| 摘要 |
Compounds of the formula: <IMAGE> wherein the symbols X each represent hydrogen or methoxy, R represents hydrogen or carboxymethyl, the symbols R1 each represent hydrogen or together represent a valency bond and the symbols R2 each represent hydrogen or together represent a valency bond, the pair of symbols R2 having the same significance as the pair of symbols R1, and when the symbols R1 and R2 represent hydrogen the symbol X also represents hydrogen, are new compounds possessing antiviral activity. |
