Exam 2 ochem

Carbonyl
A carbon oxygen double bond
-4 classes of carbonyls
Aldehyde
Product of oxidizing a primary alcohol
Type of carbonyl
Oxygen and hydrogen bonded to an end carbon
O2 must be double bond
-anal suffix
Ketone
Type of carbonyl
Oxygen and hydrogen bonded to a middle carbon
O2 must be double bond
-anone Suffix
Benzaldehyde
Benzene ring w an aldehyde on it
Found in flavorings
Aldehydes take precedence
Aldehydes take precedence
names for Sugars
saccharides, carbohydrates,
Different types of simple sugars (monosaccharides)
glucose (dextrose), fructose, galactose
Different types of disaccharides (complex sugars)
Sucrose, Maltose, Lactose
(enzymes: sucrase, maltase, lactase that break these down)
Many disaccharides and monosaccharides tend to polymerize…these are called:
poly saccharides
Disaccharides are made up of two monosaccharides with the exclusion of H20….this type of bond is called?
Glycoside bond
Glycoside bond means…
the bonding of two simple sugars, typically at the first and fourth carbon with the exclusion of a water molecule
-the sugar must exist in the hemiacetal form
Hemiacetal form of sugar
the ring form of sugars (the most commonly found form of sugars), can be either beta or alpha, depending on the location of the OH group on the last carbon (alpha is down, beta is up)
-the fifth carbon bonds to the 1st (aldehyde carbon)
-the molecule loses the oxygen double bond on the aldehyde
beta vs. alpha rings
beta: OH on 6th carbon is up
Alpha: OH on 6th carbon is down
Forms sugar can exist in:
Open chain form, beta hemiacetal form, alpha hemiacetal form
**Chirality? –> enantiomers and diastereomers
Chirality
for a center atom to be chiral, it must have four different groups bonded to it
certain molecules exist in a “left handed or right handed” form
its a property of assymetry
An object or a system is chiral if it is not identical to its mirror image, that is, it cannot be superposed onto it.
-chirality leads to enantiomers and diastereomers
D vs. L
describes the chirality of the second to last carbon (on a sugar)
D means the OH group is on the right
L means the OH group is on the left
enantiomers
two molecules that appear to be mirror images but are chiral
diastereomers
At least one of the chiral centers of a molecule are switched from the original molecule, but not all of them can be switched.
Tollen’s reagent (making silver
-REQUIRES an aldehyde (in this case sugar was used)
-requires a catalyst and silver ion (Ag+)
Take away 2 hydrogens or add oxygen
requires (this is an oxication reaction)
makes silver
Hydrogenation (reduction)of an aldehyde or a ketone
-add two Hydrogens or take away O2
-requires Hydrogen and a catalyst
Benedict’s test
require’s a sugar w/ a free carbonyl (aldehyde, all simple sugars-referred to as reducing sugars)
when sugar reacts with benedict’s test, the color changes from blue-red (and everythin in b/w)
This can be used to indicate excess sugar in blood or urine
Starch acts like a nonreducing sugar due to eventual termination of the branching
Maltose
GLU[alpha1,4]GLU
Isomatlose
GLU[alpha1,6]GLU
-occurs in amylose when branching to make amylopectin
Starch
amylose and amylopectin
Polysaccharides (4 of them)
starch
ribose
2-deoxyribose
glucosamine (chitin)
Honey
50%glucose
50% fructose
**normally these bond to become sucrose, table sugar
**enzyme in bee spit allows for these to to exist without bonding, referred to as hydrolizing (adding in H20 that would normally be cut out in bonding process)
sugars typically exist in ______ forms
3
breakdown of glucose in human body
-due to metabolism and enzymes, aldoase
glucose>fructose>dihydroxy acetone>glyceradlehyde> CO2 acetate>CO2 + H2O
Sucrose
GLU[alpha1,beta2]FRU
(poly)Cellulose
*similar to maltose, but beta forms of glucose are used
GLU[beta1,4]GLU
Lactose
GAL[beta1,4]GLU