CHEM 30B
Dr. R. Rinehart
Chapter
18: Lipids
Here’s a major hunk of fat to chew on! Hope you can digest it!!!
Fatty
Acids
common
name
shorthand
notations
#of C : # of
C=C
#of C, location of C=C
line
structure
comments
butyric acid
4:0
in butterfat
lauric acid
12:0
in coconut oil
myristic acid
14:0
in nutmeg oil
palmitic acid
16:0
in palm oil
palmitoleic acid
16:1
C16D9
in oils and fats
stearic acid
18:0
beef tallow and human fat
oleic acid
18:1
C18D9
olive oil, lard, and human fat
linoleic acid
18:2
C18D9,12
in many vegetable oils and linseed oil
a-linolenic acid
18:3
C18D9,12,15
the g- isomer D6,9,12 is not as essential
arachidonic acid
20:4
C20D5,8,11,14
precursor to prostaglandins, prostacyclins, and thromboxanes
eicosapentaenoic
acid [EPA]
20:5
C20D5,8,11,14,17
try drawing it! all the C=C are cis
an (w-3) fatty acid
docosahexaenoic
acid [DHA]
22:6
C22D4,7,10,13,16,19
try drawing it! all the C=C are cis
an (w-3) fatty acid
Waxes
beeswax
is actually a mixture of fatty esters and hydrocarbons. see below for a
typical component, where the acid and the alcohol both have 26 carbons;
the length of the fatty acid can range from 18? to 36 C and the alcohol
from 24 to 36 C
a most
useful material!
[to us as well as
to them]
Glycerolipids
class
general
structure
comments
if solid, it’s called a fat; if liquid, an oil. Melting point depends on chain length and degree of unsaturation.
diglyceride
formed during fat digestion and used as food additive [emulsifier]
monoglyceride
formed during fat digestion and used as food additive [emulsifier]
building
block of glycerophospholipids
lecithin
phosphatidyl choline
a key cell membrane component
cephalin
phosphatidyl ethanolamine
another common cell membrane component
cephalin
phosphatidyl serine
another common cell membrane component
phosphatidyl inositol
a less-common membrane component
Sphingolipids
sphingosine
the basic building block of sphingolipids, ~ never found free
ceramide
N-acyl sphingosine
the usual form from which sphingolipids are assembled
sphingomyelin
the only phosphorus-containing class of sphingolipids
cerebroside
sugar is usually gal, can be glc
ganglioside
I’m not even going to try to fit it here!
variable branched oligosaccharides
Steroids
sterane
cholesterol
sodium taurocholate
a “bile salt” sysnthesized in the liver from cholesterol and used to emulsify fat during digestion.
cortisol
elevates blood glucose levels, promotes breakdown of muscle protein and subsequent catabolism of amino acids; antiinflammatory, suppresses immune system activity.
cortisone
semisynthetic antiinflammatory agent
prednisolone
a synthetic antiinflammatory steroid
aldosterone
the main mineralocorticoid; promotes sodium reabsorption and potassium excretion in the kidneys
testosterone
the major androgen; increases muscle mass and induces male secondary sexual characteristics
androstenedione
alleged to be a human pheromone, it’s also the stuff Mark McGwire used [baseball’s drug policies are a lot laxer than those of other sports]
Dianabol
the most
popular synthetic anabolic steroid; widely abused, produces “roid
rage”
has been said to cause liver cancer
b-estradiol
the major estrogen; prevents osteoporosis and may help protect against cardiovascular conditions.
diethylstilbestrol
synthetic compound with estrogen activity; caused cervical cancer in the daughters of women who took it as a fertility agent in the ‘50s and ‘60s; used to fatten beef cattle.
progesterone
the main progestin; prepares uterine lining for implantation
Eicosanoids:
Prostaglandins, Prostacyclins, Thromboxanes,
Leukotrienes
arachidonic acid
the precursor to the 1- and 2- series; EPA is the precursor to the 3- series
PGE2
has tissue-specific effects on smooth muscle
PGF2a
has tissue-specific effects on smooth muscle; E and F types usually mutually antagonistic
PGI2
prostacyclin
prostacyclins are produced by cells in the linings of blood vessels and antagonize thromboxane activity
TXA2
thromboxane
thromboxanes are produced by activated blood platelets and activate other platelets
LTA4
leukotriene A4
LTB4
leukotriene B4
LTC4
leukotriene C4, a.k.a. SRS-A
the “slow-reacting substance of anaphylaxis”
© Ronald W. Rinehart, 2002
Structures drawn with CS ChemDraw® , MDL IsisDraw®,
and ACD Labs ChemSketch®
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