Betamethasone

CAS Registry No. 378-44-9,987-24-6 (acetate), 22298-29-9 (benzoate), 5593-20-4 (dipropionate), 151-73-5 (sodium phosphate), 2152-44-5 (17-valerate), 

Sample preparation 1 mL Serum -I- 100 (xL water containing 5 p.g/mL 2,3-diaminona-phthalene and 3.5 p,g/mL 18-hydro 0 -ll-deo3grcorticosterone -h 1 mL 250 mM NaOH -i- 7 mL diethyl ether, shake on a rotary shaker for 15 min, repeat extraction. Combine the organic layers and evaporate them to dryness under a stream of nitrogen at 30-40°, reconstitute the residue in 70 p-L MeOH 100 mM perchloric acid 50 50, iiyect a 20 pL aliquot. 

Mobile phase Gradient. A was 58 mM NaH2P04 containing 6 mM sodium heptanesulfon-ate, adjusted to pH 3.1 with concentrated phosphoric acid. B was MeCN MeOH 85 15. 

Extracted chloroquine, corticosterone, cortisone, dexamethasone, duocinolone acetonide, fluendrenolide, fluorometholone, fluprednisolone, hydrocortisone, hydroxychloroquine, 178-hydroxyprogesterone, meprednisone, methylprednisolone, methylprednisolone acetate, paramethasone, prednisolone, prednisone, progesterone, triamcinolone 

Noninterfering aspirin, ibuprofen, indomethacin, phenylbutazone, pregnenolone 

Chemical Name 9-fluoro-11/3,17,21-trihydroxy-16/3-methylpregna-1,4-diene-3,20-dione Common Name — 

Trade Name Menufecturer Country Year Introduced 

Betamethasone acetate is converted to betamethasone by means of hydrochloric acid in a methanol-chloroform-water mixture as described in U.S. Patent 3,164,618. 

Trade Name Manufacturer Country Year Introduced 

Mobile phase Gradient. A was 58 mM NaH2P04 containing 6 mM sodium heptanesulfon-ate, adjusted to pH 3.1 with concentrated phosphoric acid. B was MeCN MeOH 85 15. A.B from 100 0 to 78 22 over 5 min, to 70 30 over 12 min, maintain at 70 30 for 4 min, to 65 35 over 9 min. 

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Hecogenin has been used as starting material for the preparation of betamethasone (78) this genin is found in the sisal plant, sisalana. The... 

The natural compounds cortisol [50-23-7], cortisone [53-06-5], and corticosterone [50-22-6] vary only slightly in stmctures and pharmacologic properties (see Steroids). The synthetic analogues inmore modem practice, prednisolone [52438-85-4], dexamethasone [50-02-2], triamcinolone [124-94-7], and betamethasone have greater antiinflammatory potency, and their effects on sodium retention tend to be less severe. 

Betamethasone (9a-fluoro-l 1, 17a,21-trihydroxy-16 -methylpregna-l,4-diene-3,20-dione)... 

A mixture of 50 g of betamethasone, 50 cc of dimethylformamide, 50 cc of methyl orthobenzoate and 1.5 g of p-toluenesulfonicacid Is heated for 24 hours on oil bath at 105°C while a slow stream of nitrogen is passed through the mixture and the methanol produced as a byproduct of the reaction is distilled off. After addition of 2 cc of pyridine to neutralize the acid catalyst the solvent and the excess of methyl orthobenzoate are almost completely eliminated under vacuum at moderate temperature. The residue Is chromatographed on a column of 1,500 g of neutral aluminum oxide. By elution with ether-petroleum ether 30 g of a crystalline mixture are obtained consisting of the epimeric mixture of 170 ,21 -methyl orthobenzoates. This mixture is dissolved without further purification, in 600 cc of methanol and 240 cc of methanol and 240 cc of aqueous 2 N oxalic acid are added to the solution. The reaction mixture is heated at 40°-50°C on water bath, then concentrated under vacuum. The residue, crystallized from acetone-ether, gives betamethasone 17-benzoate, MP 225°-231°C. 

Bethmethasone 17-propionate (812 mg) in pyridine (10 ml) was treated with propionyl chloride (0.21 ml) at 0°C for 1 hour. Dilution with water and acidification with dilute hydrochloric acid gave the crude diester. Recrystallization from acetone-petroleum ether afforded betamethasone 17,21-dipropionate (649 mg),MP 117°C (decomposition). 

Betamethasone-21 -methanesu donate Lithium chloride Propionic anhydride... 

A solution of betamethasone 21-methanesulfonate (4 g) in dimethylformamide (25 ml) was treated with lithium chloride (4 g) and the mixture heated on the steam bath for 30 minutes. Dilution with water gave the crude product which was recrystallized to afford the title compound, MP 226°C. 

Pheniramine maleate Betaine hydrate Chloral betaine Beta -ionol Tretinoin Betamethasone... 

Betamethasone benzoate Betamethasone valerate Betamethasone acetate Betamethasone... 

Bromo pyruvaldoxime Methotrexate N-Bromosuccinimide Betamethasone acetate Bromocriptine Medrogestone 2-Bromothiophene Thihexinol... 

Betamethasone dipropionate 6-FIuoro-2-methyl tetrahydroquinoline Flumequine... 

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