7α-Chlor-11β,17,21-trihydroxy-16α-methylpregna-1,4-dien-3,20-dion-17,21-di(propionat)

BeschreibungAlclometasone dipropionate (ACM) is a synthetic nonfluorinated corticosteroid which has been marketed since 1986 for the topical treatment of inflammatory and pruritic corticosteroid-responsive dermatoses. As esterification of the hydroxyl group at positions 17 and 21 of the alclometasone molecule enhances topical anti-inflammatory activity, the dipropionate salt of alclometasone is much more potent than alclometasone itself. It reduces cutaneous anaphylaxis reactions induced by tuberculin or albumin in mice when administered topically (20 μl of a 0.1% solution). ACM also inhibits androgen-dependent cytochrome P450 activity and the O-depropylation activity of 7-alkoxy-coumarin O-dealkylase in a dose-dependent manner in male rats but has no effect on hepatic drug metabolism in female rats or mice of both sexes. Formulations containing ACM have been used to treat radiation, allergic contact dermatitis and psoriasis.

VerwendenAlclometasone dipropionate is a corticosteroid used topically for its glucocorticoid activity in the treatment of various skin disorders. It is usually used as a cream or ointment containing 0.05%. It is topically used in dermatology as an anti-inflammatory, antipruritic, antiallergic, antiproliferative and vasoconstrictive agent. Alclometasone dipropionate has been used since 1986 for the treatment of corticosteroid-responsive dermatoses. It is ranked in Group 6 based on potency and has been dassified as group D. According to the A-D grouping, patch-test reactions occur six to seven times more frequently within well-defined groups of structurally related chemicals than between corticosteroids of different groups.

synthetischeAlclometasone dipropionate synthesis: The dehydrogenation of 16alpha-methyl-11beta,17alpha,21-trihydroxypregna-1,4-diene-3,20-dione-21-acetate (I) with dichlorodicyanobenzoquinone (II) in dioxane HCl gives 16alpha-methyl-11beta,17alpha,21-trihydroxypregna-1,4,6-triene-3,20-dione-21-acetate (III), which is hydrolyzed with aqueous NaHCO3 to the corresponding free triol (IV). The reaction of (IV) with triethyl orthopropionate (A) by means of p-toluenesulfonic acid in DMSO yields 16alpha-methyl-11beta,17alpha,21-trihydroxypregna-1,4,6-triene-3,20-dione-17,21-ethylorthopropionate (V), which is hydrolyzed partially with acetic acid to 16alpha-methyl-11beta,17alpha,21-trihydroxypregna-1,4,6-triene-3,20-dione-17-propionate (VI). The acylation of (VI) with propionic anhydride affords 16alpha-methyl-11beta,17alpha,21-trihydroxypregna-1,4,6-triene-3,20-dione-17,21-dipropionate (VII), which is finally treated with dry HCl in dioxane.