Beclomethasone-17,21 dipropionate

Sample preparation 50 n.L Plasma -i- 100 jiL 20 p,g/mL cloprednol + 3 mL ether, shake 10 min, centrifuge at 3000 g, remove the organic phase and evaporate it to dryness under nitrogen. Take up the residue in 200 pL mobile phase, inject a 50 pL aliquot. 

Mobile phase MeOH MeCN water acetic acid 400 100 200 1 Ipjection volume 50 Detector UV 254 

Wurthwein, G. Rohdewald, P. Activation of beclomethasone dipropionate by hydrolysis to beclomethasone-17-monopropionate. Biopharm.Drug Dispos., 1990, 11, 381-394 

Sample preparation Acidify plasma or lung tissue homogenate to pH 2 with 500 mM HCl, add 100 pL 20 pg/mL IS, extract with 8 mL dichloromethane. Evaporate the organic layer to dryness under vacuum, reconstitute in 120 pL MeOH 5% acetic acid 50 50, inject an 80 pL aliquot. 

Chanoine, F. Grenot, C. Heidmann, R Junien, J.L. Pharmacokinetics of butixocort 21-propionate, bu-desonide, and beclomethasone dipropionate in the rat after intratracheal, intravenous, and oral treatments. Drug Metab.Dispos., 1991, 19, 546—553 

Therapeutic Function Topical anti-inflammatory glucocorticoid 

Chemical Name 9-chloro-11/3,l7,21-trihydroxy-16/3-methylpregna-1,4-diene-3,20-dione dipropionate 

Trade Name Manufacturer Country Year Introduced 

Schering Byk-Essex Script Intel Script Intel 

16j3-Methyl-1,4-pregnediene-11/3,17a,21 -triol-3,2-dione-21-ecetete 

Hydrolysis of the acetate ester with alkali, e.g., sodium methoxide in methanol, affords the free alcohol, 16/3-methyl-1,4,9(11)-pregnatriene-17a, 21-diol-3,20-dione. To a suspension of 3 grams of 16/3-methyl-1,4,9(11)-pregnatriene-17a,21-dioi-3,20-dione-21-acetate in 40 mi of acetone is added at 0°C with stirring 2 grams of N-chiorosuccinimide and then 7 mi of a per-chioric acid solution prepared by dissoiving 0.548 ml of 70% perchloric acid in 33 ml of water. The resulting reaction mixture is stirred at 0°C for about 4 hours 45 minutes. 

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Beclomethasone dipropionate Cream, lotion, ointment 0.025 Medium —... 

Beconase (beclomethasone dipropionate) 2 inhalations in each nostril, bid... 

Freiwald M, Valotis A, Kirschbaum A, McClellan M, Murdter T, Fritz P, Friedel G, Thomas M, Hogger P (2005) Monitoring the initial pulmonary absorption of two different beclomethasone dipropionate aerosols employing a human lung reperfusion model. Respir Res 24 6-21. 

Kuzuya Y, Adachi T, Hara H, Anan A, Izuhara K, Nagai H (2004) Induction of drug-metabolizing enzymes and transporters in human bronchial epithelial cells by beclomethasone dipropionate. IUBMB Life 56(6) 355-359. 

The aerosol solution does not require shaking. Two actuations of the 40 meg strength should provide a dose comparable to 1 actuation of the 80 meg strength. The recommended dosage relative to CFC-based beclomethasone dipropionate (CFC-BDP) inhalation aerosols is lower because of differences in delivery characteristics between the products. 

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