Indoleamine 2, 3-dioxygenase (IDO) is an intracellular enzyme that catalyzes the transformation of L-tryptophan to N-formylkynurenine, which is the first and rate-controlling step in the kynurenine pathway. IDO is a rate-limiting enzyme that catalyzes the degradation of tryptophan into kynurenine and is recognized to exert a tolerizing effect on T cells that require tryptophan to proliferate5. IDO also plays an important role in the activation and regulation of functionally quiescent regulatory T cells. IDO is a heme-containing enzyme that catalyzes the oxidative cleavage of 2,3 double bond of indole ring. IDO has the ability to inhibit T-cell activation by tryptophan starvation, whereas T-cell survival and proliferation are regulated by O2 free radicals and kynurenine derivatives. IDO plays a crucial role in autoimmunity,infections and malignancies. Indoleamine-2,3-dioxygenase (IDO) one of the most important immunoregulator enzyme responsible for metabolism of tryptophan as part of Kynurenin pathway. Tryptophan is catabolized in the tumor tissue by the rate-limiting enzyme IDO expressed in tumor cells or antigen presenting cells.


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BMT-297376

BMT-297376, the optimized Linrodostat, is a potent IDO1 inhibitor[1].

  • CAS Number: 2251031-81-7
  • MF: C23H29F2N3O3
  • MW: 433.49
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

IACS-8968 S-enantiomer

IACS-8968 (S-enantiomer) is the S-enantiomer of IACS-8968. IACS-8968 is a dual IDO and TDO inhibitor, with pIC50s of 6.43 for IDO and <5 for TDO, respectively.

  • CAS Number: 2239305-70-3
  • MF: C17H18F3N5O2
  • MW: 381.35
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

IDO antagonist-1

IDO antagonist-1 (compound 163) is an antagonist of IDO . IDO antagonist-1 inhibits pancreatic adenocarcinoma cells growth in C57BL/6 mice[1].

  • CAS Number: 2206797-88-6
  • MF: C39H53N7O5
  • MW: 699.88
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

IDO-IN-4

IDO-IN-4 is an indoleamine 2,3-dioxygenase 1 (IDO-1) inhibitor, extracted from patent WO2014150677A1, Compound example 1 enantiomer 1.

  • CAS Number: 1629125-65-0
  • MF: C26H35N3O3
  • MW: 437.574
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: 1.2±0.1 g/cm3
  • Boiling Point: 532.6±50.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 275.9±30.1 °C

DP00477

DP00477 is a potent IDO1 (indoleamine 2,3-dioxygenase 1) inhibitor with an IC50 value of 7.0 µM. DP00477 has the potential for the research of cancer[1].

  • CAS Number: 169120-56-3
  • MF: C17H11ClF3N3OS
  • MW: 397.80
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

LY-3381916

LY-3381916 is a potent, selective and brain penetrated inhibitor of IDO1 activity, binds to apo-IDO1 lacking heme rather than mature heme-bound IDO1[1].

  • CAS Number: 2166616-75-5
  • MF: C23H25FN2O3
  • MW: 396.45
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

(S)-Indoximod-d3

(S)-Indoximod-d3 is the deuterium labeled (S)-Indoximod. (S)-Indoximod (1-Methyl-L-tryptophan) is an inhibitor of indoleamine 2,3-dioxygenase (IDO). (S)-Indoximod can be used for the research of cancer[1][2][3].

  • CAS Number: 1801851-87-5
  • MF: C12H11D3N2O2
  • MW: 221.27
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

ZC0101

ZC0101 is a potent, orally active IDO1 and TrxR dual inhibitor with IC50 values of 0.084 μM and 7.98 μM, respectively. ZC0101 effectively induces apoptosis and ROS accumulation in cancer cells[1].

  • CAS Number: 2541604-52-6
  • MF: C17H15N3O2
  • MW: 293.32
  • Catalog: Apoptosis
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

BMS-986242

BMS-986242 is an orally active, potent and selective indoleamine-2,3-dioxygenase 1 (IDO1) inhibitor. BMS-986242 can be used for the research of cancer[1].

  • CAS Number: 1923844-48-7
  • MF: C24H24ClFN2O
  • MW: 410.91
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

IDO-IN-16

IDO-IN-16 (compound 5) is an IDO inhibitor, with an IC50 of 36 nM[1].

  • CAS Number: 2663591-36-2
  • MF: C22H21F3N4O
  • MW: 414.42
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

IDO/TDO-IN-1

IDO/TDO-IN-1 (compound 25) is a highly potent and orally active dual indoleamine-2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) inhibitor with IC50s of 9.7 and 47 nM, respectively [1].

  • CAS Number: 2033173-01-0
  • MF: C25H24FN5
  • MW: 413.49
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

NUCC-0223619

NUCC-0223619 is an IDO1 inhibitor, induce degradation of IDO protein. NUCC-0223619 can be used to synthesis PROTAC[1].

  • CAS Number: 1923835-78-2
  • MF: C24H24ClFN2O2
  • MW: 426.91
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

IDO-IN-18

IDO-IN-18 (Compound 00815) is an IDO inhibitor. IDO-IN-18 can be used for research of immunosuppression associated infectious or cancer diseases[1].

  • CAS Number: 314027-92-4
  • MF: C10H8N2O2S
  • MW: 220.25
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: 1.5±0.1 g/cm3
  • Boiling Point: 526.6±30.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 272.3±24.6 °C

Coptisine sulfate

Coptisine Sulfate is an alkaloid from Chinese goldthread, and acts as an efficient uncompetitive IDO inhibitor with a Ki value of 5.8 μM and an IC50 value of 6.3 μM[1].

  • CAS Number: 1198398-71-8
  • MF: C19H15NO8S
  • MW: 417.389
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

IDO-IN-5

IDO-IN-5 (NLG-1489) is an indoleamine 2,3-dioxygenase (IDO) inhibitor extracted from patent WO WO2012142237A1, compound 1489, has an IC50 of 1-10 μM.

  • CAS Number: 1402837-79-9
  • MF: C18H21FN2O2
  • MW: 316.370
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: 1.4±0.1 g/cm3
  • Boiling Point: 555.4±35.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 289.7±25.9 °C

IDO1-IN-18

IDO1-IN-18 (Compound 14) is a potent inhibitor of IDO1. IDO1-IN-18 has the potential for the research of cancer diseases[1].

  • CAS Number: 2328099-08-5
  • MF: C23H18F4N2O3
  • MW: 446.39
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

NAMPT/IDO1-IN-1

NAMPT/IDO1-IN-1 is an orally active dual inhibitor of NAMPT and IDO1 with IC50s of 57.7 nM and 233 nM, respectively. NAMPT/IDO1-IN-1 blocks NAD+ biosynthesis, inhibits proliferation and migration of Paclitaxel (HY-B0015)- and FK866 (HY-50876)-resistant NSCLC cell lines (A549/R cells). NAMPT/IDO1-IN-1 has shown antitumor effects in mice and enhanced A549/R cell sensitivity to paclitaxel[1].

  • CAS Number: 2247884-06-4
  • MF: C23H24BrFN8O3
  • MW: 559.39
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

CAY10581

CAY10581, a pyranonaphthoquinone derivative, is a highly specific and reversible uncompetitive IDO Inhibitor with an IC50 of 55 nM[1][2].

  • CAS Number: 1018340-07-2
  • MF: C22H21NO4
  • MW: 363.406
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 548.8±50.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 285.7±30.1 °C

(R)-IDO/TDO-IN-1

(R)-IDO/TDO-IN-1 (compound 25) is an indoleamine-2,3-dioxygenase (IDO) inhibitor, with good pharmacokinetic properties. (R)-IDO/TDO-IN-1 exhibits anti-tumor activity in MC38 xenograft model. (R)-IDO/TDO-IN-1 shows synergistic effect with anti-PD-1 monoclonal antibody (SHR-1210)[1].

  • CAS Number: 2033173-00-9
  • MF: C25H24FN5
  • MW: 413.49
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

NLG919

IDO-IN-7 (NLG-919 analogue) is a a potent IDO1 inhibitor with an IC50 of 38 nM.

  • CAS Number: 1402836-58-1
  • MF: C18H22N2O
  • MW: 282.380
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 524.6±33.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 271.1±25.4 °C

IDO1/2-IN-1

IDO1/2-IN-1 (compound 4t) is the first potent IDO1/IDO2 dual inhibitor with IC50s of 28 nM and 144 nM for IDO1 and IDO2, respectively. IDO1/2-IN-1 exhibits antitumor activies. Orally active[1].

  • CAS Number: 2310286-45-2
  • MF: C16H18BrFN8O4
  • MW: 485.27
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Linrodostat (BMS-986205)

BMS-986205 is a selective indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor.

  • CAS Number: 1923833-60-6
  • MF: C24H24ClFN2O
  • MW: 410.15
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

1-Isopropyltryptophan

1-Isopropyltryptophan (1-IsoPT) is a IDO1 inhibitor. 1-Isopropyltryptophan decreases the expression of IFN-γ stimulated ID0-1 and ID0-2 mRNA[1].

  • CAS Number: 1219485-46-7
  • MF: C14H18N2O2
  • MW: 246.30
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

IDO-IN-3

IDO-IN-3 is a potent indoleamine 2,3-dioxygenase (IDO) inhibitor with an IC50 of 290 nM.

  • CAS Number: 2070018-30-1
  • MF: C11H12BrFN6O2
  • MW: 359.15
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

(Rac)-Indoximod

(Rac)-Indoximod (1-Methyl-DL-tryptophan) is an indoleamine 2,3-dioxygenase (IDO) inhibitor. Co-treatment with IFN-γ and (Rac)-Indoximod markedly reduces the activity of human cardiac myofibroblasts (hCMs) expressing α-SMA and induces apoptosis through up-regulating the IRF-1, Fas, and FasL genes[1].

  • CAS Number: 26988-72-7
  • MF: C12H14N2O2
  • MW: 218.25200
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: 1.28g/cm3
  • Boiling Point: 429.3ºC at 760mmHg
  • Melting Point: 250ºC (dec.)(lit.)
  • Flash Point: 213.4ºC

Coptisine chloride

Coptisine chloride is an alkaloid from Chinese goldthread, and acts as an efficient uncompetitive IDO inhibitor with a Ki value of 5.8 μM and an IC50 value of 6.3 μM.

  • CAS Number: 6020-18-4
  • MF: C19H14ClNO4
  • MW: 355.772
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: 1.51g/cm3
  • Boiling Point: 601.5ºC at 760 mmHg
  • Melting Point: >258ºC (dec.)
  • Flash Point: 190.4ºC

IDO1-IN-19

IDO1-IN-19 (Compound 17) is a potent inhibitor of IDO1. IDO1-IN-19 has the potential for the research of cancer diseases[1].

  • CAS Number: 2328099-11-0
  • MF: C25H22F4N2O3
  • MW: 474.45
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

1H-Naphtho(2,3-d)-1,2,3-triazole-4,9-dione, 1-phenyl-

IDO1/TDO-IN-2 (Compound 1) is a potent inhibitor of IDO1/TDO with IC50s of 0.1 and 0.07 μM. IDO1/TDO-IN-2 has the potential for the research of cancer diseases[1].

  • CAS Number: 5466-47-7
  • MF: C16H9N3O2
  • MW: 275.26
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: 1.44g/cm3
  • Boiling Point: 523.4ºC at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 270.3ºC

IDO-IN-15

IDO-IN-15 is an IDO1 inhibitor (IC50 < 0.51 nM).

  • CAS Number: 2433886-87-2
  • MF: C29H39N5O4
  • MW: 521.65
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

IDO-IN-14

IDO-IN-14 is an IDO inhibitor with an IC50 value of 0.6928 nM.

  • CAS Number: 2568302-02-1
  • MF: C23H23ClN4O2
  • MW: 422.91
  • Catalog: Indoleamine 2,3-Dioxygenase (IDO)
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A