| 摘要 |
Compounds of structure (I), wherein R4, R5, R6 and R7 individually are H, OH or C1-C18 O-acyl and R3 is H, C1-C18 acyl or (1); or R5 and R7 are H or OH, R6 is H and together R3 and R4 are (2); and X is =O or =S; Y is -OH, -SH, -NH2 or halogen; and Z is H, -NH2, -OH or halogen; wherein halogen is Cl or Br; or pharmaceutically acceptable salt thereof are useful as antivirals, antitumors, antimetastatics and as immune system enhancers. |
