5-Nitro-2-propoxyaniline, also known as P-4000 and Ultrasüss, is about 4,000 times the intensity of sucrose (hence its alternate name, P-4000). It is an orange solid that is only slightly soluble in water. It is stable in boiling water and dilute acids. 5-Nitro-2-propoxyaniline was once used as an artificial sweetener but has been banned in the United States because of its possible toxicity.

5-Nitro-2-propoxyaniline^[1]

Names
Preferred IUPAC name 5-Nitro-2-propoxyaniline
Identifiers
CAS Number	553-79-7 Y
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL322314 Y
ChemSpider	10647 Y
ECHA InfoCard	100.008.228
PubChem CID	11118
UNII	HDS42MR6BM Y
CompTox Dashboard (EPA)	DTXSID50203827
InChI InChI=1S/C9H12N2O3/c1-2-5-14-9-4-3-7(11(12)13)6-8(9)10/h3-4,6H,2,5,10H2,1H3 Y Key: RXQCEGOUSFBKPI-UHFFFAOYSA-N Y InChI=1/C9H12N2O3/c1-2-5-14-9-4-3-7(11(12)13)6-8(9)10/h3-4,6H,2,5,10H2,1H3 Key: RXQCEGOUSFBKPI-UHFFFAOYAU
SMILES [O-][N+](=O)c1ccc(OCCC)c(c1)N
Properties
Chemical formula	C9H12N2O3
Molar mass	196.21 g/mol
Melting point	48 °C (118 °F; 321 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

In the US, food containing any added or detectable level of 5-nitro-2-propoxyaniline is deemed to be adulterated in violation of the act based upon an order published in the Federal Register of January 19, 1950 (15 FR 321).^[2]