Vitamin-A-s?ure Chemische Eigenschaften,Einsatz,Produktion Methoden
R-S?tze Betriebsanweisung:
R22:Gesundheitssch?dlich beim Verschlucken.
R63:Kann das Kind im Mutterleib m?glicherweise sch?digen.
R38:Reizt die Haut.
R20/21/22:Gesundheitssch?dlich beim Einatmen,Verschlucken und Berührung mit der Haut.
S-S?tze Betriebsanweisung:
S53:Exposition vermeiden - vor Gebrauch besondere Anweisungen einholen.
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S36/37/39:Bei der Arbeit geeignete Schutzkleidung,Schutzhandschuhe und Schutzbrille/Gesichtsschutz tragen.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn m?glich, dieses Etikett vorzeigen).
S36/37:Bei der Arbeit geeignete Schutzhandschuhe und Schutzkleidung tragen.
Beschreibung
all-
trans Retinoic acid is a metabolite of vitamin A and a ligand for retinoic acid receptors (RARs) with IC
50 values of 9, 3, and 10 nM for RARα, RARβ, and RARγ, respectively, in radioligand binding assays. It induces expression of a luciferase reporter in COS-7 cells expressing RARα, RARβ, or RARγ (EC
50s = 169, 9, and 2 nM, respectively). all-
trans Retinoic acid (17 nmol) reduces papilloma formation induced by phorbol 12-myristate 13-acetate (TPA; ) in mice. It reduces bile duct proliferation, hydroxyproline levels, and liver inflammation in a rat model of α-naphthylisothiocyanate-induced chronic cholestasis and reduces plasma levels of alkaline phosphatase and bile salts in the
Mdr2-/- mouse model of cholestasis. all-
trans Retinoic acid also reduces hepatic fat accumulation, triglycerides, body weight, and serum glucose levels in mice with Western diet-induced obesity.
Chemische Eigenschaften
Yellow-Orange Powder
Verwenden
Physiological metabolite of vitamin A. Effects gene expression via nuclear retinoic acid receptors (RAR); mediates cellular growth and differentiation
Indications
Topical tretinoin (Retin-A, Renova, Avita), like isotretinoin,
alters keratinization in the acroinfundibulum.
In addition, it reverses certain premalignant and other
histological changes associated with the photoaging
changes that accompany chronic exposure to ultraviolet
radiation. Topically applied tretinoin is indicated in
comedogenic and papulopustular acne vulgaris, and its
mild exfoliative effects make it sometimes useful in molluscum
contagiosum, flat warts, and some ichthyotic disorders.
It is often prescribed to lessen the clinical signs of
photoaging (wrinkling and hyperpigmented macules).
Definition
ChEBI: Retinoic acid is a retinoid in which all four exocyclic double bonds have E- (trans-) geometry. It is a naturally occurring derivative of vitamin A (retinol). Retinoids such as tretinoin are important regulators of cell reproduction, proliferation, and differentiation and are used to treat acne and photodamaged skin and to manage keratinization disorders such as ichthyosis and keratosis follicularis.
Weltgesundheitsorganisation (WHO)
Tretinoin, a retinol derivative, was introduced in 1973 exclusively
for the topical treatment of severe acne. Preparations of tretinoin are indicated for
topical use only since oral administration has been associated with risk of toxicity
from hypervitaminosis-A and subsequently of teratogenicity.
Allgemeine Beschreibung
Yellow to light-orange crystalline powder.
Air & Water Reaktionen
Tretinoin may be sensitive to prolonged exposure to air. Insoluble in water.
Reaktivit?t anzeigen
Tretinoin may discolor on exposure to light. Tretinoin is extremely sensitive to exposure to light and, therefore, Tretinoin should be fully protected from light during all handling. Solutions are unstable in the presence of strong oxidizers. Tretinoin is incompatible with strong oxidizing agents. .
Brandgefahr
Flash point data for Tretinoin are not available; however, Tretinoin is probably combustible.
Biologische Aktivit?t
Endogenous agonist for retinoic acid receptors. Also positively modulates PPAR δ receptors (K d = 17 nM). Promotes differentiation of embryonic stem cells (ESCs) into adipocytes, neurons and glia in vitro .
Clinical Use
The major toxic effect of tretinoin is erythema and
irritation of the skin to which it is applied, especially if
the skin is moist.This toxicity often decreases with continued
therapy.
Sicherheitsprofil
Poison by ingestion,
intraperitoneal, subcutaneous, and
intravenous routes. Experimental
reproductive effects. Questionable
carcinogen with experimental neoplastigenic
and teratogenic data. Human mutation data
reported. A human skin irritant. When
heated to decomposition it emits acrid
smoke and irritating fumes. Used to treat
acne and other skin problems.
l?uterung methode
Purify the acid by chromatography on silicic acid columns, and eluting it with a small amount of EtOH in hexane. Also dissolve it in Et2O, wash it with H2O, dry (Na2SO4), evaporate and the solid residue is recrystallised from MeOH (0.53g /3.5mL MeOH to give 0.14g) or EtOH. It also recrystallises from i-PrOH, or as the methyl ester from MeOH. UV in MeOH has max at 351nm ( 45,000). 9-Cis-acid forms yellow needles from EtOH, with m 189-190o, and its UV in MeOH has max at 343nm ( 36,500); the 13-cis-acid forms red-orange plates from i-PrOH with m 174-175o, and UV has max at 345nm ( 39,800). Store it in the dark, in an inert atmosphere, at 0o [Robeson et al. J Am Chem Soc 77 4111 1955]. [Beilstein 9 IV 2387.]
Vitamin-A-s?ure Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
