2,6(1,5)-Dibromo-2,6(1,5)-dideoxyhexitols were prepared by reduction of the corresponding 2,6-dibromo-2,6-dideoxyaldono-1,4-lactones with sodium borohydride. Ring closure of the dibromohexitols with aqueous ammonia gave 1,4-dideoxy-1,4-iminohexitols. The reactions were shown to proceed via epoxides. Thus, 1,4-dideoxy-1,4-imino-L-galactitol (3), the corresponding D-isomer 6, and 1,4-dideoxy-1,4-imino-D-iditol (9) and the L-iditol 12 were prepared as the crystalline hydrochlorides.
用
硼氢化钠还原相应的 2,6-二
溴-2,6-二脱氧丙二酮-1,4-内酯,制备出 2,6(1,5)-二
溴-2,6(1,5)-二脱氧己糖醇。用
氨水将二
溴己糖醇封环后得到 1,4-二脱氧-1,4-亚
氨基己糖醇。研究表明,这些反应是通过
环氧化物进行的。 因此,1,4-二脱氧-1,4-亚
氨基-L-半
乳糖醇(3)和相应的 D-异构体 6,以及 1,4-二脱氧-1,4-亚
氨基-D-iditol(9)和 L-iditol(12)都以结晶盐酸盐的形式制备出来。