Name Structure Aspirin (Acetylsalicyli c acid, ASA) Description Synthesis Mild analgesic (relieve Salicylic acid+ethanoic mild pain and anhydrideaspirin+ethanoic inflammation) acid Alcohol taken with aspirin increases the risk of stomach lining bleeding (synergistic effect) - Carboxylic acid Phenyl group Ester Isolation of aspirin: Products cooled for crystallizationsuctio n filtered and rinsed with cool water Recrystallization Aspirin is recrystallized when added to hot ethanol. Can be filtered out. Melting point and IR spectroscopy (Condensation) Reagents: Conc. H2SO4 + Heat Drugs containing acidic and basic groups can be modified to increase their solubility in aqueous solutions. C6H4(OCOCH3)COOH + NaOH → C6H4(OCOCH3)COO-Na+ + H2O Advantages/Disadvantag es Ads. -Non-narcotics (do not affect the functioning of the brain) -Anti-pyretic to reduce fever -Anti-inflammatory agent -Anti-platelet agent to prevent abnormal blood clotting (anticoagulant) Dis. -Cause upset stomach -Cause ulceration of stomach -Allergic reactions -Reye’s syndrome Penicillin - R group Carboxylic acid Beta-lactam ring Beta-lactam ring is the four-membered ring structure consisting of one N atom and three C atoms. It contains a cyclic amide group. The bond angle is 90, but it should be 120 and 109.5 according to VSEPR theory. Due to high ring strain, the betalactam ring breaks relatively easily. Penicillin inhibits the development of cross links that are used to reinforce bacterial cell walls weakened cell wall allows water to enter by osmosis increased osmotic pressure causes the bacterium to rupture. Modifying penicillin G -Some bacteria had developed resistance to penicillin G by synthesizing the enzyme penicillinase, which could deactivate penicillin by opening the betalactam ring. 1. To make it resistant to stomach acidity 2. To overcome antibiotic resistance in bacteria Opiate 1.Morphine Strong analgesics (used for the relief of severe pain) - Arene Ether Alkenyl Hydroxyl (2) Tertiary amino Bind to opiate receptors in the brain and influence the perception of pain without depressing the nervous system They need to cross the blood-brain barrier before binding to the receptor. BBB is nonpolar (made of lipids). Narcotics The narcotic drugs derived from opium are mainly morphine, and its derivatives are codeine and heroin. Codeine and heroin are semi-synthetic drugs. Adv. -Used to manage severe pain Dis. -Can lead to addiction (dosage must be strictly regulated) Opiate 2.Codeine Strong analgesics (used for the relief of severe pain) Bind to opiate receptors in the brain and influence the perception of pain without depressing the nervous system - Arene Ether (2) Alkenyl Hydroxyl (1) Tertiary amino Opiate 3.Heroindiamorphine Arene Ether Alkenyl Since methyl ether in codeine is less polar than the hydroxyl group in morphine, codeine is more effective at crossing BBB. They need to cross the blood-brain barrier before binding to the receptor. BBB is nonpolar (made of lipids). Strong analgesics (used for the relief of severe pain) - Morphine is converted into codeine by methylation. Methylation involves the conversion of one of the hydroxyl group in morphine into a methyl ether in codeine. Bind to opiate receptors in the brain and influence the perception of pain without depressing the nervous system Narcotics The narcotic drugs derived from opium are mainly morphine, and its derivatives are codeine and heroin. Codeine and heroin are semi-synthetic drugs. Adv. -Used in cough and diarrhea medications An esterification reaction involving ethanoic acid converts both of morphine’s hydroxyl groups into ester groups. Dis. -Addiction -Weakest effects as an analgesic Narcotics The narcotic drugs derived from opium are mainly morphine, and its derivatives are codeine and heroin. Codeine and heroin are semi-synthetic drugs. Adv. - Ester (2) Tertiary amino They need to cross the blood-brain barrier before binding to the receptor. BBB is nonpolar (made of lipids). Diamorphine is a prodrug, meaning that it is converted back into morphine once it has crossed BBB. -Relieve pain Dis. -Very addictive -Abused narcotic -Strongest effects as an analgesic
