Drug Organic Chemistry

1
Drug (Organic) Chemistry
2
What is an Organic Compound?

• Must contain carbon and hydrogen
• Have covalent bonds
• Have low melting and boiling points
• Burn in air (oxygen)
• Are soluble in nonpolar solvents
• Form large molecules using chains and rings of
  carbon

3
(No Transcript)
4
Alkanes

• Contain C and H only
• Contains C-C single bonds in chains or rings
• Have 4 bonds to every carbon (C) atom
• Hydrogen has one bond
• General formula for chains CnH2n2
• Name chain length -ane

5
Complete Structural Formulas

• Shows the bonds between each of the atoms
  example methane, CH4
• H H
• H C H H C H
• H H

6
Formulas of Carbon Chains

• A single bond between two carbon atoms possesses
  free rotation which allows molecules to have
  different conformations, or different
  orientations.

• Two of the many conformations of butane are shown
  above. All the possible conformations are
  constantly being converted into each other
  through rotations.
• Several conformations of butane are also shown
  below as ball and stick models

7
Condensed Structural Formulas

I, II, and III represent the same conformation,
shown in different orientations. IV is a
different conformation. V does not specify a
conformation. VI is an expanded structural
formula and VII is a condensed structural formula.
8
Skeleton and Line Formulas

• Two additional types of structural
  representations are also sometimes used
  skeleton and line structural formulas

• In a line formula, a carbon atom is assumed to be
  present at every intersection and at the terminal
  ends of lines.

9
Condensed Formulas of Alkanes
10
(No Transcript)
11
Branched Chain Isomers

• Isomers have the same molecular formula but
  different structures
• Example pentane, C5H12, has 3 isomers

12
Naming Branched Isomers

• Find the longest continuous chain use it as the
  alkane chain name
• Number the chain so the branch has the lowest
  number
• Indicate the branch length with prefixes from the
  table provided
• If a branch appears more than once use di, tri,
  etc. to indicate the number of branches
• Example (a) pentane (b) 2-methylbutane (c)
  2,2-dimethylpropane

13
(No Transcript)
14
Types of Branches in Isomers

• Hydrocarbon or Alkyl groups are generically
  represented by R
• Branches can be classified by the number of
  carbons attached primary, secondary, tertiary or
  quaternary

15
Learning Check

• A. What is the condensed formula for
• What is its line formula?
• C. What is its name?

16
Alkenes and Alkynes

• Contains CC double or triple bonds (called
  p-bonds)
• Have 4 bonds to every carbon and 1 bond to H
• General Formula CnH2n and CnH2n-2
• Name chain length -ene or -yne

17
Alkenes Isomers

• Position of the multiple bond is indicated by the
  lowest number of carbons from one end of the
  chain
• Example (a) 1-butene (b) 2-butene (c) 1-butene

18
Learning Check

• Consider the molecule 2-methyl-2-butene
• What is the Lewis structure?
• What is its condensed formula?
• What is its line structure?

19
Cycloalkanes

• Three or more C-C single bonds connected in a
  ring
• General Formula CnH2n name Cyclo chain
  length
• Branches are numbered and named in the usual way

20
Aromatic Compounds

• General Formula CnHn branch name benzene
• Resonance structures are needed to diagram bonds
• C-C bonds are all equal in length and are NOT
  alternating double and single bonds
• Electrons are delocalized above below the ring

21
Aromatic Compounds

• Branches are numbered and named in the usual way
• Some aromatics have common names
• Aromatics with four or more fused rings of
  benzene cause cancer (tobacco smoke, auto
  exhaust, etc.)

22
Alcohols

• General Formula, R-OH Name, chain length -ol
• The position of the -OH is indicated by its
  location on the carbon chain
• The hydroxyl group is chemically similar to
  water and has hydrogen bonding, so small chain
  alcohols dissolve easily

23
Examples of Alcohols
24
(No Transcript)
25
Ethers

• General Formula, R-O-R
• Name short chain -oxy long chain -ane
• Ethers are polar but have no hydrogen bonding so
  boiling point increases with molar mass
• Formed by dehydration of alcohols
• 2 CH3OH ---gt CH3-O-CH3 H2O

26
Carbonyl Compounds
27
Aldehydes

• General Formula, RC(O)H contains a carbon with
  a CO bond also bonded to an H
• Name chain length -al
• Alcohols can be oxidized to aldehydes and
  aldehydes can be oxidized to carboxylic acids

28
(No Transcript)
29
Ketones

• General Formula, RC(O)R contains a CO bond
  with two hydrocarbon groups attached
• Name chain length -one with the position of
  the carbonyl group identified by a number
• The CO bond is polar but creates no hydrogen
  bond
• Ketones come from oxidation of 2 alcohols
• Ketones cannot be oxidized to acids

30
(No Transcript)
31
Learning Check
Identify all functional groups in each of the
following
32
Carboxylic Acids

• General Formula, RC(O)OH contains a CO bond
  and a C-O bond and an -OH bond
• Name chain length -oic acid
• They are more polar than aldehydes and ketones
  and can hydrogen bond
• They are weak acids that partially ionize
• CH3CO2H H2O lt---gt CH3CO2-1 H3O
• Soaps are long chain carboxylate salts
  C18H35CO2-1

33
(No Transcript)
34
(No Transcript)
35
Esters

• General Formula, RC(O)OR contains a CO bond
  and a C-O bond and an -O-R bond
• Name chain length not touching CO chain
  length -onate
• Prepared by reacting a carboxylic acid and an
  alcohol
• CH3CO2H CH3OH ---gt CH3CO2CH3 H2O
• Many have fruity odors

36
Learning Check

• Draw the condensed or line structure of the
  following compounds
• Methoxybutane
• 3-pentanone
• Ethanoic Acid
• Butyl pentanoate

37
Amines

• General Formula R-NH2, R2NH or R3N
• Name each carbon chain is named in alphabetical
  order amine is added at the end
• They are more less polar than carboxylic acids
  but can hydrogen bond
• They are weak bases that partially ionize
• CH3NH2 H2O lt---gt CH3NH31 OH-
• They are found in most drugs

38
Structures of Amines
39
Amino Acids and Amides

• Amino acids have both an amine and carboxylic
  acid
• Amino acids are the building blocks of proteins
• Amides come from the condensation of a carboxylic
  acid and an amine
• Amides contain a CO group connected to an NH

40
Learning Check
Identify all the functional groups in each of the
following