Hello, I need help with the following question.

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Warner Mortensen
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Hello, I need help with the following question.

Post by Warner Mortensen »

Study the following Fischer projections to answer the questions below.
Is galactose a D-sugar or an L-sugar?
Is mannose a D-sugar or an L-sugar?
Structural isomerism and stereoisomerism are the two major kinds of isomerism. Stereoisomers with the same chemical structure but non-superimposable mirror copies of each other are known as D and L isomers. Glucose is a sugar molecule that occurs naturally as D-glucose or L-glucose. D-Glucose spins plane polarised light clockwise, whereas L-Glucose rotates plane polarised light anticlockwise. The D- and L- notation is a convenient way to designate enantiomers. For example, D-Glucose is the enantiomer of L-Glucose. The enantiomer of D-Alanine is L-Alanine.
What is Fischer Projection?
A Fischer projection, also known as a Fischer projection formula, is a two-dimensional representation of a stereo formula that preserves the stereochemical information, i.e. absolute configuration, at chiral centres. A Fischer projection is a two-dimensional representation of a three-dimensional molecule. As a result, the operations that may be done on a Fischer projection without affecting the absolute configuration at chiral centres are limited. In a Fischer projection, the operations that do not modify the absolute configuration at a chiral centre may be described as two rules.
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ChenBeier
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Re: Hello, I need help with the following question.

Post by ChenBeier »

Thanks that you to tell something from a text book.
To answer your question Galactose and also Mannose is existing in L and also in D configuration.

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https://upload.wikimedia.org/wikipedia/ ... se.svg.png
Warner Mortensen
Sr. Member
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Posts: 28
Joined: Mon Jul 26, 2021 4:13 am

Re: Hello, I need help with the following question.

Post by Warner Mortensen »

thank you
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