| abstract |
The present invention relates to a kind of drugs, and in particular to a kind of medical compounds and its preparation and purposes.Compound or pharmaceutically acceptable salt thereof of the present invention or its 5- hydroxyl, 4- ketone group complex compound or its solvate, structure are as follows: , wherein R1 is (CH 2 ) n, R2, R3 are selected from H or O- (CH 2 ) n-OH, R4 is selected from H or (CH 2 ) n-OH, wherein n is the integer of 1-10. |