| 摘要 |
<p>3-Oxo-13beta-R - gona 4,9,11-trienes (I) where R = lower alkyl Y = OH, Z = H or Y and Z together represent ketonic oxygen, are prepd. from cpd. of formula (II) by dehydration, using an acid, to give a 3,5-diketo- 13beta-R-17 4,5-seco gona-9,11-diene (III), followed by cyclisation with an alkali.</p> |
