The pyranose form of Î²-anomer of D-talose is to be drawn. The ring substituents are to be identified as axial or equatorial. Concept introduction: The pyranose form is a cyclic hemiacetal form with a six membered ring formed by the nucleophilic addition of the â€“OH group on C 5 to the C 1 carbonyl group. The furanose form is a cyclic hemiacetal form with a five membered ring formed by the nucleophilic addition of the â€“OH group on C 5 to the C 2 carbonyl group. The orientation of â€“OH group differs in Î±- and Î²- anomers. In Î±- anomer the OH on C 1 is cis to the â€“OH at the lowest chirality center in Fischer projection, while in Î²- anomer the â€“OH on C 1 is trans to the â€“OH at the lowest chirality center in Fischer projection. D sugars have the â€“O- at C adjacent to CH 2 OH on the right in the uncoiled form while L sugars have the -O- at C adjacent to CH 2 OH on the left. To draw: The pyranose form of Î²-anomer of D-talose and to identify the ring substituents as axial or equatorial.

Question

Classify the following monosaccharides as an aldose or ketose. I need help on number 5, a-d.

Answer 1

Question

Chapter 25.SE, Problem 48AP

Interpretation Introduction

Interpretation:

The pyranose form of Î²-anomer of D-talose is to be drawn. The ring substituents are to be identified as axial or equatorial.

Concept introduction:

The pyranose form is a cyclic hemiacetal form with a six membered ring formed by the nucleophilic addition of the â€“OH group on C₅ to the C₁ carbonyl group. The furanose form is a cyclic hemiacetal form with a five membered ring formed by the nucleophilic addition of the â€“OH group on C₅ to the C₂ carbonyl group.

The orientation of â€“OH group differs in Î±- and Î²- anomers. In Î±- anomer the OH on C₁ is cis to the â€“OH at the lowest chirality center in Fischer projection, while in Î²- anomer the â€“OH on C₁ is trans to the â€“OH at the lowest chirality center in Fischer projection.

D sugars have the â€“O- at C adjacent to CH₂OH on the right in the uncoiled form while L sugars have the -O- at C adjacent to CH₂OH on the left.

To draw:

The pyranose form of Î²-anomer of D-talose and to identify the ring substituents as axial or equatorial.

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Classify the following monosaccharides as an aldose or ketose. I need help on number 5, a-d.

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Fill in the empty blanks and spaces in the table. The structure of d-galactose is in the next picture for reference.