Zaprinast

Zaprinast
Names
	IUPAC name 5-(2-Propoxyphenyl)-1H-[1,2,3]triazolo[4,5-d]pyrimidin-7(4H)-one
	Other names M&B 22,948
Identifiers
CAS Number	37762-06-4 ;
3D model (JSmol)	Interactive image;
ChEMBL	ChEMBL28079 ;
ChemSpider	5520 ;
ECHA InfoCard	100.048.760
IUPHAR/BPS	2919;
PubChem CID	5722;
UNII	GXT25D5DS0 ;
CompTox Dashboard (EPA)	DTXSID8045224 ;
	InChI InChI=1S/C13H13N5O2/c1-2-7-20-9-6-4-3-5-8(9)11-14-12-10(13(19)15-11)16-18-17-12/h3-6H,2,7H2,1H3,(H2,14,15,16,17,18,19) Key: REZGGXNDEMKIQB-UHFFFAOYSA-N ;
	SMILES O=C1C2=C(N=NN2)NC(C3=CC=CC=C3OCCC)=N1;
Properties
Chemical formula	C13H13N5O2
Molar mass	271.280 g·mol−1
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Zaprinast was an unsuccessful clinical drug candidate that was a precursor to the chemically related PDE5 inhibitors, such as sildenafil (Viagra), which successfully reached the market. It is a phosphodiesterase inhibitor, selective for the subtypes PDE5, PDE6, PDE9 and PDE11. IC₅₀ values are 0.76, 0.15, 29.0, and 12.0 μM, respectively.

Zaprinast inhibits the growth of asexual blood-stage malaria parasites (P. falciparum) in vitro with an ED₅₀ value of 35 μM, and inhibits PfPDE1, a P. falciparum cGMP-specific phosphodiesterase, with an IC₅₀ value of 3.8 μM.

Zaprinast has also been shown to activate the orphan G-protein coupled receptor known as GPR35, both in rats and humans, and to inhibit the mitochondrial pyruvate carrier.