Several dihydrochalcone glucosides have been synthesised and their potential value as possible sweetening agents have been assessed. Some of these dihydrochalcone glucosides were isolated as gums. These were the glucosides of 4'-hydroxydihydrochalcone; 4,4'-dihydroxy-dihydrochalcone; 3,4'-dihydrozy-4-methoxydihydrochalcone; 4'-hydroxy-3,4-dimethoxydihydrochalcone and 4'-hydroxy-2-methoxydihydrochalcone. Two more of these compounds were obtained as solids, however. These were: 4,4'-dihydroxydihydrochalcone as a pale yellow, waxy sol.id and 4'-hydroxy-3,4-methylenedioxydihydrochalcone as a white, crystalline solid. All these dihydrochalcone glucosides were found to be non-sweet. The dihydrochalcone aglycone 3,4'-dihydroxy-4-niethoxydihydrochal-cone produced an enhanced sweetness sensation when added to 5% w/v solutions of either glucose, sorbitol or mannitol. Naringin dihydrochalcone and Neohesperidin dihydrochalcone were prepared and their sweetness characteristics were assessed in Quosh and Chekwate Orange Drinks. These sweeteners produced a delayed sweet-ness effect, a gasp effect and their sweetnesses were of a lingering, cloying nature. In Quosh Orange Drink the sweetness equivalence of neohesperidin dihydrochalcone was found to be 3.8 X saccharin at the concentration used. The corresponding figure for naringin dihydrochal-cone was 0.19 X saccharin. In Chekwate Orange Drink the sweetness equivalences for neohesperidin and naringin dihydrochalcones were 6.4 and 0.21 X saccharin, respectively. It is suggested that the glucose and rhamnose constituents of the neohesperidose moiety in neohesperidin dihydrochalcone adopt the CI conformation as it interacts with the human taste-bud receptor. This conformation would allow two pairs of OH groups to adopt the gauchoconformation so that the inter-hydroxyl distance is ca. 3A. If the IC conformation were adopted, only one hydroxyl pair would adopt the gauche conformation with attendant diminution in sweetness intensity. Attempts to prepare dihydrochalcone disaccharides from simple starting materials were unsuccessful. The compounds investigated weret: 4-hydroxyacetophenone-4-B-neohesperidoside; 4-hydroxyacetophenone-4-B-sophoroside; 4-hydroxyacetophenone-4-B-laminaribioside and 4-hydroxy-acetophenone-4-maltoside.
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