合成路线1

The chiral dihydroxypentenal acetonide (II) is obtained from D-ribose (I) by known methods. The condensation of (II) with ethyl diazoacetate (III) by means of SnCl2 in dichloromethane gives diazocompound (IV), which is submitted to an intramolecular cyclopropanation by means of Ts-N3 and CuI in refluxing toluene to afford the bicyclo[3,1,0] hexane derivative (V). The reduction of the ketone and ester groups of (V) by means of LiAlH4 in ethyl ether provides the bicyclo diol (VI), which is deprotected with HCl in THF/water to give the chiral tetrol (VII). Selective protection of the primary OH group of (VII) with trityl chloride, TEA and DMAP in DMF yields the trityl ether (VIII), which is oxidized with NaIO4 in THF/water to afford tritylated (1S,2R)-1,2-bis(hydroxymethyl)cyclopropanemethanol (IX). The acylation of (IX) with benzoyl chloride and pyridine provides the tritylated diester (X), which is finally deprotected with formic acid in ethyl ether to furnish the target intermediate (1S,2R)-bis(benzoyloxy)cyclopropanemethanol (XI) (see intermediate (XI) in scheme no. 19209002a of the current synthesis).