030 CHAPTER 26 Lipids
- Nutmeg contains a simple, fully saturated triacylglycerol with a molecular weight of 722. Draw its structure.
- Give the product that would be obtained from the reaction of cholesterol with each of the following reagents: (Hint:Because of
steric hindrance from the angular methyl groups, the is more susceptible to attack by reagents than the .)
a.
b. in THF, followed by
c. Pd C
d.
e. peroxyacetic acid
f. the product of part - Dr. Cole S. Terol synthesized the following samples of mevalonic acid and fed them to a group of lemon trees:
Which carbons in citronellal, which is isolated from lemon oil, will be labeled in trees that were fed the following?
a. sample A b. sample B c. sample C- An optically active monoterpene (compound A) with molecular formula undergoes catalytic hydrogenation to form an
optically inactive compound with molecular formula (compound B). When compound B is heated with acid, followed by
reaction with and workup under reducing conditions one of the products obtained is 4-methylcyclohexanone. Give
possible structures for compound A. - If junipers were allowed to grow in a medium containing acetate in which the methyl carbon was labeled with which carbons
in would be labeled? - a. Propose a mechanism for the following reaction:
b. To what class of terpene does the starting material belong? Mark off the isoprene units in the starting material.- 5-Androstene-3,17-dione is isomerized to 4-androstene-3,17-dione by hydroxide ion. Propose a mechanism for this reaction.
5-androstene-3,17-dioneH 3 CH 3 COHO−
H 2 OO4-androstene-3,17-dioneH 3 CH 3 COOCH 3CH 3CH 3 CH 3H 3 CH 3 CHOH+CH 3CH 3 H 3 C CH 3H 3 C CH 3CH + H^3 O+
3H 3 C CH 3CH 3a-terpineol14 C,O 3 , 1 Zn, H 2 O 2 ,C 10 H 20 OC 10 H 18 OCH 2 CO−CH 3 CCH 2 CH 2 OHOHO
sample ACH 2 CO−CH 3 CCH 2 CH 2 OHOHO
sample BCH 2 CO−CH 3 CCH 2 CH 2 OHOHO
sample C1414 14cholesterolH 3 C HH HH 3 CHOe+CH 3 O-Br 2 +H 2 OH 2 , >BH 3 H 2 O 2 +HO-H 2 O, H+a-face b-face