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Record Information
Version2.0
Creation Date2009-12-17 01:41:03 UTC
Update Date2018-03-21 17:46:25 UTC
Accession NumberT3D3660
Identification
Common NameGlycolic acid
ClassSmall Molecule
DescriptionGlycolic acid (or hydroxyacetic acid) is the smallest alpha-hydroxy acid (AHA). This colourless, odourless, and hygroscopic crystalline solid is highly soluble in water. Due to its excellent capability to penetrate skin, glycolic acid is often used in skin care products, most often as a chemical peel. It may reduce wrinkles, acne scarring, and hyperpigmentation and improve many other skin conditions, including actinic keratosis, hyperkeratosis, and seborrheic keratosis. Once applied, glycolic acid reacts with the upper layer of the epidermis, weakening the binding properties of the lipids that hold the dead skin cells together. This allows the outer skin to dissolve, revealing the underlying skin. It is thought that this is due to the reduction of calcium ion concentrations in the epidermis and the removal of calcium ions from cell adhesions, leading to desquamation. Glycolic acid is a known inhibitor of tyrosinase. This can suppress melanin formation and lead to a lightening of skin colour. Acute doses of glycolic acid on skin or eyes leads to local effects that are typical of a strong acid (e.g. dermal and eye irritation). Glycolate is a nephrotoxin if consumed orally. A nephrotoxin is a compound that causes damage to the kidney and kidney tissues. Glycolic acid's renal toxicity is due to its metabolism to oxalic acid. Glycolic and oxalic acid, along with excess lactic acid, are responsible for the anion gap metabolic acidosis. Oxalic acid readily precipitates with calcium to form insoluble calcium oxalate crystals. Renal tissue injury is caused by widespread deposition of oxalate crystals and the toxic effects of glycolic acid. Glycolic acid does exhibit some inhalation toxicity and can cause respiratory, thymus, and liver damage if present in very high levels over long periods of time.
Compound Type
  • Cosmetic Toxin
  • Food Toxin
  • Household Toxin
  • Industrial/Workplace Toxin
  • Keratolytic Agent
  • Metabolite
  • Organic Compound
  • Synthetic Compound
Chemical Structure
Thumb
Synonyms
Synonym
2-Hydroxyacetate
2-Hydroxyacetic acid
a-Hydroxyacetate
a-Hydroxyacetic acid
alpha-Hydroxyacetate
alpha-Hydroxyacetic acid
Glycocide
Glycolate
Glycollate
Glycollic acid
GlyPure
GlyPure 70
Hydroxyacetate
Hydroxyacetic acid
Hydroxyethanoate
Hydroxyethanoic acid
Sodium glycolate
Chemical FormulaC2H4O3
Average Molecular Mass76.051 g/mol
Monoisotopic Mass76.016 g/mol
CAS Registry Number79-14-1
IUPAC Name2-hydroxyacetic acid
Traditional Nameglycolic acid
SMILESOCC(O)=O
InChI IdentifierInChI=1S/C2H4O3/c3-1-2(4)5/h3H,1H2,(H,4,5)
InChI KeyInChIKey=AEMRFAOFKBGASW-UHFFFAOYSA-N
Chemical Taxonomy
Description belongs to the class of organic compounds known as alpha hydroxy acids and derivatives. These are organic compounds containing a carboxylic acid substituted with a hydroxyl group on the adjacent carbon.
KingdomOrganic compounds
Super ClassOrganic acids and derivatives
ClassHydroxy acids and derivatives
Sub ClassAlpha hydroxy acids and derivatives
Direct ParentAlpha hydroxy acids and derivatives
Alternative Parents
Substituents
  • Alpha-hydroxy acid
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Carboxylic acid derivative
  • Organic oxygen compound
  • Organic oxide
  • Hydrocarbon derivative
  • Primary alcohol
  • Organooxygen compound
  • Carbonyl group
  • Alcohol
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors
Biological Properties
StatusDetected and Not Quantified
OriginEndogenous
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Mitochondria
  • Peroxisome
Biofluid LocationsNot Available
Tissue Locations
  • Bladder
  • Fibroblasts
  • Liver
  • Skin
  • Stratum Corneum
Pathways
NameSMPDB LinkKEGG Link
Primary Hyperoxaluria Type ISMP00352 Not Available
Applications
Biological Roles
Chemical RolesNot Available
Physical Properties
StateSolid
AppearanceWhite powder.
Experimental Properties
PropertyValue
Melting Point75-80°C
Boiling PointNot Available
Solubility1000 mg/mL at 25°C
LogP-1.11
Predicted Properties
PropertyValueSource
Water Solubility608 g/LALOGPS
logP-1ALOGPS
logP-1ChemAxon
logS0.9ALOGPS
pKa (Strongest Acidic)3.53ChemAxon
pKa (Strongest Basic)-3.6ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area57.53 ŲChemAxon
Rotatable Bond Count1ChemAxon
Refractivity14.35 m³·mol⁻¹ChemAxon
Polarizability6.2 ųChemAxon
Number of Rings0ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash KeyView
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (Non-derivatized)splash10-0002-0900000000-ed8b8e4a9e2556ea02e2JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (2 TMS)splash10-00dj-9600000000-8bafc88c7bf4e90fb5e8JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-MS (2 TMS)splash10-003r-2910000000-bd50bf5bab6f5327eaf4JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-001i-9000000000-cadf899be6b15d008330JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-001i-9000000000-e66ed28d8419895e0fb4JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-0002-0900000000-7f84fac3284d17fa3ba6JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0002-0900000000-ed8b8e4a9e2556ea02e2JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-00dj-9600000000-8bafc88c7bf4e90fb5e8JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-MS (Non-derivatized)splash10-003r-2910000000-bd50bf5bab6f5327eaf4JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0002-0900000000-d724c85a3b30e3c2e4bcJSpectraViewer | MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0a7l-9000000000-1e9466549305eb20257bJSpectraViewer
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (2 TMS) - 70eV, Positivesplash10-05i9-9520000000-5f0019fe63eb6e692109JSpectraViewer
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Negative (Annotated)splash10-004i-9000000000-e942bdae1d60e5f5d649JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Negative (Annotated)splash10-00di-9000000000-f225de2de3540c3f50a4JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Negative (Annotated)splash10-00di-9000000000-7de217d97b44f53aad82JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 10V, Negativesplash10-00di-9000000000-88af2b259f82cd1d8938JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 20V, Negativesplash10-004i-9000000000-c968a24f0640b154325bJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 30V, Negativesplash10-0059-9000000000-1dfacf30bf94ce3bf8bbJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-00di-9000000000-88af2b259f82cd1d8938JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-004i-9000000000-c968a24f0640b154325bJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-0059-9000000000-1dfacf30bf94ce3bf8bbJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 1V, positivesplash10-004i-9000000000-fa715ee3ce9abbc94edbJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 2V, positivesplash10-004i-9000000000-ace3c5f526d28fd24de9JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 3V, positivesplash10-004i-9000000000-ff7f922c2460adb6a10dJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 4V, positivesplash10-004i-9000000000-1d63aaaf9cbc6d3bb3b4JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 5V, positivesplash10-004j-9000000000-e9c74e7df728e016450cJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 6V, positivesplash10-002b-9000000000-d0963403f3a8ff9e576dJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 7V, positivesplash10-002b-9000000000-9e1d6b2e2b889232d610JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 8V, positivesplash10-0002-9000000000-e9824f68b2176db90d33JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 9V, positivesplash10-000t-9000000000-02329982bc7150d972bfJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - QqQ 10V, positivesplash10-000t-9000000000-216d8ece56b0a44e5289JSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-004i-9000000000-d961c3c14ec415e3141eJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0a6r-9000000000-67f73be970ba9f885c4aJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0a4i-9000000000-f2ccf0b88e0ad65ed4c6JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-004i-9000000000-7445713a5fe347bbc8b8JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-004i-9000000000-26e13242443efc1aa846JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4i-9000000000-6ba976b949118cd0a86aJSpectraViewer
MSMass Spectrum (Electron Ionization)splash10-001i-9000000000-2885890e3bb8c015742fJSpectraViewer | MoNA
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableJSpectraViewer
Toxicity Profile
Route of ExposureOral (30) ; dermal (30)
Mechanism of ToxicityGlycolic acid's toxicity is due to its metabolism to oxalic acid. Glycolic and oxalic acid, along with excess lactic acid, are responsible for the anion gap metabolic acidosis. Oxalic acid readily precipitates with calcium to form insoluble calcium oxalate crystals. Tissue injury is caused by widespread deposition of oxalate crystals and the toxic effects of glycolic acid. (1, 2)
MetabolismThe main path of the degradation of glycolic acid is to glyoxylic acid. This reaction is mediated by lactic dehydrogenase or glycolic acid oxidase. Once glyoxylic acid is formed, it is apparently degraded very rapidly to a variety of products, a few of which have been observed. Its breakdown to 2-hydroxy-3-oxoadipate it is thought, is mediated by thiamine pyrophosphate in the presence of magnesium ions. The formation of glycine involves pyridoxal phosphate and glyoxylate transaminase, whereas the formation of carbon dioxide and water via formic acid apparently involves coenzyme A (CoA) and flavin mononucleotides. (25)
Toxicity ValuesLD50: 1950 mg/kg (Oral, Rat) (3) LD50: 1000 mg/kg (Intravenous, Cat) (4) LC50: 7.7-14 mg/L over 4 hours (Inhalation, Rat) (4)
Lethal DoseNot Available
Carcinogenicity (IARC Classification)No indication of carcinogenicity to humans (not listed by IARC).
Uses/SourcesDue to its excellent capability to penetrate skin, glycolic acid finds applications in skin care products, most often as a chemical peel. It may reduce wrinkles, acne scarring, hyperpigmentation and improve many other skin conditions, including actinic keratosis, hyperkeratosis, and seborrheic keratosis. Glycolic acid is also a useful intermediate for organic synthesis and finds employment in the textile industry as a dyeing and tanning agent, in food processing as a flavoring agent and as a preservative. Glycolic acid is often included into emulsion polymers, solvents and additives for ink and paint in order to improve flow properties and impart gloss. (30)
Minimum Risk LevelNot Available
Health EffectsGlycolic acid metabolizes to oxalic acid, which reacts with calcium and forms calcium oxalate crystals in the kidney. This can cause kidney injury, leading to acute kidney failure. (31) Chronically high levels of glycolic acid are associated with the inborn error of metabolism known as Type I primary hyperoxaluria. Oxalate stones in primary hyperoxaluria tend to be severe, resulting in relatively early kidney damage (before age 20), which impairs the excretion of oxalate leading to a further acceleration in accumulation of oxalate in the body. After the development of renal failure patients may develop oxalate deposits in the bones, joints and bone marrow. Severe cases may develop haematological problems such as anaemia and thrombocytopaenia. The deposition of oxalate in the body is sometimes called "oxalosis" to be distinguished from "oxaluria" which refers to oxalate in the urine.
SymptomsGlycolic acid is a strong irritant. Accumulation of glycolic acid and its metabolite, oxalic acid, causes tachycardia, hypertension, hyperventilation, and metabolic acidosis. (31, 30)
TreatmentChronic Exposure: In some patients with primary hyperoxaluria type 1, pyridoxine treatment (vitamin B6) may decrease oxalate excretion and prevent kidney stone formation. Acute Exposure: EYES: irrigate opened eyes for several minutes under running water. INGESTION: do not induce vomiting. Rinse mouth with water (never give anything by mouth to an unconscious person). Seek immediate medical advice.
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDDB03085
HMDB IDHMDB00115
PubChem Compound ID757
ChEMBL IDCHEMBL252557
ChemSpider ID737
KEGG IDC00160
UniProt IDNot Available
OMIM ID259900 , 260000
ChEBI ID29805
BioCyc IDGLYCOLLATE
CTD IDNot Available
Stitch IDNot Available
PDB IDGOA
ACToR IDNot Available
Wikipedia LinkGlycolic_acid
References
Synthesis Reference

David Y. Tang, Arthur M. Foster, “(3-Trifluoromethylphenyl)-alpha-hydroxyacetic acid and process for preparation.” U.S. Patent US4296244, issued January, 1977.

MSDSLink
General References
  1. Yamamoto N, Naraparaju VR: Vitamin D3-binding protein as a precursor for macrophage activating factor in the inflammation-primed macrophage activation cascade in rats. Cell Immunol. 1996 Jun 15;170(2):161-7. [8660814 ]
  2. Yamamoto N, Naraparaju VR: Role of vitamin D3-binding protein in activation of mouse macrophages. J Immunol. 1996 Aug 15;157(4):1744-9. [8759764 ]
  3. de Leon J, Tracy J, McCann E, McGrory A, Diaz FJ: Schizophrenia and tobacco smoking: a replication study in another US psychiatric hospital. Schizophr Res. 2002 Jul 1;56(1-2):55-65. [12084420 ]
  4. Haskell CF, Kennedy DO, Wesnes KA, Milne AL, Scholey AB: A double-blind, placebo-controlled, multi-dose evaluation of the acute behavioural effects of guarana in humans. J Psychopharmacol. 2007 Jan;21(1):65-70. Epub 2006 Mar 13. [16533867 ]
  5. Horikoshi T, Matsumoto M, Usuki A, Igarashi S, Hikima R, Uchiwa H, Hayashi S, Brysk MM, Ichihashi M, Funasaka Y: Effects of glycolic acid on desquamation-regulating proteinases in human stratum corneum. Exp Dermatol. 2005 Jan;14(1):34-40. [15660917 ]
  6. Shoemaker JD, Elliott WH: Automated screening of urine samples for carbohydrates, organic and amino acids after treatment with urease. J Chromatogr. 1991 Jan 2;562(1-2):125-38. [2026685 ]
  7. DiNardo JC, Grove GL, Moy LS: Clinical and histological effects of glycolic acid at different concentrations and pH levels. Dermatol Surg. 1996 May;22(5):421-4. [8634803 ]
  8. Marangella M, Petrarulo M, Bianco O, Vitale C, Finocchiaro P, Linari F: Glycolate determination detects type I primary hyperoxaluria in dialysis patients. Kidney Int. 1991 Jan;39(1):149-54. [2002628 ]
  9. Tsiafoulis CG, Prodromidis MI, Karayannis MI: Development of amperometric biosensors for the determination of glycolic acid in real samples. Anal Chem. 2002 Jan 1;74(1):132-9. [11795781 ]
  10. Porter WH, Rutter PW, Yao HH: Simultaneous determination of ethylene glycol and glycolic acid in serum by gas chromatography-mass spectrometry. J Anal Toxicol. 1999 Nov-Dec;23(7):591-7. [10595845 ]
  11. Jacobsen D, Hewlett TP, Webb R, Brown ST, Ordinario AT, McMartin KE: Ethylene glycol intoxication: evaluation of kinetics and crystalluria. Am J Med. 1988 Jan;84(1):145-52. [3337119 ]
  12. Guneral F, Bachmann C: Age-related reference values for urinary organic acids in a healthy Turkish pediatric population. Clin Chem. 1994 Jun;40(6):862-6. [8087979 ]
  13. Bernstein EF, Lee J, Brown DB, Yu R, Van Scott E: Glycolic acid treatment increases type I collagen mRNA and hyaluronic acid content of human skin. Dermatol Surg. 2001 May;27(5):429-33. [11359487 ]
  14. Leumann EP, Dietl A, Matasovic A: Urinary oxalate and glycolate excretion in healthy infants and children. Pediatr Nephrol. 1990 Sep;4(5):493-7. [2242313 ]
  15. Booth ED, Dofferhoff O, Boogaard PJ, Watson WP: Comparison of the metabolism of ethylene glycol and glycolic acid in vitro by precision-cut tissue slices from female rat, rabbit and human liver. Xenobiotica. 2004 Jan;34(1):31-48. [14742135 ]
  16. Mahul P, Molliex S, Auboyer C, Levigne F, Jospe R, Dumont A, Gilloz A: [Neurotoxic role of glycocolle and derivatives in transurethral resection of the prostate]. Ann Fr Anesth Reanim. 1993;12(5):512-4. [8311360 ]
  17. Hoffmann GF, Meier-Augenstein W, Stockler S, Surtees R, Rating D, Nyhan WL: Physiology and pathophysiology of organic acids in cerebrospinal fluid. J Inherit Metab Dis. 1993;16(4):648-69. [8412012 ]
  18. Marangella M, Petrarulo M, Vitale C, Cosseddu D, Linari F: Plasma and urine glycolate assays for differentiating the hyperoxaluria syndromes. J Urol. 1992 Sep;148(3 Pt 2):986-9. [1507356 ]
  19. Effendy I, Kwangsukstith C, Lee JY, Maibach HI: Functional changes in human stratum corneum induced by topical glycolic acid: comparison with all-trans retinoic acid. Acta Derm Venereol. 1995 Nov;75(6):455-8. [8651024 ]
  20. Pien K, van Vlem B, van Coster R, Dacremont G, Piette M: An inherited metabolic disorder presenting as ethylene glycol intoxication in a young adult. Am J Forensic Med Pathol. 2002 Mar;23(1):96-100. [11953504 ]
  21. Dietzen DJ, Wilhite TR, Kenagy DN, Milliner DS, Smith CH, Landt M: Extraction of glyceric and glycolic acids from urine with tetrahydrofuran: utility in detection of primary hyperoxaluria. Clin Chem. 1997 Aug;43(8 Pt 1):1315-20. [9267307 ]
  22. Newman N, Newman A, Moy LS, Babapour R, Harris AG, Moy RL: Clinical improvement of photoaged skin with 50% glycolic acid. A double-blind vehicle-controlled study. Dermatol Surg. 1996 May;22(5):455-60. [8634809 ]
  23. Roe FJ: Perspectives in carbohydrate toxicology with special reference to carcinogenicity. Swed Dent J. 1984;8(3):99-111. [6592775 ]
  24. Porter WH, Rutter PW, Bush BA, Pappas AA, Dunnington JE: Ethylene glycol toxicity: the role of serum glycolic acid in hemodialysis. J Toxicol Clin Toxicol. 2001;39(6):607-15. [11762669 ]
  25. Bingham, E, Cohrssen, B, and Powell, CH (2001). Patty's Toxicology Volumes 1-9. 5th ed. New York, N.Y: John Wiley & Sons.
  26. Olson, KR (ed) (1999). Poisoning & Drug Overdose. 3rd edition. New York, NY: Lange Medical Books/McGraw-Hill.
  27. Gilman AG, Goodman LS, and Gilman A (eds) (1980). Goodman and Gilman's The Pharmacological Basis of Therapeutics. 6th ed. New York, NY: Macmillan Publishing Co., Inc.
  28. Sax NI (1984). Dangerous Properties of Industrial Materials. 6th ed. New York, NY: Van Nostrand Reinhold.
  29. European Chemicals Bureau (2000). IUCLID Dataset, Glycollic acid (79-14-1).
  30. Wikipedia. Glycolic acid. Last Updated 27 October 2009, [Link]
  31. Wikidoc. Ethylene glycol. Last Updated 11 June 2009. [Link]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available

Targets

General Function:
Protein homodimerization activity
Specific Function:
Catalyzes the rate-limiting step of the oxidative pentose-phosphate pathway, which represents a route for the dissimilation of carbohydrates besides glycolysis. The main function of this enzyme is to provide reducing power (NADPH) and pentose phosphates for fatty acid and nucleic acid synthesis.
Gene Name:
G6PD
Uniprot ID:
P11413
Molecular Weight:
59256.31 Da
References
  1. Overington JP, Al-Lazikani B, Hopkins AL: How many drug targets are there? Nat Rev Drug Discov. 2006 Dec;5(12):993-6. [17139284 ]
  2. Imming P, Sinning C, Meyer A: Drugs, their targets and the nature and number of drug targets. Nat Rev Drug Discov. 2006 Oct;5(10):821-34. [17016423 ]