Concept explainers
Interpretation:
The structure of L-(+)-threose and L-(+)-erythrose is to be represented and the aldotriose, which must be used for the preparation of the above-mentioned compounds in the Kiliani-Fischer synthesis, is to be determined.
Concept Introduction:
▸ The Kiliani-Fischer reaction is used for increasing the number of carbon atoms of an aldose molecule, as a result of the formation of the epimeric aldonic acid.
▸ It is an effective and economic process for the synthesis of monosaccharides by the process of hydrolysis of a cyanohydrin.
▸ Furthermore, it can also be used for the production of epimers of higher aldoses from a lower aldose, that is, a single aldose produces a mixture of two diastereomeric sugars called epimers.
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Organic Chemistry
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- 4arrow_forwardWill the reduction using NaBH4 of D-glucose and D-galactose give an optically active or inactive compound?Explain why and draw your solution.arrow_forwardBelow are drawn the different chair conformations of the methyl glycoside of galactose. но он но он оМе OMe но- в A OH он (ii) Give the correct full name of compound A (= B) (ii) The name of the compound does not contain information on conformation (only configuration). Give the accepted conformational description for compound A and for compound B. (iv) Draw the Fischer projections of the open form of the corresponding reducing sugars of compound A (= B).arrow_forward
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