Stereoselective synthesis of glycosides (glucosides, galactosides, mannosides, and xylosides) is reported using long-chain alcohols with 0-4 ethoxy spacers as potential anchored cryoprotectors.Glycolipids are one of the basic constituents of biological membranes besides phospholipids. The sugar residues in these membranes on the cell surface are playing an important role in the biological response. With this goal we have tried to analyze the influence of different sugar units on the physicochemical properties of phospholipid systems, especially hydration"] and the behavior of lipid systems during water removal under freezing condition and desiccation (lyophilization)[21 and also on the interaction between phospholipidglycolipid systems with cells131. Glycosides of long- R'OR chain alcohols are of our special interest because of the homogeneity of their mixture with phosphatidyl choline to an unlimited extent, also resulting to the formation of lipid vesicles in these mixturesr41. For these investigations we required some glycosides of different sugars with long-chain alkyl groups and with spacers containing a different number of ethyleneoxy groups between sugar and alkyl moiety.Although a number of methods [5] are known in the literature for glycosidation, none of the three existing main methods, namely the Koenigs-Knorr method, the Lewis acidcatalyzed process and the synthesis using a phase-transfer catalyst (PTC) provides good stereoselectivity in good overall yield, particularly with long-chain alcohols because of their low reactivity. Especially cis glycosidation is still prob-

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In Zusammenhang mit der kryoprotektiven Wirkung von Zuckern und Alkylglykosiden wurden entspr. Lyophilisate mit Dipalmitoylglycerophosphocholin (DPPC) IR‐spektroskopisch untersucht. An Hand der asymmetrischen Phosphatstreckbande konnte gezeigt werden, daß die untersuchten Zucker bzw. Alkylglykoside Wasserstoffbrücken mit dem DPPC ausbilden. Das Ausmaß der Verschiebung der Bande unterscheidet sich aber von der Hydratation. Der Wert der Bandenverschiebung war bei allen Zuckern einheitlich und erklärt somit nicht die unterschiedliche kryoprotektive Wirkung der Zucker.

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