Lecture 4 Organics

Question 1

What are amides?

Answer 1

Strong smelling functional groups which replace hydrogen with a NH2 group

Question 2

What is the functional group of an amide?

Answer 2

R-NH2

Question 3

True or False? Amides are similar to alcohols?

Answer 3

True

Question 4

Is ammonia solution and ammonium hydroxide the same thing or different things?

Answer 4

The same thing

Question 5

Are amides weak or strong bases?

Answer 5

Weak bases and can act as buffers

Question 6

How many lone pairs do amides have?

Answer 6

One lone pair of electrons and therefore has a trigonal bipryamidal shape

Question 7

What is a primary amide?

Answer 7

When there is 1 carbon bonded to N

Question 8

What is a SECONDARY amide?

Answer 8

When there is 2 carbons bonded to N

Question 9

What is a TERIARY amide?

Answer 9

When there is 3 carbons bonded to N

Question 10

Amides are similar to what?

Answer 10

Carboxylic acids with the hydroxyl group being replaced with the amine group

Question 11

True or False? The chemistry of amides is similar to that of carboxylic acids

Answer 11

True

Question 12

Are amides less or more acidic than carboxylic acids?

Answer 12

Less acidic because the nitrogen is much less able to stabilise the negative charge

Question 13

Primary amides are formed by what?

Answer 13

Reacting a carboxylic acid with ammonia aka condensation reaction

Question 14

If the attacking group is an amine what is the product?

Answer 14

A secondary amide. aka condensation reaction, water is lost

Question 15

Is the amide bond or ester bond much more easily hydrolisable?

Answer 15

Amide bond due to the lower electronegativity of the nitrogen. This has important consequences for the amides in biological systems

Question 16

Secondary amides and esters are the basic compounds of what?

Answer 16

Many commercial polymeric compounds

Question 17

True or False? Amides hold many polymers together making proteins

Answer 17

True

Question 18

What is kevlar?

Answer 18

A tough amide polymer that gains its strength from the hydrogen bonds that occur between amide proteins and carbonyl groups

Question 19

What is switterion?

Answer 19

a molecule or ion having separate positively and negatively charged groups.

Question 20

What is the n-terminus?

Answer 20

The N-terminus is the start of a protein or polypeptide referring to the free amine group (-NH2) located at the end of a polypeptide.

Question 21

What are disulfide bridges?

Answer 21

A functional group with the structure R−S−S−R′. The linkage is also called an SS-bond or sometimes a disulfide bridge and is usually derived by the coupling of two thiol groups

Question 22

What are amino acids?

Answer 22

The building blocks of proteins

Question 23

What is the structure of an amino acid?

Answer 23

An R group, An acid group, A hydrogen, and An amino group all surrounding a carbon

Question 24

What gives amino acids their different properties?

Answer 24

The different R-groups. This also gives proteins their 3D shape and properties

Question 25

Are amines acidic or basic?

Answer 25

basic

Question 26

Are carboxylic acids acidic or basic?

Answer 26

Acidic

Question 27

What is the zwitterionic form?

Answer 27

Sits in between the extremes of the amino acids. Its charges balance to give a neutral compound that is soluble in water

Question 28

What are peptides?

Answer 28

Molecules containing at least one peptide bond (secondary amide between two amino acids)

Question 29

What are proteins?

Answer 29

Polypeptides constructed of many amino acids all held together by peptide bonds

Question 30

True or False? Breaking of a peptide bond is very slow in water

Answer 30

True

Question 31

True or False? Small peptides are never the basis for medicinal chemicals.

Answer 31

False

Question 32

How do we read the sequences of residues of amino acids?

Answer 32

From the N-terminus to the C terminus. | LHS to RHS

Question 33

How many different amino acids are there?

Answer 33

20

Question 34

How are proteins able to catalyse reactions?

Answer 34

Because proteins have complex three dimensional structures

Question 35

What do enzymes do?

Answer 35

Catalyse reactions that allow for life to occur.

Question 36

Are the peptide links in proteins floppy or stiff?

Answer 36

Floppy with free rotation about most bonds

Question 37

Interactions in the protein chain cause what?

Answer 37

Folding which forms the secondary structure

Question 38

Which interactions cause the secondary structure of proteins?

Answer 38

Non-covalent hydrogen bonding interactions give the a-helices and b-sheets in the secondary structure

Question 39

What does the tertiary structure of proteins depend on?

Answer 39

How the primary and secondary structures are arranged.

Question 40

What can the tertiary structure interactions be?

Answer 40

Hydrogen bonds, ionic, or covalent (disulfides) bonds

Question 41

How is the quarternary structure of proteins formed?

Answer 41

Several tertiary protein structures clump together.

Question 42

Where is energy stored in ATP?

Answer 42

In the phosphate bond