| 摘要 |
Compounds of the formula: <IMAGE> wherein R1 is a C2-C4 alkyl; a C3-C6 cycloalkyl or benzyl; A and B are OH or A and B are OCOOR4 or B is OH and A is OCOOR4; and R4 is alkyl which are intermediates for the preparation of antitumor compounds of the formula: <IMAGE> I wherein R1 is a C2-C4 alkyl; a C3-C6 cycloalkyl; a C3-C6 cycloalkyl substituted by a halogen, hydroxy, methoxy, amino or dimethylamino group; phenyl or phenyl substituted with nitro, chlorine or methoxy thiazyl, pyridyl, pyrazyl; or a phenyl-alkyl group of the formula X-Phe-(CH2)n-, in which X is hydrogen, halogen, hydroxyl, amino, or nitro and n is an integer from 1 to 2; R2 is hydrogen, hydroxyl or acyloxy (R-COO-); where R is an alkyl having from 1 to 11 carbon atoms; and R3 is hydrogen or trifluoroacetyl and salts thereof with pharmaceutically acceptable acids. |
