The known D-threo hex-2-enopyranoside 1a is converted into an N-methyl allyl amine, the methyl urethane of which undergoes electrophile-induced cyclisation to give the iodocyclic urethane 9. The cis relationship of H3 and H4 in the latter is confirmed by NMR spectroscopy. Reduction at C2 and C6 is done simultaneously and the cyclic urethane is hydrolysed. The amino group is then acetylated and the
将已知的D-苏式hex-2-enopyranoside 1a转化为
N-甲基烯丙基胺,对其
甲基氨基甲酸酯进行亲电诱导的环化反应,得到
碘代
氨基甲酸乙酯9。证实了后者中H3和H4的顺式关系通过NMR光谱。同时在C2和C6处还原,然后将环状
氨基甲酸酯
水解。然后
氨基被乙酰化而羟基被甲基化。