Question

(5 Marks) B. Answer the questions based on the structures given below i. ii. нонс нонс OH CH HOR OH HO CHOH CH, OH CH OH HO HOM H -OH CH, OH c. Identify the compounds ii, iii and iv as D or L. Explain how you came to this conclusion (2 marks) d. Draw the Fischer projection, enantiomer and indicate which carbons are chiral or achiral for the compound ii. (3 marks) e. Among the compounds iii and iv which is the reducing sugar? Draw the structure of the oxidized product of the reducing sugar. (2 marks) 1. For each of the disaccharide and polysaccharide give the monosaccharide units produced by hydrolysis, the type of bonds the are linked together by and the name of the disaccharide (include a or B) and polysaccharide. (4 marks) g. Explain what Mutarotation is using the structure ii. (Explain by drawing the Haworth structures of the a and B isomers.) Indicate the anomeric carbons. (3 marks)

Answer 1

Answer:

Answer Ha eco H HOH ) HO HH H JOH CH₂OH In cassbohydrate, Det notation is assigned on the basis of configuratu of last chinal centre of the chain from the top in a Fischer projection. => in , Chinal seutre eleet none gutive -OH goopis in right side so the notation is D-carbohydrate [D) - carbohydrate DH +11 CHOH CHO HO-4*2# Carobon is Chinal (13 - carbohydrate CH₂OH HOHEN НО -H H- OH CH₂OH Home is the Chinal carbon (0) - lankohydrate

dy wyr 10 *1, #₂, #3, #4 marked carsbon are Chinal carbon, 5 * are aclinal. Ho H eto HO OH OH CHOH -OH himon Ho CH₂OH Enautionens having aldehyde/ ketue gosp All monosaccharides are reducing sugan betwear ex li lux, leis is reducing sugar COOH -H ait Halt HO CH₂OH reducing ug sugan Oxidesed foromat A reducing g sugan reits

2 Muta-notation: CH2OH 10 .OH CH₂OH Н OH CH, OH HÓ HOW Н HO HO OH H 20 "OH Н OH H B. D gluease d-D -Daglucose Acc. to Lowney muuta notation is not possible without the presence of an and shiprootie Solvent that is a solvent each can functi both as an u & b like H₂o. He showed that nutarotation is abroested in pyroidine selon (basic solvent & in evesol som. Cacidie solvent), but that bé place in a mixture of pyosidine, & enesol It has been assumed that when mutanotation takes place, the ring opens then recloses in the inverted position takes on in the oraiginal position. This

due are to chain mutanotation results froom the re ready opening closing of the hemiaectal sing. The typical aldehyde reaction of D-glass reduction of tollen's & fellings reagent, form of Osazone present by small amount of open Compound, which is as fast consumed. The lone of this too bw chain stroc. is. however open easily (< 0.5%) for certain reversible like bised phite addition aldehyde reaction (8) & reaction Schiff seorganised a as it is base.

The mechanism of acid atalysed x & ß-ausmens of intero change of the Gluense is as follows. CH₂OH CH₂OH H7 HO H HO OH OH -H+ HO OH I A-D-Glucoppsansse 카 # CHLOH CHOH OH Rotation HO HO HO OH OH + ең, он CH, OH ht OH AO OH HO HO OH THI HO OH ß-B-Gluepunanese