| 摘要 |
<p>4-Halo-etianic acids and derivations of the formula: <CHEM> wherein X<1> is fluoro or chloro; X<2> is fluoro, chloro or hydrogen; X<3> is fluoro, chloro, bromo or hydrogen; X<4> is =C=O or <CHEM> of may be <CHEM> when X<3> is chloro; R is hydrogen, alkyl of one to six carbon atoms optionally substituted with one halo, or phenyl or benzyl optionally substituted on the phenyl ring with a substituent selected from alkyl of one to four carbon atoms, alkoxy of one to four atoms and halo; R<1> is hydrogen or alkanoyl of 2 to 6 carbon atoms; R<2> is hydrogen, alpha -methyl or beta -methyl; and the solid and broken lines between C-1 and C-2 represent a double or a single bond. The compounds wherein R is other than hydrogen are useful as anti-inflammatory agents. They can be prepared by esterifying the corresponding acid. The 17 alpha -esters can be prepared by esterifying the corresponding 17 alpha -hydroxy compounds. The 17ss-carboxylic group can be introduced by oxidising the corresponding 20-oxo-21-hydroxy (or alkanoyloxy) compound. The double bond at the 4,5 position is produced by contacting the corresponding DELTA <5> compound with a base.</p> |
