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Lipids. Lipids. Lipids are natural products more soluble in nonpolar solvents than in water. Some of them are related in that they have acetic acid (acetate) as their biosynthetic origin. Acetyl coenzyme A serves as the source of acetate. - PowerPoint PPT Presentation
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LipidsLipids
LipidsLipids
Lipids are natural products more soluble in Lipids are natural products more soluble in nonpolar solvents than in water.nonpolar solvents than in water.
Some of them are related in that they have Some of them are related in that they have acetic acid (acetate) as their biosynthetic origin.acetic acid (acetate) as their biosynthetic origin.
Acetyl coenzyme A Acetyl coenzyme A serves as the source of serves as the source of acetate.acetate.
Some of them are related in that they have Some of them are related in that they have isoprene as their biosynthetic origin.isoprene as their biosynthetic origin.
Fats, Oils, and Fatty AcidsFats, Oils, and Fatty Acids
Fats and OilsFats and Oils
Fats and oils are naturally occurring mixture of Fats and oils are naturally occurring mixture of triacylglycerols (also called triglycerides).triacylglycerols (also called triglycerides).
Fats are solids; oils are liquids.Fats are solids; oils are liquids.
RCOCHRCOCH
CHCH22OCR'OCR'OO
CHCH22OCR"OCR"
OO
OO
OO
R'CR'COCHOCH
CHCH22OOCRCROO
CHCH22OOCR"CR"
OO
Fatty AcidsFatty Acids
Acids obtained by the hydrolysis of fats and oils are called Acids obtained by the hydrolysis of fats and oils are called fatty acids. fatty acids.
Fatty acids usually have an unbranched chain with an even Fatty acids usually have an unbranched chain with an even number of carbon atoms.number of carbon atoms.
If double bonds are present, they are almost always cis.If double bonds are present, they are almost always cis.
HH22OOHOCHHOCH
CHCH22OHOH
CHCH22OHOH
OO
HOCRHOCROO
R'COHR'COH
OO
HOCR"HOCR"
Which one of the following is a triacylglycerol Which one of the following is a triacylglycerol (triglyceride), a fat?(triglyceride), a fat?
A)A) B)B)
C)C) D)D)
QuestionQuestion
QuestionQuestion
Which of the following is not an expected Which of the following is not an expected product of the acid hydrolysis of fats?product of the acid hydrolysis of fats?
A)A) CHCH33(CH(CH22))1212COCO22HH
B)B) HOCHHOCH22CHCH22(OH)CH(OH)CH22OHOH
C)C) CHCH33(CH(CH22))1616COCO22HH
D)D) CHCH33(CH(CH22))1414COCO22HH
Fatty AcidsFatty Acids
Systematic name: Systematic name: (5Z, 8Z, 11(5Z, 8Z, 11ZZ, 14, 14ZZ)-5,8,11,14-)-5,8,11,14-Icosatetraenoic acidIcosatetraenoic acid
Common name: Arachidonic acidCommon name: Arachidonic acid
HH
HH HH
HH
HH HHHH
HH
OHOH
OO
PhospholipidsPhospholipids
WaxesWaxes
WaxesWaxes
Waxes are water-repelling solids that coat the Waxes are water-repelling solids that coat the leaves of plants, etc.leaves of plants, etc.
Structurally, waxes are mixtures of esters. The Structurally, waxes are mixtures of esters. The esters are derived from fatty acids and long-esters are derived from fatty acids and long-chain alcohols.chain alcohols.
WaxesWaxes
Waxes are water-repelling solids that coat the Waxes are water-repelling solids that coat the leaves of plants, etc.leaves of plants, etc.
Structurally, waxes are mixtures of esters. The Structurally, waxes are mixtures of esters. The esters are derived from fatty acids and long-esters are derived from fatty acids and long-chain alcohols.chain alcohols.
CHCH33(CH(CH22))1414COCHCOCH22(CH(CH22))2828CHCH33
OO
Triacontyl hexadecanoate: occurs in beeswaxTriacontyl hexadecanoate: occurs in beeswax
Question Question
When cetyl palmitate is subjected to saponification conditions When cetyl palmitate is subjected to saponification conditions (NaOH, H(NaOH, H22O, heat) which two compounds will be formed? O, heat) which two compounds will be formed?
A)A) CHCH33(CH(CH22))1515OH + HOCHOH + HOCH22(CH(CH22))1414CHCH33
B)B) CHCH33(CH(CH22))1414COCO22Na + NaONa + NaO22C(CHC(CH22))1414CHCH33
C)C) CHCH33(CH(CH22))1414COCO22H + HOCHH + HOCH22(CH(CH22))1414CHCH33
D)D) CHCH33(CH(CH22))1515OH + NaOOH + NaO22C(CHC(CH22))1414CHCH33
ProstaglandinsProstaglandins
ProstaglandinsProstaglandins
Prostaglandins are involved in many biological Prostaglandins are involved in many biological processes.processes.
Are biosynthesized from linoleic acid (CAre biosynthesized from linoleic acid (C1818) via ) via arachidonic acid (Carachidonic acid (C2020). ).
O
HO
OH
COOH
Prostaglandin E2
OH
HO
OH
COOH
Prostaglandin F1
CO2
Hcyclooxygenase
Prostaglandins
aspirin inhibits enzyme
(Chimes?)
Diterpenes & PainDiterpenes & PainAspirin’s Mode of Action - Prostaglandin CascadesAspirin’s Mode of Action - Prostaglandin Cascades
Aspirin Inhibits the Synthesis of Prostaglandins
(prostaglandin endoperoxide synthase)
