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Stereochemistry ACHIRAL
Molecular Formula C11H11NO2
Molecular Weight 189.211
Optical Activity NONE
Defined Stereocenters 0 / 0
E/Z Centers 0
Charge 0







Molecular Formula C11H11NO2
Molecular Weight 189.211
Charge 0
Stereochemistry ACHIRAL
Additional Stereochemistry No
Defined Stereocenters 0 / 0
E/Z Centers 0
Optical Activity NONE

3-Indolepropionic acid (IN-OX1; Indole-3-propionic acid; OX-1; Oxigon; SHP 22; SHP-622; VP-20629), an endogenous substance produced by bacteria in the intestine, is a deamination product of Tryptophan (T947200) that protects the hippocampus (studied in gerbils) from ischemic damage and oxidative stress. It’s ability to protect the neurons in this way is attributed to its potent antioxidative effects. 3-Indolepropionic acid is also hypothesized to have protective effects on the thyroid gland. 3-Indolepropionic acid is being studied for therapeutic use in Alzheimer's disease. 3-Indolepropionic acid (IPA) completely protected primary neurons and neuroblastoma cells against oxidative damage and death caused by exposure to Abeta, by inhibition of superoxide dismutase, or by treatment with hydrogen peroxide. In kinetic competition experiments using free radical-trapping agents, the capacity of IPA to scavenge hydroxyl radicals exceeded that of melatonin, an indoleamine considered to be the most potent naturally occurring scavenger of free radicals. In contrast with other antioxidants, IPA was not converted to reactive intermediates with pro-oxidant activity. In 2011, Intellect redirected the focus of the OX1 program from Alzheimer's disease to FA (Friedreich's Ataxia). Research suggests that the symptoms associated with FA are the result of oxidative stress caused by the abnormal accumulation of iron. OX1's ability to neutralize ROS could be an effective agent to reduce oxidative stress in FA, thereby eliminating the symptoms of FA and increasing both quality of life and longevity in affected individuals.

Approval Year





Relative efficacies of indole antioxidants in reducing autoxidation and iron-induced lipid peroxidation in hamster testes.
Indole-3-propionic acid, a melatonin-related molecule, protects hepatic microsomal membranes from iron-induced oxidative damage: relevance to cancer reduction.
Carcinogen-induced, free radical-mediated reduction in microsomal membrane fluidity: reversal by indole-3-propionic acid.
2001 Feb
Characterization of the FAD-containing N-methyltryptophan oxidase from Escherichia coli.
2001 Feb 6
The role of water bridges in directing the conformational preferences of 3-indole-propionic acid and tryptamine.
2001 Jun 13
Comparison of the protective effect of melatonin with other antioxidants in the hamster kidney model of estradiol-induced DNA damage.
2001 Mar 1
Development of indole-3-propionic acid (OXIGON) for Alzheimer's disease.
2002 Aug-Oct
Amelioration of hepatic ischemia/reperfusion injury using indolepropionic acid.
2002 Dec
In vitro organogenesis and genetic transformation in popular Cucumis sativus L. through Agrobacterium tumefaciens.
2002 Mar
Degradation of tryptophan and related indolic compounds by ruminal bacteria, protozoa and their mixture in vitro.
Metabolic profiling of root exudates of Arabidopsis thaliana.
2003 Apr 23
Effects of phthalic anhydride modification on horseradish peroxidase stability and activity.
2003 Jan 20
A liquid chromatographic-tandem mass spectrometric method for the analysis of serotonin and related indoles in human whole blood.
2003 Oct
Increased tryptophan decarboxylase and monoamine oxidase activities induce Sekiguchi lesion formation in rice infected with Magnaporthe grisea.
2003 Oct
A novel auxin conjugate hydrolase from wheat with substrate specificity for longer side-chain auxin amide conjugates.
2004 Aug
Endogenous and dietary indoles: a class of antioxidants and radical scavengers in the ABTS assay.
2004 Mar
Determination of phytohormones of environmental impact by capillary zone electrophoresis.
2004 Mar 24
Prediction of genotoxicity of chemical compounds by statistical learning methods.
2005 Jun
Direct measurement of the energy thresholds to conformational isomerization. II. 3-indole-propionic acid and its water-containing complex.
2005 Jun 1
Comparison of potential protective effects of melatonin, indole-3-propionic acid, and propylthiouracil against lipid peroxidation caused by potassium bromate in the thyroid gland.
2005 May 1
Mass spectrometry-based screening for inhibitors of beta-amyloid protein aggregation.
2005 Nov 1
Serotonin, L-tryptophan, and tryptamine are effective inhibitors of the amino acid transport system PAT1.
2005 Sep
Lanthanide(III) and Yttrium(III) Complexes of Benzimidazole-2-Acetic Acid: Synthesis, Characterisation and Effect of La(III) Complex on Germination of Wheat.
Structure-based design of indole propionic acids as novel PPARalpha/gamma co-agonists.
2006 Aug 1
Production of indolic compounds by rumen bacteria isolated from grazing ruminants.
2006 Jun
Laser probes of conformational isomerization in flexible molecules and complexes.
2006 Mar 30
On the energy landscapes of 3-indole acetic acid and 3-indole propionic acid. A study of side chain flexibilities in their S(0) and S(1) electronic states.
2006 Mar 7
Melatonin in Alzheimer's disease and other neurodegenerative disorders.
2006 May 4
Fluorinated amphiphilic amino acid derivatives as antioxidant carriers: a new class of protective agents.
2006 May 4
Protective effects of melatonin and indole-3-propionic acid against lipid peroxidation, caused by potassium bromate in the rat kidney.
2006 Nov-Dec
Multicomponent synthesis of 3-indolepropionic acids.
2007 Jan 18
Analytical method for beta-amyloid fibrils using CE-laser induced fluorescence and its application to screening for inhibitors of beta-amyloid protein aggregation.
2007 Jul 1
Mutation of E1-CONJUGATING ENZYME-RELATED1 decreases RELATED TO UBIQUITIN conjugation and alters auxin response and development.
2007 Jun
Binding behavior of amino acid conjugates of indole-3-acetic acid to immobilized human serum albumin.
2007 Jun 22
The tryptophan aminotransferase Tam1 catalyses the single biosynthetic step for tryptophan-dependent pigment synthesis in Ustilago maydis.
2008 Apr
Identification and quantitation of auxins in plants by liquid chromatography/electrospray ionization ion trap mass spectrometry.
2008 Aug
Syntheses of IAA- and IPA-amino acid conjugates.
2008 Nov 21
Enantioselective Friedel-Crafts alkylation of indoles with alkylidene malonates catalyzed by N,N'-dioxide-scandium(III) complexes: asymmetric synthesis of beta-carbolines.
Evaluation of indole-based probes for high-throughput screening of drug binding to human serum albumin: Analysis by high-performance affinity chromatography.
2009 Apr
[Relationship between toxic effects of potassium bromate and endocrine glands].
2009 Jan-Feb
Indole-3-propionic acid attenuates neuronal damage and oxidative stress in the ischemic hippocampus.
2009 Jul
Structural insight into the inhibition of human kynurenine aminotransferase I/glutamine transaminase K.
2009 May 14
[Metabonomic profiling of plasma metabolites in Wistar rats to study the effect of aging by means of GC/TOFMS-based techniques].
2009 Oct
Auxin amidohydrolases from Brassica rapa cleave the alanine conjugate of indolepropionic acid as a preferable substrate: a biochemical and modeling approach.
2009 Sep
Melatonin restores the basal level of lipid peroxidation in rat tissues exposed to potassium bromate in vitro.
A novel endogenous indole protects rodent mitochondria and extends rotifer lifespan.
2010 Apr 21
Comprehensive feature analysis for sample classification with comprehensive two-dimensional LC.
2010 Jun
Clinical aspects of melatonin intervention in Alzheimer's disease progression.
2010 Sep
Organic cadmium complexes as proteasome inhibitors and apoptosis inducers in human breast cancer cells.
2013 Jun

Sample Use Guides

Friedreich's Ataxia treatment: subjects will receive multiple doses of 3-Indolepropionic acid (VP 20629) (300 mg, 600 mg, or 900 mg total daily dose) or placebo. VP20629 or placebo will be administered every 8 hours for 7 days with a single morning dose on Day 8.
Route of Administration: Oral
In the primary rat hippocampal cultures evaluated by bodipy green fluorescence, 1uM Abeta treatment resulted in almost complete reduction of cell fluorescence as compared with untreated cells. In these experiments, similar concentrations (1 uM) of 3-Indolepropionic acid (IPA) or melatonin added to Abeta-containing media were sufficient to provide full protection from the neurotoxic effects of Abeta, as evidenced by levels of fluorescence comparable to control primary neurons.
Substance Class Chemical
by admin
on Sat Jun 26 12:35:45 UTC 2021
by admin
on Sat Jun 26 12:35:45 UTC 2021
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Created by admin on Sat Jun 26 12:35:45 UTC 2021 , Edited by admin on Sat Jun 26 12:35:45 UTC 2021
Created by admin on Sat Jun 26 12:35:45 UTC 2021 , Edited by admin on Sat Jun 26 12:35:45 UTC 2021
Created by admin on Sat Jun 26 12:35:45 UTC 2021 , Edited by admin on Sat Jun 26 12:35:45 UTC 2021
Created by admin on Sat Jun 26 12:35:45 UTC 2021 , Edited by admin on Sat Jun 26 12:35:45 UTC 2021
Created by admin on Sat Jun 26 12:35:45 UTC 2021 , Edited by admin on Sat Jun 26 12:35:45 UTC 2021
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Created by admin on Sat Jun 26 12:35:45 UTC 2021 , Edited by admin on Sat Jun 26 12:35:45 UTC 2021
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