules. Purification by reverse-phase LC-MS resulted in moderate to good yields of most target compounds. The HIV-1 protease inhibition data suggest that the size and polarity of the P2 substituent are crucial to allow proper accommodation in the S2 sub-site.
7.
8.
Hämäläinen, Markku D., et al.
(författare)
Characterization of a set of HIV-1 protease inhibitors using binding kinetics data from a biosensor-based screen
2000
Ingår i: Journal of Biomolecular Screening. - : Elsevier BV. - 1087-0571 .- 1552-454X. ; 5:5, s. 353-359
Tidskriftsartikel (refereegranskat) abstract
The interaction between 290 structurally diverse human immunodeficiency virus type 1 (HIV-1) protease inhibitors and the immobilized enzyme was analyzed with an optical biosensor, Although only a single concentration of inhibitor was used, information about the kinetics of the interaction could be obtained by extracting binding signals at discrete time points. The statistical correlation between the biosensor binding data, inhibition of enzyme activity (K-i), and viral replication (EC50) revealed that the association and dissociation rates for the interaction could be resolved and that they were characteristic for the compounds. The most potent inhibitors, with respect to K-i and EC50 values, including the clinically used drugs, all exhibited fast association and slow dissociation rates. Selective or partially selective binders for HIV-1 protease could be distinguished from compounds that showed a general protein-binding tendency by using three reference target proteins. This biosensor-based direct binding assay revealed a capacity to efficiently provide high-resolution information on the interaction kinetics and specificity of the interaction of a set of compounds with several targets simultaneously.
9.
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