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Organic Chemistry Classes with structure

Organic Chemistry Classes “OCC”

When you are preparing for pharmacy examination, organic chemistry is very important to understand many biological interactions and drug binding concepts.

I will enumerate different organic classes with important tips about them. Here we go:

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Source: www.compoundchem.com

Alkanes

  • Also called paraffins, saturated hydrocarbons.
  • General formula: R-CH2-CH3.
  • Lipid soluble.
  • Common reactions: halogenation, combustion.
  • Chemically inert to air, heat, light, acids, bases.
  • Stable in vivo.

Alkenes

  • Also called olefins, unsaturated hydrocarbons.
  • General formula: R-CH=CH2. Lipid soluble.
  • Common reactions: addition of hydrogen or halogen, hydration (to form glycols), oxidation (to form peroxides).
  • Volatile alkenes and peroxides may explode in presence of O2 and spark
  • Stable in vivo.
  • Hydration, peroxidation, reduction may occur.

Aromatic hydrocarbons

  • Based on benzene.
  • Exhibit multicenter bonding. Lipid soluble. Common reactions: halogenation, alkylation, nitration, sulfonation. Chemically stable.
  • In vivo: hydroxylation, diol formation.

 

Alkyl halides

  • Halogenated hydrocarbons. General formula: R-CH2-X.
  • Lipid soluble.
  • ↑ degree of halogenation↑ Solubility.
  • Common reactions: dehyro-halogenation, nucleophilic substitution.
  • Stable on the shelf. Not readily metabolized in vivo.

Alcohols

  • Contains OH group.
  • May be primary (R-CH2-OH), secondary (R1/R2-CH-OH), or tertiary (R1/R2/R3-C- OH).
  • Alcohols are lipid soluble.
  • Low molecular weight alcohols are water soluble.
  • ↑ hydrocarbon chain length  ↓ water solubility.
  • Common reactions: oxidation, esterification.
  • Stable on shelf.
  • In vivo: oxidation, sulfation, glucuronidation.

Oxidation:

primary alcohol aldehydeacid.

Second aryalcoholketone.

Tertiary alcohol not oxidized.

Phenols

  • Aromatic compounds containing OH groups directly connected to aromatic ring.
  • Monophenols  one OH.
  • Catecholstwo OH.
  • Phenol (carbolic acid): water soluble.
  • By ↑ ring substitution ↓ water solubility.
  • Most phenols are lipid soluble.
  • Common reactions: with strong bases to form phenoxide ion, esterification with acids, oxidation to form colored quinones.
  • On the shelf: oxidation with air or ferric ions.
  • In vivo: sulfation, glucuronidation, aromatic hydroxylation, o-methylation.

Ethers 

  • General formula: R-O-R.
  • Lipid soluble.
  • Partially water soluble.
  • By ↑ hydrocarbon chain  ↓ water solubility.
  • Common reaction: oxidation to form peroxides (may explode).
  • In vivo: o-dealkylation.
  • Stability ↑ with size of alkyl group.

Aldehydes

  • General formula: R-CHO (contains a carbonyl group C=O).
  • Lipid soluble.
  • Low molecular weight aldehytes are also water soluble.
  • Common reactions: oxidation (to acids, in vivo and in vitro) and acetal formation.

Ketones

  • General formula: R-CO-R (contains a carbonyl group C=O).
  • Lipid soluble.
  • Low molecular weight ketones are also water soluble.
  • Non-reactive and very stable on the shelf.
  • In vivo: some oxidation or reduction.

Amines

  • Contain an amino group (-NH2).
  • Primary (R-NH2), secondary (R1/R2-NH), tertiary (R1/R2/R3-N), quaternary (R1/R2/R3/R4-N+ X-).
  • Lipid soluble.
  • Low molecular weight amines  water solubility.
  • By ↑ branching  ↓ water solubility (primary amines and most soluble).
  • Quaternary amines (ionic) and amine salts are water soluble.
  • Common reactions: oxidation (air oxidation on shelf), salt formation with acids.
  • Aromatic amines are ↓ basic↓ reactive with acids.
  • In vivo: glucuronidatin, sulfation, methylation.
  • 1ry: oxidative deaminatin.
  • 1y/2ry:  acetylation.
  • 2ry/3ry:  dealkylation.

Carboxylic acids

  • General formula: R-COOH (Carboxyl group –COOH).
  • Lipid soluble.
  • Low molecular weight acid and Na/K salts are water soluble.
  • Common reactions: salt formation with bases, esterification, decarboxylation.
  • Very stable on shelf.
  • In vivo: conjugation (with glucuronic acid, glycine, glutamine), beta oxidation.

Esters

  • General formula (R-COOR).
  • Lipid soluble.
  • Low molecular weight esters are slightly water soluble.
  • Common reaction: hydrolysis to form carboxylic acid and alcohol (in vivo by esterases / in vitro).

Amides

  • General formula: R-CONH2 or R-CONR1/R2 (lactam form).
  • Lipid soluble.
  • Low molecular weight amides are slightly water soluble.
  • No common reactions.
  • Very stable on shelf.
  • In vivo: enzymatic hydrolysis by amidases in the liver.

 

 

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