ORGANIC CHEMISTRY Chapter 10
Organic chemistry - study of carbon-containing compounds
(1) Single bond
(2) Double Bond
Double and triple bonds are referred to as "unsaturated"
(3) Triple Bond H-C/ C-H
(1) Molecular formula-number and kinds of atoms, but no idea what it looks like C4H10
(2) Structural formula - order of attachment of atoms in a molecule.
(3) Dimensional formula - geometry stressed. Important biochemically to fit in the active sites of enzymes.
Types of reactions
1. Isomerization Isomers have the same molecular formula but the atoms are arranged differently. Both glucose & fructose have the same formula C6H12O6 but they are different sugars.
2. Hydrogenation Adding hydrogen atoms to the compound. Plant oils have a lot of unsaturated fatty acids and they are liquid. To make solid shortening (solid Crisco), or solid margarine, hydrogen atoms are added across the unsaturated bonds of the plant oils. When this is done, some of the new fatty acids have a different configuration in space and are called >trans= fatty acids. These are bad for health
3. Dehydrogenation Taking away hydrogens to make a double bond or to give the hydrogens to another compound.
Hydrogenation/dehydrogenation reactions are very important in biochemistry. We make energy called ATP by these transfers.
4. Hydration Adding a water molecule
5. Dehydration Taking a water molecule out
6. Halogenation Adding chlorine, fluorine, bromine, or iodine to a compound.
7. Deamination Amines have Nitrogen. Ammonia is NH3. To deaminate a compound means to take the N containing group off. Amino acids have NH2 groups.
8. Oxygenation To add oxygen
OXIDATION AND REDUCTIONS REACTIONS ARE VERY IMPORTANT IN BIOCHEMISTRY. THIS IS THE ENERGY CYCLE.
Organic compounds have endings that tell what type of compound they are. Alkanes end in Aane@
so pentane is a 5 carbon alkane. Alcohols end in Aol@ so pentanol is 5 carbon alcohol.
Number of carbons: meth = 1 eth = 2
prop = 3 but = 4 pent = 5
hex = 6 hept =
Classes of compounds:
Alkanes are hydrocarbons having hydrogen and carbon and have the formula CnH2n+2
CH4 is methane take away 1 hydrogen -CH3 is called
What would be butyl?
What would be pentyl?
short hand representation
These two formulas are called 3-methyl pentane. Why?
Just like alkanes but with one or more double bonds.
C - C - C - C- C = C - C
The 2 tells where the double bond is.
C - C = C - C = C - C - C 2,4-heptadiene diene = 2 double bonds triene = 3 double bonds
Just like alkanes but with a triple bond. We don=t see them in biochemistry
Have OH groups. Very important in biochemistry.
C - C- OH ethanol
C - C - C-OH propanol
C- OH methanol (fill in the extra bonds with H=s)
OH groups hold water loosely. Glycerol is used to retain moisture. Hydrogen bonding with H2O
The sugars have many alcohol (OH) groups
Reactions of alcohols
1) Take out a water - dehydrase get a double bond
2) Add a water across a double bond to get an alcohol
3) Oxidize to an aldehyde
4) Oxidize to an acid
5) Oxidize to a ketone
We see these types of reactions when glucose gets oxidized to carbon dioxide and water.
Every time a compound gets oxidized, another compound gets reduced.
In the oxidation of sugars the compounds that get reduced are NAD and FAD, which go to NADH and FADH. This is tied to phosphorylation - adding a phoshpate group.
The sugars get oxidized. NAD and FAD get reduced to NADH & FADH which are in the mitochondria (the energy producing part of the cell).
ADP (adenosine diphosphate) goes to ATP (adenosine triphosphate) ATP is the energy of the cell
C6H12O6 + 6 O2 ---------> 6 CO2 + 6 H2O + 30 ATP
Aldehydes get oxidized to acids.
Another name for acetic acid is vinegar. Fermentation process - sugar --> ethanol
Oxidation continues ethanol ---> ethanal ---> vinegar
The carbon that has the double bond with oxygen also has to have 2 other
Biochemically we see ketones
HCOOH methanoic acid aka formic acid If the H comes off it is called formate
H3CCOOH ethanoic acid aka acetic acid If the H comes off it is called acetate.
ACETATE IS EXTREMELY IMPORTANT IN BIOCHEMISTRY
Acetate is the precursor for
1. the Krebs Cycle aka Tricarboxylic Acid or Citric Acid Cycle Acetate comes into this pathway and 2 carbon dioxides come off every time the cycle turns and 10 ATP=s are formed. See sheet
2. synthesis of fatty acids
3. synthesis of sterols - cholesterol, bile acids, hormones
4. the formation of glycine, an amino acid.
Δ 9 organic chemistry
Polyunsaturated Fatty Acids
All three used to be called essential fatty acids. Now 18:2 and 18:3. Needed for growth.
Draw 18:2 ω6,9
Omega 3 Fatty Acids
Monkeys fed high cholesterol diets developed atherosclerosis giving rise to a correlation between high fat diets and heart disease. Eskimo diets were very high in fat, yet they had a low incidence heart attacks. Eskimo diets had a five fold excess of omega 3 fatty acids compared to the diets of the Danes. This prompted research into the omega 3 fatty acids.
fully Saturated Fatty Acids
Diets high in omega 3 fatty acids :
Diets too high in omega 3 fatty acids:
Trans Fatty Acids
Trans refers to the spacial arrangement of the carbon atoms. A trans configuration gives a 'kink' in the molecule. The trans formation is found in ruminant fat, made by microorganisms in thr rumen. The major source is due to an artifact in the hydrogenation of unsaturated fatty acids.
Trans fatty acids are metabolized like the saturated fatty acids. It is though that the trans may antagonize the metabolism of the essential fattya cids and make the deficiency worse.
Trans raises the LDL cholesterol levels and lowers the HDL cholesterol levels, has an increase in cancer. On autopsy 15% of the fatty acids were found to be trans.
C20 comes from arachidonic acid Put in where the double bonds would be if the prostaglandins come from arachidonic acid.
Function as hormones: raising or lowering blood pressure, constricting or dilating vessels, or muscle contraction.
Amines generally have an unpleasant odor.
Amines have NH2 groups. Amines are basic in nature. Amino acids have an acid group and an amine group. These are polar groups, so amino acids are soluable in polar solvents, ie blood.
BUN - blood urea nitrogen
Positive nitrogen balance means more proteins are being made rather than being destroyed.
Negative nitrogen balance means more proteins are being destroyed than being made. Anorexia and cancer give negative nitrogen balance.
Esters generally have a pleasant odor.
acid + alcohol -------> ester + water
Fatty acids + glycerol -------> triglyceride (what kind of structure do you think a TG is?)
Strawberry = ethyl butyrate
Apple = methyl butyrate
Rum = methyl formate (formic acid = methanoic acid)
Aspirin is an ester
Biochemically we see esters
C- O - C dimethyl ether C-C-O-C is ethyl methyl ether
The old anesthetic is diethyl ether. What does it look like?
Bunny - O - Bunny Ether Bunny
Wednesday, March 21, 2007 01:28:02 PM