125095-12-7Relevant articles and documents
A new synthesis of α-arbutin via Lewis acid catalyzed selective glycosylation of tetra-O-benzyl-α-d-glucopyranosyl trichloroacetimidate with hydroquinone
Wang, Zhao-Xia,Shi, Xiao-Xin,Chen, Guo-Rong,Ren, Zhi-Hua,Luo, Lei,Yan, Jing
, p. 1945 - 1947 (2006)
α-Arbutin has huge application potentials in the cosmetic industry, as its inhibitory effect on human tyrosinase is stronger than that of its naturally occurring anomer arbutin (4-hydroxyphenyl β-d-glucopyranoside). Enzymatic synthesis was preferred for α-arbutin previously, and now a new chemical synthesis is reported. The reaction of tetra-O-benzyl-α-d-glucopyranosyl trichloroacetimidate, as glycosyl donor, with hydroquinone was initiated by catalytic amounts of trimethylsilyl trifluoromethanesulfonate (TMSOTf), resulting in 4-hydroxyphenyl 2,3,4,6-tetra-O-benzyl-α-d-glucopyranoside with high stereoselectivity and yield, and then to α-arbutin quantitatively after deprotection.
Syntheses of arbutin-α-glycosides and a comparison of their inhibitory effects with those of α-arbutin and arbutin on human tyrosinase
Sugimoto, Kazuhisa,Nishimura, Takahisa,Nomura, Koji,Sugimoto, Kenji,Kuriki, Takashi
, p. 798 - 801 (2003)
The effects of 4-hydroxyphenyl α-glucopyranoside (α-arbutin) and 4-hydroxyphenyl β-glucopyranoside (arbutin) on the activity of tyrosinase from human malignant melanoma cells were examined. The inhibitory effect of α-arbutin on human tyrosinase was stronger than that of arbutin. The Ki value for α-arbutin was calculated to be 1/20 that for arbutin. We then synthesized arbutin- α-glycosides by the transglycosylation reaction of cyclomaltodextrin glucanotransferase using arbutin and starch, respectively, as acceptor and donor molecules. The structural analyses using 13C- and 1H-NMR proved that the transglycosylated products were 4-hydroxyphenyl β-maltoside (β-Ab-α-G1) and 4-hydroxyphenyl β-maltotrioside (β-Ab-α-G2). These arbutin-α-glycosides exhibited competitive type inhibition on human tyrosinase, and their Ki values were calculated to be 0.7mM and 0.9mM, respectively. These arbutin-α-glycosides posessed stronger inhibitory activity than arbutin, but less activity than α-arbutin. These results suggested that the α-glucosidic linkage of hydroquinone-glycosides plays an important role in the inhibitory effect on human tyrosinase.
A method of preparing α-arbutine
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Paragraph 0030-0031, (2017/06/29)
The invention provides a method for preparing alpha-arbutin. A glycosyl donor 2,3,4,6-tetra-O-trimethylsilyl-1-iodo-alpha-D-glucose, hydroquinone and its derivative undergo a glycosylation reaction, and protection groups are removed under acidic or alkaline conditions to obtain pure alpha-arbutin. Compared with present methods for preparing alpha-arbutin, the method has the advantages of realization of the synthesis of alpha-arbutin through a one-pot process, and high selectivity and high yield obtaining of alpha-arbutin under simple and mild conditions.
Biphasic catalysis with disaccharide phosphorylases: Chemoenzymatic synthesis of α- D -glucosides using sucrose phosphorylase
De Winter, Karel,Desmet, Tom,Devlamynck, Tim,Van Renterghem, Lisa,Verhaeghe, Tom,Pelantova, Helena,Kren, Vladimir,Soetaert, Wim
, p. 781 - 787 (2014/07/08)
Thanks to its broad acceptor specificity, sucrose phosphorylase (SP) has been exploited for the transfer of glucose to a wide variety of acceptor molecules. Unfortunately, the low affinity (Km > 1 M) of SP towards these acceptors typically urges the addition of cosolvents, which often either fail to dissolve sufficient substrate or progressively give rise to enzyme inhibition and denaturation. In this work, a buffer/ethyl acetate ratio of 5:3 was identified to be the optimal solvent system, allowing the use of SP in biphasic systems. Careful optimization of the reaction conditions enabled the synthesis of a range of α-d-glucosides, such as cinnamyl α-d-glucopyranoside, geranyl α-d-glucopyranoside, 2-O-α-d-glucopyranosyl pyrogallol, and series of alkyl gallyl 4-O-α-d-glucopyranosides. The usefulness of biphasic catalysis was further illustrated by comparing the glucosylation of pyrogallol in a cosolvent and biphasic reaction system. The acceptor yield for the former reached only 17.4%, whereas roughly 60% of the initial pyrogallol was converted when using biphasic catalysis.
