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Record Information
StatusExpected but not Quantified
Creation Date2012-09-06 15:16:50 UTC
Update Date2020-02-26 21:40:42 UTC
Secondary Accession Numbers
  • HMDB14958
Metabolite Identification
Common NameTadalafil
DescriptionTadalafil is an orally adminstered drug used to treat male erectile dysfunction (impotence). It is marketed worldwide under the brand name Cialis. It is a phosphodiesterase 5 (PDE5) inhibitor. Tadalafil's distinguishing pharmacologic feature is its longer half-life (17.5 hours) compared with Viagra and Levitra (4-5 hours). This longer half-life results in a longer duration of action and is, in part, responsible for the Cialis nickname of the 'weekend pill.' This longer half-life also is the basis of current investigation for tadalafil's use in pulmonary arterial hypertension as a once-daily therapy. [Wikipedia ]
(6R,12AR)-2,3,6,7,12,12a-hexahydro-2-methyl-6-(3,4-(methylenedioxy)phenyl) pyrazino(1',2':1,6)pyrido(3,4-b)indole-1,4-dioneChEBI
Chemical FormulaC22H19N3O4
Average Molecular Weight389.404
Monoisotopic Molecular Weight389.137556111
IUPAC Name(2R,8R)-2-(2H-1,3-benzodioxol-5-yl)-6-methyl-3,6,17-triazatetracyclo[³,⁸.0¹¹,¹⁶]heptadeca-1(10),11,13,15-tetraene-4,7-dione
Traditional Nametadalafil
CAS Registry Number171596-29-5
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as beta carbolines. Beta carbolines are compounds containing a 9H-pyrido[3,4-b]indole moiety.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
ClassIndoles and derivatives
Sub ClassPyridoindoles
Direct ParentBeta carbolines
Alternative Parents
  • Beta-carboline
  • Alpha-amino acid or derivatives
  • 3-alkylindole
  • Benzodioxole
  • Indole
  • 2,5-dioxopiperazine
  • Dioxopiperazine
  • N-methylpiperazine
  • N-alkylpiperazine
  • Benzenoid
  • Piperazine
  • 1,4-diazinane
  • Tertiary carboxylic acid amide
  • Pyrrole
  • Heteroaromatic compound
  • Carboxamide group
  • Lactam
  • Acetal
  • Carboxylic acid derivative
  • Oxacycle
  • Azacycle
  • Hydrocarbon derivative
  • Organic nitrogen compound
  • Organic oxide
  • Carbonyl group
  • Organopnictogen compound
  • Organic oxygen compound
  • Organooxygen compound
  • Organonitrogen compound
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External Descriptors

Biological location:


Industrial application:

Physical Properties
Experimental Properties
Melting Point301 - 302 °CNot Available
Boiling PointNot AvailableNot Available
Water Solubility0.25 g/LNot Available
LogP1.7Not Available
Predicted Properties
Water Solubility0.25 g/LALOGPS
pKa (Strongest Acidic)15.17ChemAxon
pKa (Strongest Basic)-4.2ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count4ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area74.87 ŲChemAxon
Rotatable Bond Count1ChemAxon
Refractivity104.08 m³·mol⁻¹ChemAxon
Polarizability40.92 ųChemAxon
Number of Rings6ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0006-3097000000-803ff86b2ce502e2bc83Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-qTof , Positivesplash10-02t9-2890000000-0be3708ad44a8a467cc5Spectrum
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , negativesplash10-03di-0090000000-c52485d22b5893fc60a2Spectrum
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , negativesplash10-03di-0090000000-2f6ad2194cd2932b0761Spectrum
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-0i0r-0291000000-a4ae40141abccfc86710Spectrum
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-0j59-0290000000-86095fe2d98833db9d0bSpectrum
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-0uy0-0429200000-641774545afc89315134Spectrum
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-0uy0-0429200000-f223c860e93cceeeacd8Spectrum
LC-MS/MSLC-MS/MS Spectrum - , positivesplash10-014i-0292000000-0563bdd5b0be8c1cfa47Spectrum
LC-MS/MSLC-MS/MS Spectrum - , positivesplash10-02t9-2890000000-0be3708ad44a8a467cc5Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0006-0009000000-cfa5abcf4ec76ea41d68Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0006-1019000000-59cc81b34404c6ecd167Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0006-0291000000-20d1a51d47c7345d5742Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-000i-2009000000-721840625f2b26eb19a7Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-052r-4019000000-5dff72997668963ef319Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-01pc-2191000000-f8bd70ef77444b35f09bSpectrum
Biological Properties
Cellular Locations
  • Cytoplasm
  • Membrane
Biospecimen Locations
  • Blood
  • Urine
Tissue LocationsNot Available
Normal Concentrations
BloodExpected but not QuantifiedNot QuantifiedNot AvailableNot AvailableTaking drug identified by DrugBank entry DB00820 details
UrineExpected but not QuantifiedNot QuantifiedNot AvailableNot AvailableTaking drug identified by DrugBank entry DB00820 details
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDDB00820
Phenol Explorer Compound IDNot Available
FooDB IDNot Available
KNApSAcK IDNot Available
Chemspider ID99301
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkTadalafil
METLIN IDNot Available
PubChem Compound110635
ChEBI ID71940
Food Biomarker OntologyNot Available
VMH IDNot Available
MarkerDB ID
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Guazzi M, Samaja M: The role of PDE5-inhibitors in cardiopulmonary disorders: from basic evidence to clinical development. Curr Med Chem. 2007;14(20):2181-91. [PubMed:17691956 ]
  2. Naeije R, Huez S: Expert opinion on available options treating pulmonary arterial hypertension. Expert Opin Pharmacother. 2007 Oct;8(14):2247-65. [PubMed:17927481 ]
  3. Burnett AL: Molecular pharmacotherapeutic targeting of PDE5 for preservation of penile health. J Androl. 2008 Jan-Feb;29(1):3-14. Epub 2007 Oct 17. [PubMed:17942972 ]


General function:
Involved in catalytic activity
Specific function:
Plays a role in signal transduction by regulating the intracellular concentration of cyclic nucleotides. This phosphodiesterase catalyzes the specific hydrolysis of cGMP to 5'-GMP.
Gene Name:
Uniprot ID:
Molecular weight:
  1. Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. [PubMed:11752352 ]
  2. Curran M, Keating G: Tadalafil. Drugs. 2003;63(20):2203-12; discussion 2213-4. [PubMed:14498756 ]
  3. Eardley I, Cartledge J: Tadalafil (Cialis) for men with erectile dysfunction. Int J Clin Pract. 2002 May;56(4):300-4. [PubMed:12074215 ]
  4. Montorsi F, Salonia A, Deho' F, Cestari A, Guazzoni G, Rigatti P, Stief C: Pharmacological management of erectile dysfunction. BJU Int. 2003 Mar;91(5):446-54. [PubMed:12603396 ]
  5. Rotella DP: Tadalafil Lilly ICOS. Curr Opin Investig Drugs. 2003 Jan;4(1):60-5. [PubMed:12625031 ]
  6. Roumeguere T, Sternon J, Schulman CC: [Erectile dysfunction and phosphodiesterase type 5 inhibitors]. Rev Med Brux. 2003 Jun;24(3):169-75. [PubMed:12891884 ]
  7. Zoraghi R, Francis SH, Corbin JD: Critical amino acids in phosphodiesterase-5 catalytic site that provide for high-affinity interaction with cyclic guanosine monophosphate and inhibitors. Biochemistry. 2007 Nov 27;46(47):13554-63. Epub 2007 Nov 3. [PubMed:17979301 ]
General function:
Involved in monooxygenase activity
Specific function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It performs a variety of oxidation reactions (e.g. caffeine 8-oxidation, omeprazole sulphoxidation, midazolam 1'-hydroxylation and midazolam 4-hydroxylation) of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. Acts as a 1,8-cineole 2-exo-monooxygenase. The enzyme also hydroxylates etoposide.
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  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256 ]
General function:
Involved in catalytic activity
Specific function:
Plays a role in signal transduction by regulating the intracellular concentration of cyclic nucleotides cAMP and cGMP. Catalyzes the hydrolysis of both cAMP and cGMP to 5'-AMP and 5'-GMP, respectively.
Gene Name:
Uniprot ID:
Molecular weight:
  1. Weeks JL 2nd, Corbin JD, Francis SH: Interactions between cyclic nucleotide phosphodiesterase 11 catalytic site and substrates or tadalafil and role of a critical Gln-869 hydrogen bond. J Pharmacol Exp Ther. 2009 Oct;331(1):133-41. doi: 10.1124/jpet.109.156935. Epub 2009 Jul 29. [PubMed:19641165 ]
  2. Weeks JL 2nd, Zoraghi R, Francis SH, Corbin JD: N-Terminal domain of phosphodiesterase-11A4 (PDE11A4) decreases affinity of the catalytic site for substrates and tadalafil, and is involved in oligomerization. Biochemistry. 2007 Sep 11;46(36):10353-64. Epub 2007 Aug 16. [PubMed:17696499 ]