Concept explainers
(a)
Interpretation:
Whether D-erythrose and L-erythrose are enantiomers or diastereomers has to be stated.
Concept Introduction:
Enantiomers are the compounds with same chemical formula but differ in configuration of the chiral center. These are known as optical isomers. Enantiomers are basically stereo-isomers of the same compound. Two compounds are called enantiomers of each other if they are a non-superimposable mirror images of each other.
Diastereomers are also the compounds with the same chemical formula. These are also a type of stereo-isomers. Two compounds are called diastereomers of each other if both the compounds have different configuration at the one or more (not all) equivalent stereo centers. These are not mirror images of each other.
(b)
Interpretation:
Whether L-erythrose and L-threose, enantiomers or diastereomers are to be stated.
Concept Introduction:
Enantiomers are the compounds with same chemical formula but differ in configuration of the chiral center. These are known as optical isomers. Enantiomers are basically stereo-isomers of the same compound. Two compounds are called enantiomers of each other if they are a non-superimposable mirror images of each other.
Diastereomers are also the compounds with the same chemical formula. These are also a type of stereo-isomers. Two compounds are called diastereomers of each other if both the compounds have different configuration at the one or more (not all) equivalent stereo centers. These are not mirror images of each other.
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EP ESSENTIAL ORG.CHEM.-MOD.MASTERING
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- A Fischer projection of a monosaccharide is shown below: CH2OH C=O H- = 2 HO- HO -OH H H CH₂OH Classify this monosaccharide (e.g., aldotriose) Does it have the D or L configuration?arrow_forwarda. How many stereogenic centers are present in α-D-galactose? b. Label the hemiacetal carbon in α-D-galactose. c. Draw the structure of β-D-galactose. d. Draw the structure of the polyhydroxy aldehyde that cyclizes to α- and β-D-galactose.arrow_forwardConsider the following compound, which is used by insects and some fungi to store energy:arrow_forward
- 1. Which of the following is not true to the monosaccharide below? H. ОН но- -H- но ОН ĆH2OH O It is the Fischer Projection of D-glucose. It is an aldohexose having 4 chiral centers and 24 stereoisomers. It is has a D-glucose because OH- group bonded to the highest numbered chiral C is pointing to the right. It is a polyhydroxy ketone having 8 enantiomeric pair.arrow_forwardHow many stereocenters are present in D-glucose? How many stereocenters are present in D-ribose? How many stereoisomers are possible for D-glucose? How many stereoisomers are possible for D-ribose?arrow_forwardConsider only the top monosaccharide chair conformation. How would I draw the Fischer projection of the aldohexose from which this chair conformation is derived? And is the diaccharide shown reducing, non-reducing, or can that not be determined?arrow_forward
- 14․ Identify the following as an ? or ? form and draw the Haworth structure of the other anomer. 15․ Below are the Fischer projections of monosaccharides.arrow_forward(d) Draw the structure of the expected product when monosaccharide B undergo mutarotation upon dissolving in water in the presence of Tollens reagent (AGNO3, NHẠOH). он OH O. OH OH OH monosaccharide Barrow_forwardASELS A Fischer projection of a monosaccharide is shown below: CHO HO- H H- H -OH -OH CH₂OH Classify this monosaccharide (e.g., aldotriose) E Does it have the D or L configuration?arrow_forward
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