Compile Data Set for Download or QSAR
maximum 50k data
Found 49 Enz. Inhib. hit(s) for PDB: 1HXW
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.0150nMAssay Description:Inhibition constant of ritonavir towards HIV protease was determinedMore data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.0150nMAssay Description:Tested for inhibitor binding of wild-type HIV PRMore data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.0200nMAssay Description:Inhibitory activity against purified HIV proteaseMore data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599,Q508K,L534I,L564I,C568A,C596A](Human immunodeficiency virus type 1)
Glaxosmithkline

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.0200nM ΔG°:  -61.1kJ/molepH: 6.4 T: 2°CAssay Description:The Ki values were determined using fluorogenic substrate, 2-(aminobenzoyl)-Thr-Ile-Nle-Phe(p-NO2)-Gln-ArgNH2. A standard curve relating changes in f...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [489-587,Q496K](Human immunodeficiency virus type 1)
The Johns Hopkins University

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.0270nM ΔG°:  -60.3kJ/molepH: 5.0 T: 2°CAssay Description:Protease activity was determined by following the increase in fluorescence with hydrolysis of the fluorogenic substrate Arg-Glu(EDANS)-Ser-Gln-Asn-Ty...More data for this Ligand-Target Pair
TargetHIV-1 protease(Human immunodeficiency virus)
University Of Maryland

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.0600nMAssay Description:Inhibition assay using HIV protease and Sulfonamide compounds.More data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.0620nMAssay Description:Dissociation constant obtained by inhibition of Wild-type proteaseMore data for this Ligand-Target Pair
TargetProtease(Human immunodeficiency virus 1 (HIV-1))
Dainippon Sumitomo Pharma

Curated by ChEMBL
LigandPNGBDBM50088504(A-84538 | ABBOTT-84538 | CHEBI:45409 | Norvir | Ri...)
Affinity DataKi:  0.0980nMAssay Description:Inhibition of HIV1 proteaseMore data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.120nMAssay Description:Tested for inhibitor binding of D25N/V82A mutant of HIV PRMore data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599,M537I](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.150nM ΔG°:  -58.3kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constant, Ki was determined by monitoring the competitive inhibition of the hydrolysis of the chromogenic substrate.More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [482-580,I502K,I528M,T553A](Human immunodeficiency virus type 1)
Johnson & Johnson Pharmaceutical

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.200nM ΔG°:  -57.6kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599,Q508K,L534I,L564I,C568A,C596A,D531N](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.230nM ΔG°:  -57.2kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constant, Ki was determined by monitoring the competitive inhibition of the hydrolysis of the chromogenic substrate.More data for this Ligand-Target Pair
TargetHIV-1 protease(Human immunodeficiency virus)
Dupont Pharmaceuticals

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.370nMpH: 5.5Assay Description:Protease inhibition fluorescence-based assay using cyclic ureas to inhibit HIV-protease.More data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.370nMAssay Description:Inhibitory activity against HIV-1 proteaseMore data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.370nMAssay Description:Binding affinity to inhibit the purified wild-type HIV-1 ProteaseMore data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.370nMAssay Description:Affinity of the compound against HIV proteaseMore data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.370nMAssay Description:Binding affinity for HIV -1 ProteaseMore data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [491-589,Q498K,D521N,V555I,N579D](Human immunodeficiency virus type 1)
University Of Massachusetts Medical School

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.460nMAssay Description:HIV-1 protease inhibitor activities were determined by the fluorescence resonance energy transfer (FRET) method. The energy transfer donor (EDANS) an...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599,A572V](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.5nM ΔG°:  -55.2kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constant, Ki was determined by monitoring the competitive inhibition of the hydrolysis of the chromogenic substrate.More data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.590nM Kd:  0.608nM Koff:  3.92E+6s-1Assay Description:Association rate constant for the interaction between inhibitor and HIV-1 proteaseMore data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.590nMAssay Description:Inhibition constant for human immunodeficiency virus type 1 proteaseMore data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599](Human immunodeficiency virus type 1)
Johnson & Johnson Pharmaceutical

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.700nM ΔG°:  -54.4kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.700nM ΔG°:  -54.4kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constant, Ki was determined by monitoring the competitive inhibition of the hydrolysis of the chromogenic substrate.More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.700nM ΔG°:  -54.4kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetProtease(Human immunodeficiency virus 1 (HIV-1))
Dainippon Sumitomo Pharma

Curated by ChEMBL
LigandPNGBDBM50088504(A-84538 | ABBOTT-84538 | CHEBI:45409 | Norvir | Ri...)
Affinity DataKi:  0.800nMAssay Description:Inhibition of HIV1 protease expressed in Escherichia coli by fluorometric assayMore data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [489-587,Q496K,I573V](Human immunodeficiency virus type 1)
The Johns Hopkins University

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  0.910nM ΔG°:  -51.6kJ/molepH: 5.0 T: 2°CAssay Description:Protease activity was determined by following the increase in fluorescence with hydrolysis of the fluorogenic substrate Arg-Glu(EDANS)-Ser-Gln-Asn-Ty...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599,M537I,A572V](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  1.10nM ΔG°:  -53.2kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constant, Ki was determined by monitoring the competitive inhibition of the hydrolysis of the chromogenic substrate.More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [490-588,L523I,E525D,M526I,I544V,L553H,H559K,L579M](Human immunodeficiency virus type 1)
Johnson & Johnson Pharmaceutical

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  1.20nMAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599,D531N,A572V](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  2.40nM ΔG°:  -51.2kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constant, Ki was determined by monitoring the competitive inhibition of the hydrolysis of the chromogenic substrate.More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [491-589,Q498K,L501I,V555I,A562V,G564S,I575V,L581M](Human immunodeficiency virus type 1)
University Of Massachusetts Medical School

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  2.81nMAssay Description:HIV-1 protease inhibitor activities were determined by the fluorescence resonance energy transfer (FRET) method. The energy transfer donor (EDANS) an...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [491-589,Q498K,L501I,G539V,I545V,V555I,V573A](Human immunodeficiency virus type 1)
University Of Massachusetts Medical School

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  3.02nMAssay Description:HIV-1 protease inhibitor activities were determined by the fluorescence resonance energy transfer (FRET) method. The energy transfer donor (EDANS) an...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [482-580,I502K,I528M,T553A,V564F](Human immunodeficiency virus type 1)
Johnson & Johnson Pharmaceutical

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  3.10nMAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599,V583F](Human immunodeficiency virus type 1)
Johnson & Johnson Pharmaceutical

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  4nM ΔG°:  -49.9kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599,D531N,M537I](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  4.5nM ΔG°:  -49.6kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constant, Ki was determined by monitoring the competitive inhibition of the hydrolysis of the chromogenic substrate.More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [501-599,D531N,M537I,A572V](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  13nM ΔG°:  -46.8kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constant, Ki was determined by monitoring the competitive inhibition of the hydrolysis of the chromogenic substrate.More data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  23nMAssay Description:Dissociation constant obtained by inhibition of mutant HIV-protease (V-18)More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [489-587,K509R,V521I,L522F,M525I,L552P,A560V,V571A,L579M](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  30nM ΔG°:  -44.7kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [490-588,L523I,E525D,M526I,I544V,L553H,H559K,V572F,L579M](Human immunodeficiency virus type 1)
Johnson & Johnson Pharmaceutical

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  32nMAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  40nMAssay Description:Dissociation constant obtained by inhibition of mutant HIV-protease (K-60)More data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  60nMAssay Description:Dissociation constant obtained by inhibition of mutant HIV-protease (A-44)More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [489-587,K509R,V521I,L522F,M525I,I543V,L552P,A560V,V571A,L579M](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  109nM ΔG°:  -41.3kJ/molepH: 4.7 T: 2°CAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [489-587,K509R,V521I,L522F,M525I,L552P,A560V,V571A,I573V,L579M](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  165nMAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [489-587,K509R,V521I,L522F,M525I,M535I,I543V,L552P,A560V,V571A,I573V,L579M](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  624nMAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [489-587,K509R,V521I,L522F,M525I,I543V,L552P,A560V,V571A,I573V,L579M](Human immunodeficiency virus type 1)
University Of Florida College Of Medicine

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKi:  932nMAssay Description:The inhibition constants Ki were determined by monitoring the inhibition of hydrolysis of the chromogenic substrate using a Hewlett-Packard 8452A spe...More data for this Ligand-Target Pair
TargetDimer of Gag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
Abbott Laboratories

LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataIC50:  67nMpH: 4.5 T: 2°CAssay Description:HIV-1 protease inhibition was measured by a fluorescence assay using recombinant HIV-1 protease. The reactions were initiated by the addition of 1 nM...More data for this Ligand-Target Pair
TargetProtease(Human immunodeficiency virus 1 (HIV-1))
Dainippon Sumitomo Pharma

Curated by ChEMBL
LigandPNGBDBM50088504(A-84538 | ABBOTT-84538 | CHEBI:45409 | Norvir | Ri...)
Affinity DataIC50:  9.85E+3nMAssay Description:Inhibition of HIV1 proteaseMore data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKon:  0.00216M-1s-1Assay Description:Association rate constant for the interaction between inhibitor and HIV-1 proteaseMore data for this Ligand-Target Pair
TargetGag-Pol polyprotein [489-587](Human immunodeficiency virus type 1)
TBA

Curated by ChEMBL
LigandPNGBDBM520(1,3-thiazol-5-ylmethyl N-[(2S,3S,5S)-3-hydroxy-5-[...)
Affinity DataKd:  0.600nMAssay Description:Binding affinity for human immunodeficiency virus type 1 proteaseMore data for this Ligand-Target Pair
TargetProtease(Human immunodeficiency virus 1 (HIV-1))
Dainippon Sumitomo Pharma

Curated by ChEMBL
LigandPNGBDBM50088504(A-84538 | ABBOTT-84538 | CHEBI:45409 | Norvir | Ri...)
Affinity DataEC50:  150nMAssay Description:Inhibition of HIV1 3B protease infected in human MT4 cells assessed as protection from virus induced cytopathogenicity measured after 5 days post inf...More data for this Ligand-Target Pair