Several novel pH-independent amphiphilic chlorophyll a derivatives with oligoethylene glycol substituents as

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247.918The monoterpenols borneol, verbenol, 4-(1-hydroxyethyl)carene-2, and myrtenol were glucosylated using acetobromoglucose. The structures of the prepared derivatives were established using PMR and 13 C NMR spectroscopy.Monoterpenoids are found in essential oils of many medicinal plants and medicinal agents based on them. Monoterpene glucosides have been isolated from the medicinal plants Origanum vulgare L., Rosa gallica, which possess distinct fungicidal properties [1, 2]; and Paeona peregrine, which has a unique structure and possesses adaptogenic activity among others [3,4].The physiological activity of monoterpene glucosides was studied by synthesizing glucosides of the terpene alcohols borneol (1), verbenol (2), 4-(1-hydroxyethyl)carene-2 (3), and myrtenol (4), which have chemical structures identical to the natural ones except for 3.Glucosides were synthesized using the Koenig-Knorr method [5] and silver carbonate catalyst. Unreacted monoterpenoids were removed after the reactions were completed by steam distillation. Then, compounds were purified over silica-gel columns with elution by CHCl 3 :CH 3 OH of increasing polarity.We believe that the scatter in the product yields is explained by steric hindrances in the structures of the actual monoterpenoids. In particular, the hydroxyl in 2 is more reactive because it is allylic and as far as possible from the gem-dimethyl on C-6. Therefore, the yield of verbenol glucoside is slightly greater than that of the other alcohols. The low yield of borneol (1) glucoside is explained by the fact that the C-2 hydroxyl has the endo-configuration that is known to be sterically shielded. Compounds 3 and 4 give similar yields: Compound Yeld, % 5 6 7 8 35 58 42 42