Concept explainers
Interpretation:
The structure of valine is to be stated. The rotation of valine that is prepared by halogenation of
Concept Introduction:
>The
A mixture that has equal amount of enantiomers is commonly known as racemic mixture. Enantiomers have non-superimposable mirror images of one another and therefore; they rotate the plane of polarized light in opposite but equal direction. The racemic mixture is optically inactive in nature.
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Organic Chemistry - Standalone book
- Devise a synthesis of each amino acid from acetaldehyde (CH3CHO): (a) alaninearrow_forward21.80 Prednisolone is the synthetic glucocorticoid medicine most frequently prescribed to combat autoimmune diseases. Compare its structure to the natural glucocorticoid hormone cortisone. What are the similarities and differences in structure? НО. H₂C H₂C CH₂OH C=O -ОНarrow_forwardDevise a synthesis of each amino acid from acetaldehyde (CH;CHO): (a) glycine; (b) alanine.arrow_forward
- 17) If S glutamic acid has a specific rotation of +31.5°, what is the specific rotation of R- glutamic acid? A) -15.8° B)-31.5° C) -63.0° D) +63.0° E)+31.5° 10-2-methylbutane 18) In the following reaction, F. NaSH, solvent Br A) The F is replaced by a -SH, the reaction goes via SN? and is faster in a polar aprotic so B) The Br is replaced by a -SH, the reaction goes via SN' and is faster in a polar protic sc C) The F is replaced by a -SH, the reaction goes via SN' and is faster in a polar protic sa D) The Br is replaced by a-SH, the reaction goes via SN? and is faster in a polar aprotic E) None of these is true 19) Which of the following species is the most nucleophilic? A) H2O B) F- C) HS- D) NH3 E) CH3O-arrow_forward22.1 Which of the compounds shown below has the fewest a- hydrogens? (a) H 여 (b) (c) (d)arrow_forwardC 23. a) The observed rotation for a solution containing the R and S enetaiomers a of a sample was +17.6. An enantiomerically pure sample of the S enantiomer has a specific rotation of + 22.3°. What is the % enantiomeric excess of sample A? b)A pure sample of the R-enantiomer of a compound has a specific rotation of -15°. A solution containing 0.6 g/mL of a mixture of enantiomers rotates plane polarized light by -3° in a 1 dm polarimeter. What is the enantiomeric excess (%ee) of the mixture? 9arrow_forward
- 29. What are the steps that can convert imines to amino acids? 1. LiAlH4; Water 1. NaCN; 2. Water 1. LiAlH4; 2. Ammonia O 1. NaCN; 2. Ammonia 30. Cyclohexanone reacts with NaCN to form The S-isomer The R-isomer A racemic mixture O None of the abovearrow_forwardDraw the product formed when each compound reacts with NADH (or NADPH, L Problem 13.8) in the presence of an enzyme. Each reaction occurs during the biosynthesis of an amino acid, a monosaccharide, or a lipid. do H. a. NH3 B-aspartate semialdehyde b.O,PO OPO,2- OH 1,3-bisphosphoglycerate о но C. O H. mevaldehydearrow_forwardH NH3 H₂N CO₂ Lysine CO₂ a-ketoglutarate NADPH/H* H H NH3* NADPH CO₂ Saccharopine The first step in the biological degradation of lysine is reductive amination with a-ketoglutarate to give saccharopine. Nicotinamide adenine dinucleotide phosphate (NADPH), a relative of NADH, is the reducing agent. Draw curved arrows to show the movement of electrons in this step of the reaction mechanism. Arrow-pushing Instructions H₂N H NH3+ CO₂ H-A CO₂ OH *H3N H :A CO₂ جائےarrow_forward
- ats Which of the following indicate a beta configuration at the anomeric carbon? CH,OH CH2OH OH OH OH OH OH OH OH А. В. CH2OH CH,OH OH OH OH OH OH OH OH OH D. C.arrow_forward3. How many stereogenic centres does the cholesterol have? А. 5 но В. 6 С. 7 cholesterol D. 8arrow_forwardWhat would this S2 reaction glve as a major product ? KCN ¢-CH, (28,3R) ČN ČI a) an optically Inactive racemic mixture b) an optically active single enantiomer c) two optically active diastereomers d) an optically inactive meso form e) two optically inactive diastereomersarrow_forward