Mequinol

Mequinol

Clinical data
AHFS/Drugs.com	International Drug Names
MedlinePlus	a682437
Routes of administration	Topical
ATC code	D11AX06 (WHO)
Legal status
Legal status	CA: Unscheduled US: Rx-only, Unscheduled Unscheduled
Identifiers
IUPAC name 4-Methoxyphenol
Synonyms	4-Hydroxyanisole; para-Guaiacol
CAS Number	150-76-5
PubChem (CID)	9015
IUPHAR/BPS	6827
ChemSpider	8665
UNII	6HT8U7K3AM
KEGG	D04926
ChEMBL	CHEMBL544
ECHA InfoCard	100.005.246
Chemical and physical data
Formula	C7H8O2
Molar mass	124.13722 g/mol
Density	1.55 g/cm^3
Melting point	52.5 °C (126.5 °F)
Boiling point	243 °C (469 °F)
InChI InChI=1S/C7H8O2/c1-9-7-4-2-6(8)3-5-7/h2-5,8H,1H3 Key:NWVVVBRKAWDGAB-UHFFFAOYSA-N
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Mequinol, MEHQ or 4-Methoxyphenol, is a phenol used in dermatology^[1] and organic chemistry.^[2]

Uses

Dermatology

Mequinol is a common active ingredient in topical drugs used for skin depigmentation. As a topical drug Mequinol is often mixed with tretinoin, a topical retinoid. A common formulation for this drug is an ethanolic solution of 2% Mequinol and 0.01% tretinoin by mass.^[1] Dermatologists commonly prescribe the drug to treat solar lentigines, liver spots, or age spots.

Lower dosages of mequinol have been used in conjunction with a Q-switched laser to depigment skin in patients with disseminated idiopathic vitiligo.^[3]

Organic chemistry

In organic chemistry 4-methoxyphenol is used to inhibit the radical polymerization of monomers (e.g. acrylates or styrene monomers).^[2]

Preparation

4-Methoxyphenol is produced from p-benzoquinone and methanol via a free radical reaction.^[4][5]

Safety

People can be exposed to 4-methoxyphenol in the workplace by breathing it in, skin absorption, swallowing it, skin contact, and eye contact. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 5 mg/m³ over an 8-hour workday.^[6]

See also

• Monobenzone (benzyloxyphenol)
• Hydroquinone
• Guaiacol
• 2-Hydroxy-5-methoxybenzaldehyde

References

1. Stiefel Laboratories, Inc. "Full Prescribing Information" (PDF). US Food and Drug Admistration. Retrieved 2 January 2015.
2. Hudnall, Phillip M. (2000). "Hydroquinone". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a13_499.
3. Komen, L.; Zwertbroek, L.; Burger, S.J.; van der Veen, J.P.W.; de Rie, M.A.; Wolkerstorfer, A. (2013). "Q-switched laser depigmentation in vitiligo, most effective in active disease". British Journal of Dermatology. 169 (6): 1246–1251. doi:10.1111/bjd.12571.
4. Cristian, Gambarotti; Lucio, Melone; Carlo, Punta; Suresh Udhavrao, Shisodia (2013). "Selective Monoetherification of 1,4-Hydroquinone Promoted by NaNO₂". Current Organic Chemistry. 17 (10): 1108–1113.
5. Correale, Mariano; Panseri, Pietro; Romano, Ugo; Minisci, Francesco. "Process for the preparation of mono-ethers of hydroquinones US4933504A". Google Patents. Enichem Synthesis S.P.A. Retrieved 2 January 2015.
6. "CDC - NIOSH Pocket Guide to Chemical Hazards - 4-Methoxyphenol". www.cdc.gov. Retrieved 2015-11-20.