P-Phenetidine

p-Phenetidine (4-ethoxyaniline) is a chemical compound with the molecular formula C₈H₁₁NO. It is one of the three isomers of phenetidine. It is used as an intermediate in the synthesis of pharmaceutical drugs, dyes, and the sweetener dulcin.^[1]

p-Phenetidine

Names
Preferred IUPAC name 4-Ethoxyaniline
Other names para-Phenetidine; 4-Aminophenetole
Identifiers
CAS Number	156-43-4
3D model (JSmol)	Interactive image
ECHA InfoCard	100.005.324
EC Number	205-855-5
PubChem CID	9076
RTECS number	SI6465500
UNII	9TSL224ZSE
CompTox Dashboard (EPA)	DTXSID0025864
InChI InChI=1S/C8H11NO/c1-2-10-8-5-3-7(9)4-6-8/h3-6H,2,9H2,1H3 Key: IMPPGHMHELILKG-UHFFFAOYSA-N
SMILES CCOC1=CC=C(C=C1)N
Properties
Chemical formula	C8H11NO
Molar mass	137.182 g·mol−1
Appearance	Colorless liquid; turns red to brown on exposure to air[1]
Density	1.07 g/mL[2]
Melting point	3 °C (37 °F; 276 K)[2]
Boiling point	254 °C (489 °F; 527 K)[2]
Solubility in water	20 g/L (20 °C)[2]
Hazards
Flash point	116 °C (241 °F; 389 K)[2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

p-Phenetidine is a metabolite of the pharmaceutical drugs bucetin and phenacetin^[3] and of the preservative ethoxyquin.^[4] It is also used as a chemical intermediate in the manufacture of bucetin, phenacetin, ethoxyquin, and phenacaine.

p-Phenetidine has high renal toxicity^[3] and it is believed to be responsible for the adverse effects that led to the withdrawal of phenacetin and bucetin from pharmaceutical use. p-Phenetidine is also a possible mutagen.^[4]

References

1. Merck Index (12th ed.). p. 1244. 7373. p-Phenetidine.
2. Record in the GESTIS Substance Database of the Institute for Occupational Safety and Health
3. Kankuri, Esko; Solatunturi, Erkka; Vapaatalo, Heikki (2003). "Effects of phenacetin and its metabolite p-phenetidine on COX-1 and COX-2 activities and expression in vitro". Thrombosis Research. 110 (5–6): 299–303. doi:10.1016/S0049-3848(03)00416-X. PMID 14592552.
4. "Ethoxyquin: EFSA safety assessment inconclusive". European Food Safety Authority. 2015-11-18.