Monobenzon Chemische Eigenschaften,Einsatz,Produktion Methoden
R-S?tze Betriebsanweisung:
R36:Reizt die Augen.
R43:Sensibilisierung durch Hautkontakt m?glich.
S-S?tze Betriebsanweisung:
S24/25:Berührung mit den Augen und der Haut vermeiden.
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S37:Geeignete Schutzhandschuhe tragen.
Beschreibung
4-(Benzyloxy)phenol, also called monobenzone and monobenzyl ether of hydroquinone (MBEH) is an organic chemical in the phenol family with chemical formula C6H5CH2OC6H4OH. It is used as a topical drug for medical depigmentation. Monobenzone occurs as a white, almost tasteless crystalline powder, soluble in alcohol and practically insoluble in water.
The topical application of monobenzone in animals, increases the excretion of melanin from the melanocytes. The same action is thought to be responsible for the depigmenting effect of the drug in humans.
Chemische Eigenschaften
4-Benzyloxyphenol is a cream to beige-light brownish crystals classified as a hydroquinone monobenzyl ether. It is soluble in alcohol, benzene and ether, and almost insoluble in water. 4-Benzyloxyphenol is a depigmenting agent that has the effect of enhancing the rate of elimination of melanin secreted by skin cells, and studies have shown that the molecular mechanism of its action may be related to tyrosinase.
Verwenden
4-Benzyloxyphenol is used in the synthesis of bis(4-benzyloxyphenoxy)phenyl phosphine oxide. It plays an essential role in the preparation of hetaryl-azophenol dyes via heterocyclic amines in nitrosyl sulphuric acid. It is also used for polyester fiber dyeing and in rubber industry. It acts as a depigmenting agent.
Indications
Monobenzone (Benoquin) potently inhibits melanin
production and destroys melanocytes. Like hydroquinone,
monobenzone was originally introduced for
the topical treatment of disorders of excess melanin pigmentation,
including melasma. It is now used only to
permanently depigment the remaining normally pigmented
skin in patients with extensive vitiligo. Irritant
and allergic contact dermatitis are common side effects.
Definition
ChEBI: Monobenzone is the monobenzyl ether of hydroquinone. It is used as a topical drug for medical depigmentation. It has a role as a melanin synthesis inhibitor, a dermatologic drug and an allergen. It derives from a hydroquinone.
synthetische
4-Benzyloxyphenol Synthesis: Add 2.63g (0.028mol) of hydroquinone to a 100mL conical flask, weigh 1.12g (0.028mol) of sodium hydroxide, add 8mL of water, wait for the sodium hydroxide to dissolve and add dropwise to the conical flask with hydroquinone, shake well, then add 15mL of DMF and 2.52g (0.02mol) of benzyl chloride, under microwave radiation power of 320W The reaction was cooled to room temperature at the end of the reaction. The reaction was first adjusted to alkalinity with 10% sodium hydroxide, filtered, and the filtrate was washed with 10% sodium hydroxide until the filtrate was colorless (the filtrate was hydroquinone bis(benzyl ether), which could be recycled). The filtrate was acidified with hydrochloric acid to make Monobenzone completely precipitated, and then washed by filtration and ice water, recrystallized with alcohol and water, and decolorized by activated carbon to obtain 2.55g of white solid, the yield was 63.79%.
Nebenwirkungen
Side effects:
Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
Intense itching, blistering, burning, or swelling of the skin.
Mild skin rash, tenderness, or redness.
l?uterung methode
Crystallise it from EtOH or H2O, and dry (P2O5) under vacuum. [Walter et al. J Am Chem Soc 108 5210 1986, Beilstein 6 IV 5778.]
Monobenzon Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
