Chapter 29.6, Problem 10P

Maleic acid and fumaric acid are the cis- and trans- isomers, respectively, of C2H2(COOH)2, a dicarboxylic acid. Draw and label their structures.

The structural formula for the open-chain form of galactose is CH Н—ҫ—ОН Но—С—н НО—С—Н Н—ҫ—ОН CH-ОН (a) Is this molecule a sugar? (b) How many chiral carbons are present in the molecule? (C) Draw the structure of the six-member-ring form of this molecule.

The following are the pigments of spinach. Please rank them according to their polarity.  Beta-carotene Pheophytin a Pheophytin b  Chlorophyll a  Chlorophyll b  Xanthophyll

+ Mannose is a monosaccharide involved in the glycosylation of certain proteins. Several genetic disorders are associated with enzymes involved in mannose metabolism. Monosaccharides form a new functional group when the straight chain sugar cyclizes. What is the type of functional group formed in mannose after it undergoes cyclization to form the furanose ring? HO OH OH 0- OH OH A) aldehyde B) ketone C) hemi-acetal D) ether E) ester

Which of these bonds to carbon would you expect to be rela-tively reactive: C—H, C—C, C—I, C=O, C—Li? Explain

The molecule below belongs to which class of lipid? 0 CH2-0-C-(CH2)10 CH3 0 CH-O-C-(CH2)10CH 3 O i + CH2-0-P-0-(CH2)2-N(CH3)3 O glycerophospholipid O sphingolipid O triglyceride O cholesterol

5. Ribose's structure is ОН HO ОН ОН a) Draw using the arrow formalism the reaction of linear ribose to make a 5-membered ring. b) What is the name of the resulting functional group? c) Given that reaction of alcohols (such as RCH2OH) with carbonyls (such as HCO-R') to create this functional group is typically not thermodynamically favored, why does most ribose in water exist as a 5-membered ring? A few word answer is fine. d) AG°for this reaction is about - 5 kJ/mol. Assuming that you start with a 1 mM solution of ribose in water, what is the approximate concentration at equilibrium of (i) the linear form? (ii) The cyclic form? (A good answer should be correct within 20%, e.g. it is fine to approximate 9 mM as 10 mM, but it is not okay to approximate 0.1 mM as 1 mM.) e) This reaction creates a new stereocenter. Please indicate it with a *. f) Consider the starting point for synthesis of purines like ATP, which is PRPP (pheseboribosylevOrhesehate) НО НО LOLOH HO ОН HO OH Pyrophosphate…

F s fill The structure of a sphingomyelin that contains sphingosine, stearic acid, phosphate, and ethanolamine is given below. Which of the following functional groups is NOT found in this sphingomyelin? HO–CH–CH=CH–(CH2)2–CH3 HO || CH-N-C−(CH2)16—CH3 PDF UNOFFIC TRANSCR CH₂-O-P-O-CH₂-CH₂-NH3 O carboxyl group O ammonium group O hydroxyl group O carbonyl group O amide group O Search PD a pe uniz recor omiss PD

Which of the following structures is a 20:2 (Δ11,16) fatty acid? a. CH3(CH2)9CH=CH(CH2)3CH=CH(CH2)2COOHb. CH3(CH2)2CH=CH(CH2)3CH=CH(CH2)9COOHc. CH3(CH2)10CH=CH(CH2)3CH=CHCH2COOHd. CH3CH2CH=CH(CH2)3CH=CH(CH2)10COOH