![Etidocaine
IUPAC-
N-(2,6-dimethylphenyl)-2-[ethyl(propyl)amino]butanamide
Purushotham KN, SACCP, ACU.
12
CH3
NH
CH3
N
O
CH3
CH3
CH3](https://image.slidesharecdn.com/newmicrosoftpowerpointpresentation-200824115130/85/Local-Anesthetics-by-Purushotham-KN-SACCP-ACU-2020-21-12-320.jpg)
Local Anesthetics by Purushotham KN, SACCP, ACU, 2020-21
- 1. LOCAL ANESTHETICS Presented by- Purushotham KN Assistant Professor SACCP, ACU, B.G Nagara Ay-2020-21
- 2. Local anesthetics are drugs which reversibly prevent the generation & propagation of active potentials in all excitable membranes including nerve fibers by stabilizing the membranes. Local Anesthetics are used to abolish the sensation of pain in a restricted area of the body and for minor surgical operations, when loss of consciousness is not desired. Purushotham KN, SACCP, ACU. 2
- 3. The area determined by the site and the technique of administration of anesthetic agents. The main uses are as follows: Surface / Topical anesthetics Local anesthesia is applied to Mucous Membrane. Ex: Larynx, Damaged skin surface Infiltration anesthetics Local anesthesia is injected subcutaneously to paralyze the sensory nerve ending Ex: an area to be incised, Tooth extraction. Nerve block anesthesia Local anesthesia is injected close to the nerve trunk. Cavdal anesthesia Local anesthetic into the caudal canal, the sacral portion of the spinal canal. Epidural anesthesia Anesthesia that creates a band of numbness from your bellybutton to your upper legs. Spinal anesthesia Purushotham KN, SACCP, ACU. 3
- 4. Chemical Classification 1. Esters 1. Amino alkyl esters of PABA 1. Procaine 2. Chloroprocaine 3. Tetracaine 4. Butacaine 2. Alkyl esters of amino benzoic acid 1. Orthocaine 2. Benzocaine 3. Butylamino benzoate 3. Esters of benzoic acid 1. Cocaine 2. Piperocaine 3. Hexylcaine 4. Piperocaine Purushotham KN, SACCP, ACU. 4
- 5. 2. Amides 1. Aminoacyl amides 1. Lidocaine 2. Prilocaine 3. Bupivacaine 4. Etidocaine 5. Mepivacaine 2. Amino alkyl amides 1. Cinchocaine / Dibucaine Purushotham KN, SACCP, ACU. 5
- 6. 3. Urethanes 1. Diperodon/Diperocaine 4. Aminoketones 1. Falicaine 2. Dyclonine 5. Aminoethers 1. Chlorobutanol 2. Eugenol 3. Dimethisoquin 6. Miscellaneous agents 1. Benzyl alcohol 2. Articaine Purushotham KN, SACCP, ACU. 6
- 7. SAR of Local Anesthetics SAR of Local Anesthetics containing an ester linkage General structure of LA containing an ester linkage Purushotham KN, SACCP, ACU. 7 Aryl--C--x--Aminoalkyl side chain Aromatic group Ester Linkage Aminoalkyl group O
- 8. Aryl group An aryl radical attached directly to the carbonyl results into a conjugation which in terms enhances local anesthetic activity. The aryl substituents which increase the electron density of the carbonyl oxygen & enhances activity. Eg: alkoxy/ amino/ alkylamino at ortho or para position. Purushotham KN, SACCP, ACU. 8
- 9. Bridge ‘X’ The X may be carbon, nitrogen, oxygen or sulphur. The nature of ‘X’ affects duration of action and relative toxicity. Amino alkyl group The amino group is considered as the hydrophilic part of the molecule. The activity decreases the irritation property increases in following order. Primary < secondary < Tertiary Amine The alkyl position only influence the lipid solubility. Purushotham KN, SACCP, ACU. 9
- 10. SAR of Local Anesthetics containing an amide linkage Aryl group The alkyl substitution at ortho/ para position, enhances the activity. It provides steric hindrance to the hydrolysis of the amide linkage and contributes to the lipid solubility of molecule Substituent ‘X’ In general ‘X’ May be Carbon – Isogramine Oxygen – Lidocaine Nitrogen – Phenacaine Amino alkyl group The nature and its relative contribution to activity is same as in the compounds containing an ester linkage. Purushotham KN, SACCP, ACU. 10 CH3 CH3 NH N O CH3 CH3 Aryl group Substituted 'X' Amino alkylgroup Lidocaine Aryl---NH--C--Aminoalkylgroup X General Structure
- 11. Structures of Amide based LA Lignocaine IUPAC- 2-(diethylamino)-N-(2,6dimethylphenyl)acetamide Purushotham KN, SACCP, ACU. 11 CH3 NH CH3 N O CH3 CH3
- 12. Etidocaine IUPAC- N-(2,6-dimethylphenyl)-2-[ethyl(propyl)amino]butanamide Purushotham KN, SACCP, ACU. 12 CH3 NH CH3 N O CH3 CH3 CH3
- 13. Purushotham KN, SACCP, ACU. 13 NH CH3 NH O CH3 CH3 PRILOCAINE IUPAC- N-(2-methylphenyl)-2-(propylamino)propanamide
- 14. MEPIVACAINE IUPAC – N-(2,6-dimethylphenyl)-1-methylpiperidine-2-carboxamide Purushotham KN, SACCP, ACU. 14 NH CH3 O CH3N CH3
- 15. Structures of Ester Based LA Purushotham KN, SACCP, ACU. 15 O O N CH3 CH3 NH2 O O N NH2 CH3 CH3 O O N CH3 O N O CH3 O CH3 O Procaine Piperocaine Butacaine Cocaine
- 16. Reference 1. Wilson and Griswold 2. Burger THANK YOU Purushotham KN, SACCP, ACU. 16