| 摘要 |
NEW MATERIAL:A compound expressed by formula I (R<1>-R<3> represent lower alkyl). EXAMPLE:A compound expressed by formula II. USE:A raw material for synthesis of a compound expressed by formula III useful as a caricinostatic agent. PREPARATION:For example, a compound expressed by formula IV is treated in the presence of an aluminum halide and a nucleophilic agent (example; tetrahydrothiophene, etc.), as necessary, in a halogenated hydrocarbon based solvent, normally at 0-90 deg.C. Then the obtained compound expressed by formula V is treated with 2 equivalents base (example; lithium diisopropylemide, etc.) and the produced dianion is protected by a silylating agent (example; trimethylsilyl chloride, etc.). The reaction is preferably carried out, desirably in a solvent, e.g. THF, etc., Normally at -78 deg.C - room temperature.
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