合成路线1

2) The esterification of Shikimic acid (XIV) with MeOH/TsOH gives the methyl ester (XV), which is treated with 2,2-dimethoxypropane (II) and TsOH to yield the acetonide (XVI). The mesylation of (XVI) with mesyl chloride and TEA in dichloromethane gives the mesylated acetonide (XVII), which is hydrolyzed with HCl, yielding the dihydroxy ester (XVIII). The epoxidation of (XVIII) with DBU in THF affords the epoxide (XIX), which is protected with methyl chloromethyl ether to give compound (XX). The reaction of (XX) with sodium azide in refluxing methanol/water provides the hydroxy azide (XXI), which is acylated with mesyl chloride to the mesylate (XXII). The cyclization of (XXII) by means of triphenylphosphine in THF affords the aziridine (XXIII), which is treated with sodium azide in hot DMF to give the amino azide (XXIV). The deprotection of (XXIV) with HCl followed by tritylation of the free amino group with trityl chloride and TEA yields compound (XXV), which is cyclized by means of mesyl chloride and TEA to afford the tritylaziridine (XXVI). The cleavage of the aziridine ring of (XXVI) with 3-pentanol, followed by acetylation of the resulting amino group, affords the acetamido aziridine (XXVII), which is hydrolyzed at the ester group with KOH in THF/water to give the carboxylic acid (XXVIII). The esterification of (XXVIII) with ethanol, DCC and DMAP in dichloromethane affords the azido ester (XIII), which is finally reduced with triphenylphosphine in hot THF/water.