| 摘要 |
<p>Cpds. of formula (I): (where R1 is 1-3C alkyl; R2 is O, R3 is H or =6 acyl; R4 is H or =4 opt. unsatd. alkyl; R5 and R6 are H, OH or acyloxy; R7 is H, lower alkyl or acyl) are prepd. by treating a cpd. of formula (II): with base in a high b.pt. polar solvent in the presence of O2 at 70-150 degrees C, and opt. esterifying or etherifying free OH gps. Cpds. (I), some of which are novel, are medicaments or inters. thereof.</p> |
