| 摘要 |
<p>Cpds. of formula (I): (where R1, at posns. 6 or 7, = H, halo or lower alkoxy; A and B are either (a) both carbonyl; (b) one is hydroxy- or hydroxyimino-methylene and other is methylene in which case R2 is lower alkyl, benzyl or diphenylmethyl opt. ring substd. by halo, or (c) one is carbonyl and the other methylene in which case R2 is benzyl or diphenylmethyl opt. ring substd. by halo) and their acid salts.</p> |
