"Organic Synthesis of aromatic compounds"
Starter 1) Suggest a two-step synthesis for 3- aminopropanoic acid from 3- bromopropanol. 2) Suggest a two step synthesis for butanol acid from ethyl butanoate. Organic Synthesis of aromatic compounds L.O.: Devise multi-stage synthetic routes for preparing aromatic organic compounds. Structures of benzene and 3-chloronitrobenzene Converting benzene into nitrobenzene Chlorination of an aromatic ring Task: Propose a retro-synthesis of paracetamol Chirality in pharmaceutical synthesis • Explain that the synthesis of pharmaceuticals often requires the production of a single optical isomer. • Explain that synthetic molecules often contain a mixture of optical isomers, whereas natural molecules often have only one optical isomer. • Explain that the synthesis of a pharmaceutical that is a single optical isomer increases costs, reduces side effects and improves pharmacological activity. • Describe strategies for the synthesis of a pharmaceutical with a single optical isomer. N Very potent M3 antagonist. + O N HO O Clinical candidate for COPD Task: 1) Dr Bravo synthesised the above compound as a mixture of enantiomers. In pairs discuss the disadvantages of using the mixture of enantiomers as a clinical candidate for COPD. 2) In pairs discuss possible solutions to overcome the problems aforementioned. 1) Disadvantages: o One of the enantiomers may have a harmful effect o Larger dose needed. 2) o Purifying the mixture using chiral HPLC o Synthesise a single chiral isomer Modern chiral synthesis How to prepare a single chiral isomer: o Using enzymes. o Chiral pool synthesis (starting from chiral molecules) o Use transition element complexes. Stereoisomers of thalidomide Pharmacological activity depends on whether or not a drug can interact with a receptor site in a biological system. Structure of ibuprofen, used in many medicines to relieve pain