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由二种方法合成了5-脱羟-L-来苏糖。第一法自 D-半乳糖醛酸制成其二缩乙硫醇钠盐,经脱硫成为 L-岩藻糖酸钙,再行 Ruff 降解而得5-脱羟-L-来苏糖;第二法自 L-岩藻糖合成其二缩乙硫醇,经氧化得二种二乙砜异构体(砜甲和砜乙),二者经 Fischer(H.O.L.)法降解得同一脱羟糖。由第一法所得粗糖浆借其缩乙二硫醇衍生物的制备而纯化。5-脱羟-L-来苏糖是一种粘稠的糖浆[α]_D~((?)2)=-21.6°。其苄基苯腙、缩乙二硫醇和二缩苄硫醇三乙酸酯都是很好的晶体,能用以鉴定该糖。根据紫外吸收光谱,高碘酸的消耗,以及对高锰酸钾和吡啶的反应,砜甲似为开链式不饱和的二乙砜,砜乙似属饱和的呋喃型二乙砜。从纸层析的初步结果指出末端脱羟的戊糖或己糖的比移大于相应的母糖。
Synthesis of 5-deshydroxy-L-lyxose by two methods. The first method from D-galacturonic acid made its diethyl mercaptan sodium salt, desulfurization into L-calcium fucosidate, and then Ruff degradation derived 5-deshydroxy-L-lyxose; The second method synthesizes its diethylthiol from L-fucose and oxidizes to give two kinds of diethyl sulfone isomers (sulfone A and sulfone B), which are degraded to the same dehydroxy sugar by Fischer (HOL) method. The crude syrup obtained by the first method is purified by the preparation of its ethylhexanedithiol derivative. 5-Deshydroxy-L-lyxose is a viscous syrup [α] _D ~ (?) 2) = -21.6 °. Benzylhydrazone, acetal dithiol and dibenzylthiol triacetate are all good crystals that can be used to identify the sugar. According to the UV absorption spectra, the periodic acid consumption, and the reaction with potassium permanganate and pyridine, the sulfonene group is like an open-chain unsaturated diethylsulfone, which is a saturated furan-type diethylsulfone. Preliminary results from paper chromatography indicate that the terminal dehydroxylation of pentoses or hexoses is greater than the corresponding lactose.