Crocetin-di-glucose ester

Crocus sativus L. Shi Hong Hua (Saffron) (root) Crocetin, crocetin geniobiose glucose ester, crocetin di-glucose ester, crotin, lycopene, beta-carotene.33-450 Ameliorating effect on ethanol-induced impairment of learning and memory. 

Crocetin di-glucose ester Crocetin geniobiose glucose ester... 

MeOH gradient solution (1 0 to 0 1) to yield crocetin di-glucose ester (0.41 g), crocetin gentiobiose glucose ester (5.10 g) and crocin (5.69 g). 

Crocin of 50 mg/kg ameliorated the blocking effect of ethanol on the LTP at approximately 84% compared to the control as indicated in Fig. (10). Crocetin gentiobiose glucose ester also antagonized the blocking effect of ethanol on the LTP dose-dependently. But die intensity is not so strong, about a half of crocin when compared the intensity of 50 mg/kg. On the other hand, crocetin di-glucose ester did not remove the inhibitory effect of ethanol on the LTP. 

Saffron extract contains many carotenoids such as crocetin, crocetin di-glucose ester, crocetin gentiobiose glucose ester, and crocin (crocetin di-gentiobiose ester), whose chemical structures are shown in Figure 58.1. These carotenoids scavenge free radicals, especially superoxide anions, and so may protect cells from oxidative stress. Indeed, it has been demonstrated that these carotenoids are useful in sperm cryoconservation and in protecting heptocytes from toxins. 

For the partial synthesis, a regio- and stereoselective reaction is required, in which a bond with defined stereochemistry is formed exclusively between the carboxylic acid and the carbohydrate at the anomeric carbon atom. Due to the polyene system and the ease of the hydrolysis of the ester bond at the anomeric carbon atom, the application of protecting groups on the carbohydrate is restricted. Therefore a method using unprotected carbohydrates has been developed. Crocetin-di(P-D-glucosyl) ester (543) was synthesized in 70% yield by the reaction of crocetin-diimidazolide (4) or crocetin-di(l,2,4-triazolide) (5) and unprotected p-D-glucose in pyridine in the presence of a base [5]. The esterification takes place exclusively at the anomeric carbon atom and produces only the p-anomer [6]. The method was also applied to 8 -apo-P-caroten-8 -oic acid (486) and to other carbohydrates [7]. 

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