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Record Information
Version3.6
Creation Date2005-11-16 15:48:42 UTC
Update Date2016-06-10 21:22:25 UTC
HMDB IDHMDB00784
Secondary Accession NumbersNone
Metabolite Identification
Common NameAzelaic acid
DescriptionAzelaic acid (AZA) is a naturally occurring saturated nine-carbon dicarboxylic acid (COOH (CH2)7-COOH). It possesses a variety of biological actions both in vitro and in vivo. Interest in the biological activity of AZA arose originally out of studies of skin surface lipids and the pathogenesis of hypochromia in pityriasis versicolor infection. Later, it was shown that Pityrosporum can oxidize unsaturated fatty acids to C8-C12 dicarboxylic acids that are cornpetitive inhibitors of tyrosinase in vitro. Azelaic acid was chosen for further investigation and development of a new topical drug for treating hyperpigmentary disorders for the following reasons: it possesses a middle-range of antityrosinase activity, is inexpensive, and more soluble to be incorporated into a base cream than other dicarboxylic acids. Azelaic acid is another option for the topical treatment of mild to moderate inflammatory acne vulgaris. It offers effectiveness similar to that of other agents without the systemic side effects of oral antibiotics or the allergic sensitization of topical benzoyl peroxide and with less irritation than tretinoin. Azelaic acid is less expensive than certain other prescription acne preparations, but it is much more expensive than nonprescription benzoyl peroxide preparations. Whether it is safe and effective when used in combination with other agents is not known. (PMID: 7737781 , 8961845 ).
Structure
Thumb
Synonyms
ValueSource
1,7-DicarboxyheptaneChEBI
1,7-Heptanedicarboxylic acidChEBI
1,9-Nonanedioic acidChEBI
Acide azelaiqueChEBI
Acidum azelaicumChEBI
Anchoic acidChEBI
AzelainsaeureChEBI
AzelexChEBI
FinaceaChEBI
Lepargylic acidChEBI
N-Nonanedioic acidChEBI
NonandisaeureChEBI
Nonanedioic acidChEBI
SkinorenChEBI
AzelaateGenerator
1,7-HeptanedicarboxylateGenerator
1,9-NonanedioateGenerator
AnchoateGenerator
LepargylateGenerator
N-NonanedioateGenerator
NonanedioateGenerator
Azalaic acidHMDB
AzelaicacidtechHMDB
Azelainic acidHMDB
AzelateHMDB
Emerox 1110HMDB
Emerox 1144HMDB
Emery'S L-110HMDB
FinevinHMDB
Heptanedicarboxylic acidHMDB
Nonanedioic acid azelaic acidHMDB
Nonanedioic acid homopolymerHMDB
Poly(azelaic anhydride)HMDB
Polyazelaic anhydrideHMDB
SkinoremHMDB
Chemical FormulaC9H16O4
Average Molecular Weight188.2209
Monoisotopic Molecular Weight188.104859
IUPAC Namenonanedioic acid
Traditional Nameazelaic acid
CAS Registry Number123-99-9
SMILES
OC(=O)CCCCCCCC(O)=O
InChI Identifier
InChI=1S/C9H16O4/c10-8(11)6-4-2-1-3-5-7-9(12)13/h1-7H2,(H,10,11)(H,12,13)
InChI KeyInChIKey=BDJRBEYXGGNYIS-UHFFFAOYSA-N
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as medium-chain fatty acids. These are fatty acids with an aliphatic tail that contains between 4 and 12 carbon atoms.
KingdomOrganic compounds
Super ClassLipids and lipid-like molecules
ClassFatty Acyls
Sub ClassFatty acids and conjugates
Direct ParentMedium-chain fatty acids
Alternative Parents
Substituents
  • Medium-chain fatty acid
  • Dicarboxylic acid or derivatives
  • Carboxylic acid
  • Carboxylic acid derivative
  • Hydrocarbon derivative
  • Organooxygen compound
  • Carbonyl group
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors
Ontology
StatusDetected and Quantified
Origin
  • Endogenous
BiofunctionNot Available
ApplicationNot Available
Cellular locationsNot Available
Physical Properties
StateSolid
Experimental Properties
PropertyValueReference
Melting Point106.5 °CNot Available
Boiling PointNot AvailableNot Available
Water Solubility2.4 mg/mLNot Available
LogP1.57HANSCH,C ET AL. (1995)
Predicted Properties
PropertyValueSource
Water Solubility2.28 mg/mLALOGPS
logP1.37ALOGPS
logP1.82ChemAxon
logS-1.9ALOGPS
pKa (Strongest Acidic)4.15ChemAxon
Physiological Charge-2ChemAxon
Hydrogen Acceptor Count4ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area74.6 Å2ChemAxon
Rotatable Bond Count8ChemAxon
Refractivity46.54 m3·mol-1ChemAxon
Polarizability20.5 Å3ChemAxon
Number of Rings0ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash Key
GC-MSGC-MS Spectrum - GC-MS (2 TMS)splash10-0v0r-4920000000-5a3ed693b1c4083f1f15View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Negative (Annotated)splash10-000i-0900000000-a118e433f0bd27a95b89View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Negative (Annotated)splash10-006t-9600000000-93b3a375b722791cb5c9View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Negative (Annotated)splash10-052k-9500000000-6b069f2fed947651b284View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 10V, Negativesplash10-000i-0900000000-7980b5eadcca6ee1eaddView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 20V, Negativesplash10-004i-0900000000-462585874f7661d40d5bView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 30V, Negativesplash10-004j-4900000000-0f65eeeed8c8a6ff3cc9View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 40V, Negativesplash10-0002-9300000000-d654ca3c764066f98358View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 50V, Negativesplash10-0002-9000000000-60a08bb384f2b4cbfca8View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-00dr-0900000000-b1b7c1ab57d58a2405a8View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-00g3-2900000000-d0ba7fbbe987efa4c818View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-05qd-9100000000-8d65a19b998d18ad08acView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-000i-0900000000-a7edc3ac66d27685b9d1View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-00kr-1900000000-c56b9d972f88c58dc65bView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4l-9300000000-47cbefe19a788d7f36b9View in MoNA
MSMass Spectrum (Electron Ionization)splash10-06rx-9100000000-6db2acb47ad4c6163063View in MoNA
1D NMR1H NMR SpectrumNot Available
1D NMR1H NMR SpectrumNot Available
1D NMR13C NMR SpectrumNot Available
2D NMR[1H,13C] 2D NMR SpectrumNot Available
Biological Properties
Cellular LocationsNot Available
Biofluid Locations
  • Blood
  • Breast Milk
  • Cerebrospinal Fluid (CSF)
  • Feces
  • Saliva
  • Urine
Tissue Location
  • Prostate
  • Skin
PathwaysNot Available
Normal Concentrations
BiofluidStatusValueAgeSexConditionReferenceDetails
BloodDetected and Quantified27.0 (0.0-58.0) uMAdult (>18 years old)BothNormal details
Breast MilkDetected and Quantified101 +/- 72.5 uMAdult (>18 years old)Female
Normal
details
Cerebrospinal Fluid (CSF)Detected and Quantified17.0 +/- 17.0 uMAdult (>18 years old)Not SpecifiedNormal details
FecesDetected but not QuantifiedNot ApplicableNot SpecifiedNot Specified
Normal
details
FecesDetected but not QuantifiedNot ApplicableNot SpecifiedNot Specified
Normal
details
SalivaDetected and Quantified0.0648 +/- 0.127 uMAdult (>18 years old)Male
Normal
    • Sugimoto et al. (...
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Male
Normal
details
SalivaDetected and Quantified1.69 +/- 0.876 uMAdult (>18 years old)Female
Normal
    • Sugimoto et al. (...
details
SalivaDetected and Quantified1.73 +/- 1.02 uMAdult (>18 years old)Female
Normal
    • Sugimoto et al. (...
details
SalivaDetected and Quantified0.221 +/- 0.218 uMAdult (>18 years old)Female
Normal
    • Sugimoto et al. (...
details
SalivaDetected and Quantified2.06 +/- 1.85 uMAdult (>18 years old)Female
Normal
    • Sugimoto et al. (...
details
SalivaDetected and Quantified2.74 +/- 1.71 uMAdult (>18 years old)Both
Normal
    • Sugimoto et al. (...
details
UrineDetected and Quantified2.5 (0.1-12.3) umol/mmol creatinineNewborn (0-30 days old)BothNormal details
UrineDetected and Quantified3.6 (0.1-4.4) umol/mmol creatinineInfant (0-1 year old)BothNormal details
UrineDetected and Quantified4.3 (1.0-11.7) umol/mmol creatinineChildren (1-13 years old)Both
Normal
details
UrineDetected and Quantified3.7 (0.6-17.6) umol/mmol creatinineAdolescent (13-18 years old)Both
Normal
details
UrineDetected but not QuantifiedNot ApplicableAdult (>18 years old)BothNormal details
UrineDetected and Quantified2.21 +/- 1.67 umol/mmol creatinineAdult (>18 years old)BothNot Available details
UrineDetected and Quantified8.033 +/- 4.649 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
Normal
    • Mordechai, Hien, ...
details
UrineDetected and Quantified0.50-1.2 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected but not QuantifiedNot ApplicableAdult (>18 years old)BothNormal details
UrineDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Normal
details
UrineDetected and Quantified4.8 (1.3-15) umol/mmol creatinineAdult (>18 years old)BothNormal details
UrineDetected and Quantified5.382 +/- 1.998 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
Normal
    • Mordechai, Hien, ...
details
UrineDetected and Quantified0.45-0.81 umol/mmol creatinineAdult (>18 years old)MaleNormal details
UrineDetected and Quantified2.8 (1.8-4.8) umol/mmol creatinineAdult (>18 years old)Both
Normal
details
UrineDetected and Quantified1.9 (1.2-3.2) umol/mmol creatinineAdult (>18 years old)Both
Normal
details
Abnormal Concentrations
BiofluidStatusValueAgeSexConditionReferenceDetails
BloodDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
gastric cancer
details
BloodDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
superficial gastric cancer
details
UrineDetected and Quantified7.782 +/- 5.227 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
Eosinophilic esophagitis
    • Mordechai, Hien, ...
details
UrineDetected and Quantified10.726 +/- 11.681 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
Gastroesophageal reflux disease
    • Mordechai, Hien, ...
details
UrineDetected and Quantified4.791 +/- 3.255 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
Eosinophilic esophagitis
    • Mordechai, Hien, ...
details
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDDB00548
DrugBank Metabolite IDNot Available
Phenol Explorer Compound IDNot Available
Phenol Explorer Metabolite IDNot Available
FoodDB IDFDB012192
KNApSAcK IDNot Available
Chemspider ID2179
KEGG Compound IDC08261
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNonanedioic acid
NuGOwiki LinkHMDB00784
Metagene LinkHMDB00784
METLIN ID5750
PubChem Compound2266
PDB IDAZ1
ChEBI ID48131
References
Synthesis ReferenceChen, Song; Yan, Jinlong. Synthesis of azelaic acid by chemical oxidation with oleic acid. Pige Huagong (2003), 20(6), 31-35.
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Sreekumar A, Poisson LM, Rajendiran TM, Khan AP, Cao Q, Yu J, Laxman B, Mehra R, Lonigro RJ, Li Y, Nyati MK, Ahsan A, Kalyana-Sundaram S, Han B, Cao X, Byun J, Omenn GS, Ghosh D, Pennathur S, Alexander DC, Berger A, Shuster JR, Wei JT, Varambally S, Beecher C, Chinnaiyan AM: Metabolomic profiles delineate potential role for sarcosine in prostate cancer progression. Nature. 2009 Feb 12;457(7231):910-4. [19212411 ]
  2. 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 ]
  3. Mayer-da-Silva A, Gollnick H, Detmar M, Gassmuller J, Parry A, Muller R, Orfanos CE: Effects of azelaic acid on sebaceous gland, sebum excretion rate and keratinization pattern in human skin. An in vivo and in vitro study. Acta Derm Venereol Suppl (Stockh). 1989;143:20-30. [2475995 ]
  4. Hermanns JF, Petit L, Martalo O, Pierard-Franchimont C, Cauwenbergh G, Pierard GE: Unraveling the patterns of subclinical pheomelanin-enriched facial hyperpigmentation: effect of depigmenting agents. Dermatology. 2000;201(2):118-22. [11053913 ]
  5. Korman SH, Mandel H, Gutman A: Characteristic urine organic acid profile in peroxisomal biogenesis disorders. J Inherit Metab Dis. 2000 Jun;23(4):425-8. [10896310 ]
  6. Rocamora V, Puig L, Romani J, de Moragas JM: Amelanotic lentigo maligna melanoma: report of a case and review of the literature. Cutis. 1999 Jul;64(1):53-6. [10431675 ]
  7. Russell JJ: Topical therapy for acne. Am Fam Physician. 2000 Jan 15;61(2):357-66. [10670502 ]
  8. Webster G: Combination azelaic acid therapy for acne vulgaris. J Am Acad Dermatol. 2000 Aug;43(2 Pt 3):S47-50. [10898830 ]
  9. Del Rosso JQ: A status report on the medical management of rosacea: focus on topical therapies. Cutis. 2002 Nov;70(5):271-5. [12469780 ]
  10. Liao DC: Management of acne. J Fam Pract. 2003 Jan;52(1):43-51. [12540312 ]
  11. Del Rosso JQ: Medical treatment of rosacea with emphasis on topical therapies. Expert Opin Pharmacother. 2004 Jan;5(1):5-13. [14680431 ]
  12. Wolf JE Jr: The role of topical metronidazole in the treatment of rosacea. Cutis. 2004 Jan;73(1 Suppl):19-28. [14959942 ]
  13. Frampton JE, Wagstaff AJ: Azelaic acid 15% gel: in the treatment of papulopustular rosacea. Am J Clin Dermatol. 2004;5(1):57-64. [14979745 ]
  14. Halder RM, Richards GM: Management of dyschromias in ethnic skin. Dermatol Ther. 2004;17(2):151-7. [15113282 ]
  15. Halder RM, Richards GM: Topical agents used in the management of hyperpigmentation. Skin Therapy Lett. 2004 Jun-Jul;9(6):1-3. [15334278 ]
  16. Lindow KB: Rosacea. An overview of diagnosis and management. Adv Nurse Pract. 2004 Dec;12(12):27-32. [15615217 ]
  17. Cayce KA, McMichael AJ, Feldman SR: Hyperpigmentation: an overview of the common afflictions. Dermatol Nurs. 2004 Oct;16(5):401-6, 413-6; quiz 417. [15624705 ]
  18. Wolf JE Jr: Present and future rosacea therapy. Cutis. 2005 Mar;75(3 Suppl):4-7; discussion 33-6. [15810803 ]
  19. van Zuuren EJ, Graber MA: The rigor of trials evaluating Rosacea treatments. Cutis. 2005 Mar;75(3 Suppl):13-6; discussion 33-6. [15810805 ]
  20. Purdy S: Acne vulgaris. Clin Evid. 2005 Jun;(13):2038-59. [16135322 ]
  21. Roebuck HL: Face up to rosacea. Nurse Pract. 2005 Sep;30(9):24-30, 35; quiz 36-7. [16151303 ]
  22. Callender VD: Considerations for treating acne in ethnic skin. Cutis. 2005 Aug;76(2 Suppl):19-23. [16164153 ]
  23. Nally JB, Berson DS: Topical therapies for rosacea. J Drugs Dermatol. 2006 Jan;5(1):23-6. [16468288 ]
  24. Fleischer AB Jr: The evolution of azelaic acid. Cutis. 2006 Feb;77(2 Suppl):4-6. [16566281 ]
  25. Draelos ZD: The rationale for advancing the formulation of azelaic acid vehicles. Cutis. 2006 Feb;77(2 Suppl):7-11. [16566282 ]
  26. Elewski B, Thiboutot D: A clinical overview of azelaic acid. Cutis. 2006 Feb;77(2 Suppl):12-6. [16566283 ]
  27. Del Rosso JQ: The use of topical azelaic acid for common skin disorders other than inflammatory rosacea. Cutis. 2006 Feb;77(2 Suppl):22-4. [16566285 ]
  28. Worret WI, Fluhr JW: [Acne therapy with topical benzoyl peroxide, antibiotics and azelaic acid] J Dtsch Dermatol Ges. 2006 Apr;4(4):293-300. [16638058 ]
  29. Liu RH, Smith MK, Basta SA, Farmer ER: Azelaic acid in the treatment of papulopustular rosacea: a systematic review of randomized controlled trials. Arch Dermatol. 2006 Aug;142(8):1047-52. [16924055 ]
  30. Goodman G: Managing acne vulgaris effectively. Aust Fam Physician. 2006 Sep;35(9):705-9. [16969442 ]
  31. Purdy S: Acne vulgaris. Clin Evid. 2006 Jun;(15):2183-201. [16973084 ]
  32. Gupta AK, Gover MD, Nouri K, Taylor S: The treatment of melasma: a review of clinical trials. J Am Acad Dermatol. 2006 Dec;55(6):1048-65. Epub 2006 Sep 28. [17097400 ]
  33. Fitton A, Goa KL: Azelaic acid. A review of its pharmacological properties and therapeutic efficacy in acne and hyperpigmentary skin disorders. Drugs. 1991 May;41(5):780-98. [1712709 ]
  34. van Zuuren EJ, Gupta AK, Gover MD, Graber M, Hollis S: Systematic review of rosacea treatments. J Am Acad Dermatol. 2007 Jan;56(1):107-15. Epub 2006 Nov 7. [17190628 ]
  35. Gupta AK, Gover MD: Azelaic acid (15% gel) in the treatment of acne rosacea. Int J Dermatol. 2007 May;46(5):533-8. [17472690 ]
  36. Nguyen QH, Bui TP: Azelaic acid: pharmacokinetic and pharmacodynamic properties and its therapeutic role in hyperpigmentary disorders and acne. Int J Dermatol. 1995 Feb;34(2):75-84. [7737781 ]
  37. Mackrides PS, Shaughnessy AF: Azelaic acid therapy for acne. Am Fam Physician. 1996 Dec;54(8):2457-9. [8961845 ]

Enzymes

General function:
Involved in oxidoreductase activity
Specific function:
This is a copper-containing oxidase that functions in the formation of pigments such as melanins and other polyphenolic compounds. Catalyzes the rate-limiting conversions of tyrosine to DOPA, DOPA to DOPA-quinone and possibly 5,6-dihydroxyindole to indole-5,6 quinone.
Gene Name:
TYR
Uniprot ID:
P14679
Molecular weight:
60392.69
References
  1. Schallreuter KU, Wood JW: A possible mechanism of action for azelaic acid in the human epidermis. Arch Dermatol Res. 1990;282(3):168-71. [2114832 ]
  2. Nazzaro-Porro M: Azelaic acid. J Am Acad Dermatol. 1987 Dec;17(6):1033-41. [2963038 ]
  3. Picardo M, Passi S, Sirianni MC, Fiorilli M, Russo GD, Cortesi E, Barile G, Breathnach AS, Nazzaro-Porro M: Activity of azelaic acid on cultures of lymphoma- and leukemia-derived cell lines, normal resting and stimulated lymphocytes and 3T3 fibroblasts. Biochem Pharmacol. 1985 May 15;34(10):1653-8. [4004885 ]
  4. Nazzaro-Porro M, Passi S, Balus L, Breathnach A, Martin B, Morpurgo G: Effect of dicarboxylic acids on lentigo maligna. J Invest Dermatol. 1979 Jun;72(6):296-305. [448162 ]
General function:
Involved in oxidoreductase activity
Specific function:
Efficiently catalyzes the reduction of progesterone, androstenedione, 17-alpha-hydroxyprogesterone and testosterone to 5-beta-reduced metabolites. The bile acid intermediates 7-alpha,12-alpha-dihydroxy-4-cholesten-3-one and 7-alpha-hydroxy-4-cholesten-3-one can also act as substrates.
Gene Name:
AKR1D1
Uniprot ID:
P51857
Molecular weight:
32889.38
References
  1. Stamatiadis D, Bulteau-Portois MC, Mowszowicz I: Inhibition of 5 alpha-reductase activity in human skin by zinc and azelaic acid. Br J Dermatol. 1988 Nov;119(5):627-32. [3207614 ]
General function:
Involved in 3-oxo-5-alpha-steroid 4-dehydrogenase activity
Specific function:
Converts testosterone (T) into 5-alpha-dihydrotestosterone (DHT) and progesterone or corticosterone into their corresponding 5-alpha-3-oxosteroids. It plays a central role in sexual differentiation and androgen physiology.
Gene Name:
SRD5A2
Uniprot ID:
P31213
Molecular weight:
28407.035
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 ]
  3. Stamatiadis D, Bulteau-Portois MC, Mowszowicz I: Inhibition of 5 alpha-reductase activity in human skin by zinc and azelaic acid. Br J Dermatol. 1988 Nov;119(5):627-32. [3207614 ]