| 摘要 |
<p>The present invention relates to compounds of formula (I), in which formula R represents hydrogen, or R represents (C1-C6)alkyl, phenyl, or (C7-C9)aralkyl, optionally substituted with one or more groups selected from (C1-C3)alkyl, F, and phenyl; n is an integer having the value 0, 1, or 2; and X represents hydroxy or halogen.</p> |
