Valeric 1,3,4-trihydroxy

Fluoro-llb,17a,21-trihydroxy-16b-methyl-17-[(l-oxopentyl)oxyl]-pregna-l,4-diene-3,20-dione. See b-Methasone valerate. 

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

The valerate is made from betamethasone as a starting material as follows A suspension of 9a-fluoro-1 ip,17a,21-trihydroxy-16/3-methylpregna-1,4-diene-3,20-dione (betamethasone) (2 grams) in sodium dried benzene (500 ml) was distilled vigorously for a few minutes, toluene-p- ulfonic acid monohydrate (30 mg) and methyl orthovalerate (5 ml) were added and distillation was continued for 10 minutes. The mixture was then boiled under reflux for 1.5 hours after which time unreacted betamethasone alcohol (400 mg) was removed by filtration. The benzene solution was treated with solid sodium bicarbonate and a few drops of pyridine, filtered and evaporated to dryness at about 50°C. The residue, in ether, was filtered through grade III basic alumina (20 grams) to remove traces of unreacted betamethasone alcohol, the ether removed in vacuo and the residue of crude betamethasone... 

Synonyms 9a-fluoro-16(3-methyl-ll(3,17a,21-trihydroxy-l,4-pregnadiene-3,20-dione-17-valerate 9a-fiioro-16 p-methylprednisolone- 17-valerate ... 

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