D-4-(4-Hydroxy-3,5-diiodphenoxy)-3,5-diiodbenzylalanin Chemische Eigenschaften,Einsatz,Produktion Methoden
R-Sätze Betriebsanweisung:
R20/21/22:Gesundheitsschädlich beim Einatmen,Verschlucken und Berührung mit der Haut.
R40:Verdacht auf krebserzeugende Wirkung.
S-Sätze Betriebsanweisung:
S36/37:Bei der Arbeit geeignete Schutzhandschuhe und Schutzkleidung tragen.
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
S22:Staub nicht einatmen.
Chemische Eigenschaften
beige to light grey powder
Verwenden
One of the thyroid hormones involved in the maintenance of metabolic homeostasis. Synthesized and stored as amino acid residues of thyroglobulin, the major protein component of the thyroid follicular colloid. Synthesis and secretion are regulated by the pituitary hormone (TSH). Deiodinated in peripheral tissues to the active metabolite, liothyronine. The D-form has very little activity as a thyroid hormone, but has been used to treat hyperlipidemia.
Definition
ChEBI: The D-enantiomer of thyroxine.
Biologische Funktion
Dextrothyroxine, the synthetic D-(+)-stereoisomer isomer of L-(–)-T4, was introduced in hypocholesteremichypolipidemic therapy with the premise that it would be void of calorigenic effects. The possibility of trace
contamination with and metabolic conversion to T4 and congeners has restricted its use, however,
especially in patients with coronary heart disease.
Mechanism of action
Dextrothyroxine speeds up the decomposition of cholesterol and lipoproteins, thus activating
catabolism of cholesterol in the liver, which results in cholesterol being more intensively
transformed into bile salts. It lowers the level of low-density lipoproteins in the
plasma and very low-density lipoproteins in fatty tissue. It is recommended for treating
hyperlipoproteinemia.
läuterung methode
Recrystallise D-thyroxine from H2O (needles) or from an ammonical solution by dilution with H2O, MeOH or Me2CO. It has also been purified by dissolving ~6.5 g in a mixture of MeOH (200mL) and 2N HCl (20mL), adding charcoal, filtering then adding NaOAc solution to pH 6. On standing the thyroxine separates, it is filtered off, washed with MeOH then Me2CO and dried in vacuo. N-Formyl-D-thyroxine has m 210o and [] 21 -26.9o (c 5, EtOH). (±)-Thyroxine has m 256o and is purified in the same way. [Nahm & Siedel Chem Ber 96 1 1963, Salter Biochem J 24 471 1930, Beilstein 14 I 671, 14 II 384, 14 III 1566, 14 IV 2374.]
D-4-(4-Hydroxy-3,5-diiodphenoxy)-3,5-diiodbenzylalanin Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
