WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 524404

CAS#: 794568-92-6

Description: BAY 73-6691 is a drug developed by Bayer for the treatment of Alzheimer's disease. It was the first compound developed that acts as a phosphodiesterase inhibitor selective for the PDE9A subtype. The PDE9A enzyme is expressed primarily in the brain, with high concentrations in the cerebellum, neocortex, striatum, and hippocampus, and acts to limit the cGMP-mediated signal transduction which occurs following glutamate binding to NMDA receptors.

Price and Availability




BAY-73-6691, purity > 98%, is not in stock, may be available through custom synthesis. For cost-effective reason, minimum 1 gram order is requested. The product will be characterized by NMR, HPLC and MS analysis. Purity (HPLC) is usually >98%. CoA, QC data, MSDS will be provided when product is successfully made. The estimated lead time is 2-3 months. Please send email to to inquire quote.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 524404
Name: BAY-73-6691
CAS#: 794568-92-6
Chemical Formula: C15H12ClF3N4O
Exact Mass: 356.06517
Molecular Weight: 356.73
Elemental Analysis: C, 50.50; H, 3.39; Cl, 9.94; F, 15.98; N, 15.71; O, 4.49

Synonym: BAY-73-6691; BAY736691; BAY73-6691; UNII-80ZTV3INTW; (R)-Bay-73-6691;

IUPAC/Chemical Name: 4H-Pyrazolo(3,4-d)pyrimidin-4-one, 1-(2-chlorophenyl)-1,5-dihydro-6-((2R)-3,3,3-trifluoro-2-methylpropyl)-


InChi Code: InChI=1S/C15H12ClF3N4O/c1-8(15(17,18)19)6-12-21-13-9(14(24)22-12)7-20-23(13)11-5-3-2-4-10(11)16/h2-5,7-8H,6H2,1H3,(H,21,22,24)/t8-/m1/s1

SMILES Code: C[C@H](Cc1[nH]c(=O)c2cnn(c2n1)c3ccccc3Cl)C(F)(F)F

Technical Data

Solid powder

>98% (or refer to the Certificate of Analysis)

Shipping Condition:
Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition:
Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Soluble in DMSO, not in water

Shelf Life:
>2 years if stored properly

Drug Formulation:
This drug may be formulated in DMSO

Stock Solution Storage:
0 - 4 C for short term (days to weeks), or -20 C for long term (months).

Harmonized System Code:


1: Li J, Liu CN, Wei N, Li XD, Liu YY, Yang R, Jia YJ. Protective effects of BAY 73-6691, a selective inhibitor of phosphodiesterase 9, on amyloid-β peptides-induced oxidative stress in in-vivo and in-vitro models of Alzheimer's disease. Brain Res. 2016 Apr 9. pii: S0006-8993(16)30204-9. doi: 10.1016/j.brainres.2016.04.011. [Epub ahead of print] PubMed PMID: 27071547.

2: da Silva FH, Pereira MN, Franco-Penteado CF, De Nucci G, Antunes E, Claudino MA. Phosphodiesterase-9 (PDE9) inhibition with BAY 73-6691 increases corpus cavernosum relaxations mediated by nitric oxide-cyclic GMP pathway in mice. Int J Impot Res. 2013 Mar-Apr;25(2):69-73. doi: 10.1038/ijir.2012.35. Epub 2012 Oct 4. PubMed PMID: 23034509.

3: van der Staay FJ, Rutten K, Bärfacker L, Devry J, Erb C, Heckroth H, Karthaus D, Tersteegen A, van Kampen M, Blokland A, Prickaerts J, Reymann KG, Schröder UH, Hendrix M. The novel selective PDE9 inhibitor BAY 73-6691 improves learning and memory in rodents. Neuropharmacology. 2008 Oct;55(5):908-18. doi: 10.1016/j.neuropharm.2008.07.005. Epub 2008 Jul 12. PubMed PMID: 18674549.