hydrolysis

hydrolysis

1. NAME: SAMER AZIZ ROLL NO: DE-068 SUBJECT: PHYSICAL PHARMACY HYDROLYSIS

2. HYDROLYSIS: DEFINATION : the chemical breakdown of a compound due to reaction with water is called hydrolysis TYPES ON THE BASIS OF CHEMICAL REACTION: Ionic hydrolysis Molecular hydrolysis

3. Ionic hydrolysis It occur when the salt of weak acids and weak bases interact with water to give either alkaline or acidic solution Molecular hydrolysis: It is much slower and irreversible process it is catalized by hydrogen or hydroxyl ion e.g. the local anesthetics

4. TYPES OF HYDROLYSIS:(ON THE BASIS OF DRUG DEGRADATION) ESTER HYDROLYSIS : An acid-catalyzed  ester hydrolysis  involves the breakdown of an  ester  into its corresponding carboxylic acid and alcohol. This is done by the addition of a water molecule, using an acid as a catalyst .

5. EXAMPLE OF DRUGS WHICH UNDER GO ESTER HYDROLYSIS: Tetracaine Atropine Physostigmine Procaine Asprin

6. AMIDE HYDROLYSIS:  when  amides  are hydrolysed in the presence of dilute acids such as dilute hydrochloric acid. The acid acts as a catalyst for the reaction between the  amide  and water .

7. EXAMPLES OF DRUGS WHICH UNDERGO AMIDE HYDROLYSIS : Dibucaine Ergometrine Chloramphenicol Niacinamide Barbiturates

8. RING HYDROLYSIS: Hydrolytic reactions in certain drugs proceed by ring cleavage with subsequent attack by hydrogen or hydroxyl ions .

9. DRUGS UNDER GO RING HYDROLYSIS: Bezodiazepines ( such as nitrazepam and chlordiazepoxide ) Penicillin cephalosporins