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Are there any easy, not enzymatic, ways to hydrolyse $\beta$-1,2 glycosidic bonds like they occur in steviosids?

I thought of something like vinegar, which is commonly used to cleave the $\alpha$-1,2 glycosidic bond of saccharose when producing inverted sugar $-$ could that also work for the $\beta$-type?

Thank you in advance.

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  • $\begingroup$ By easy do you mean involving less energy, or less work to do? Or any other thing? $\endgroup$ – Pritt says Reinstate Monica Apr 21 '17 at 8:03
  • $\begingroup$ I mean less work to do, so one could do it at home. $\endgroup$ – AstronAUT Apr 21 '17 at 11:36
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There are non-enzymatic methods for removing the three glucose moieties of stevioside 1. Unfortunately, dilute mineral acid hydrolysis not only removes the glucose entities but also effects Wagner-Meerwein rearrangement of the aglycone steviol 2 to isosteviol 3.1 While vinegar (5% aqueous acetic acid) is a weaker acid than hydrochloric acid, I am certain that it would have been tried to avoid the rearrangement of steviol 2. Exposure of stevioside 1 with aqueous KOH effects saponification of the ester group leading to steviobioside 4.---continued---

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A more fruitful procedure that avoids rearrangement involves periodic acid cleavage of the five vicinal diols of the glucose units (marked in red in structure 1 below).2 This procedure liberates hexa-aldehyde 5 in addition to two equivalents of formic acid.3 Vigorous base treatment is required to saponify the hindered ester while base also liberates tetra-aldehyde entity by β-elimination forming steviol 2 in 75% yield. And NO, you can't do this at home.

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1) Avent, a. G., Hanson, J. R., de Oliveira, Bras H., Phytochemistry, 1990, 29, 2712.
2) Ogawa, T., Nozaki, M., Matsui, M., Tetrahedron, 1980, 36, 2641.
3) On periodic acid cleavage of vicinal diols, see: Periodic cleavage of carbohydrates

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