3. On the DIPEPTIDE, label the following: Two central carbons, N-term, C-term, two Rgroups A dipeptide H- -C-N H OH H H CH3 Glycine Alanine

Which of the following organic compound doesnot dissolve in water? glycerol propane propanoic acid propanol H H-C Н Н H-с-с-с Н- OH HICIH H-C c-c 1 Н OH H -+ Н HICIH H Н H H C C H H OH 5-о-т OH -C-H -H OH

Name the nitrogenous bases that are bonded

1. (a) The diagram below shows a structure of monosaccharide. CH,OH C=0 H-C-OH НО—С—Н ČH,OH i. Draw the figure above on your answer sheet and indicate ALL chiral carbon(s) in your figure with *. ii. With reference to the number of carbon, the type of carbonyl group and D/L configuration, suggest a name consisting these three properties to describe the monosaccharide shown above. Explain why this monosaccharide is in D- or L- configuration as you suggested in (ii). 111. (b) The diagram below shows different configurations of glucose. CH,OH CHO ÇH,OH H H-C-OH O. OH H. H. OH H. H OH HO-C-H но H-C-OH но H. H-C-OH OH OH ČH,OH A В C i. Which glucose molecule, A or C, is in a configuration? Explain. ii. What is the name of the conversion among different configurations? iii. Glycosaminoglycans (GAG) consist of modified sugars. Give a name of the typical modification to the sugar. What makes GAG ideal for the fluid in the joints? to

how do we name the bond between monomer B and monomer C？（anomeric designation‘s name plesse）

why do so many pharmaceutical drugs contain nitrogen? How would an NH2 group benefit this dimer rather than the OH groups?

Which one bracketed region most likely illustrates a phosphodiester bond in Figure 1? The bracketed region marked ‘i’, from phosphate group to phosphate group. The bracketed region marked ‘j’, from methyl group to methyl group. The bracketed region marked ‘k’, from 3’ carbon to 5’ carbon. None of the above and I have explained my reasoning here.

Consider the structure shown below. он 3 5 CH; O CH, O H CH; O 1 H-N-CH,-C-N-CH;-C-N-CH-C-N-CH-C-N-CH-C-ơ 2 H. H H Fill in the blank with an integer (1, 2, 3, 4, 5..) as shown in the diagram or to represent a specified number. A hydrophilic side chain is indicated by the number

Circle the chiral carbons in the following compounds:

13. The structures of sphingosine and choline are given below. Draw the condensed structure and block diagram of the sphingolipid formed from these molecules and a molecule of myristic acid. CH3-(CH2)12-CH=CH-CH-OH CH₂ CH3-N-CH2-CH2-OH CH-NH2 sphingosine CH2-OH CH3 choline BLOCK DIAGRAM (draw below) CONDENSED STRUCTURE 14. Which fatty acid below should have the highest melting point? Why? Explain your answer based on structure and forces of attraction. OH O OH TOH OH