The chemoselectivity
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This document discusses chemoselectivity and which functional groups react first when multiple groups are present. It also covers protecting groups used to control selectivity and different oxidizing agents for converting alcohols to aldehydes and ketones or acids, including Dess-Martin and Swern oxidations for primary alcohols and chromium and manganese agents for secondary alcohols. Lastly, it prompts the reader to think about selectivity considerations.
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2. Several heterocyclic aldehydes and aniline derivatives were synthesized and used to prepare Schiff bases. These include Schiff bases derived from 4-methylumbelliferone and N-methylpropane-1,3-diamine.
3. The Schiff bases were characterized using analytical techniques like NMR, MS and IR spectroscopy. They were then used to prepare transition metal complexes which will be explored for potential biological activities.
Click chemistry appliations in polymer science
1. Click chemistry describes high-yielding chemical reactions that can join small units together under mild conditions to form complex molecules. Reactions classified as "click" must be modular, wide in scope, generate no byproducts, and meet other criteria.
2. The copper-catalyzed azide-alkyne cycloaddition, or CuAAC, is a prototypical click reaction that is highly favorable thermodynamically and kinetically. It has found numerous applications in material science, including in adhesives, propellant binders, polymer modification, and surface functionalization of nanoparticles.
3. Other click reactions like thiol-ene have been used to synthesize hydrogels and dendrimers/
Protecting Groups (Examples)
The document discusses retrosynthetic analysis and protecting groups in organic synthesis. It provides 4 examples of retrosynthetic analysis where the forward synthesis is deduced by working backwards from the target molecule. The examples show how protecting carbonyl and hydroxyl groups is necessary to allow for certain reactions like Grignard and Friedel-Crafts reactions to produce the target molecule.
Drug design
drug design, target interactions, structure activity relationships, drug structure and types of drug designs.
FGIs
The document discusses functional group interconversions (FGIs) in organic synthesis. It defines FGIs as writing one functional group for another to help with retrosynthetic planning. FGIs are important for identifying suitable disconnections in retrosynthesis when a molecule contains multiple functional groups. The document categorizes common functional groups containing heteroatoms, such as carboxylic acids, aldehydes/ketones, and alcohols/amines. It also discusses methods for oxidizing and reducing functional groups, as well as removing functional groups altogether.
Ph.D. work ppt presentation
The thesis summarizes the design, diversity-oriented synthesis, and biological evaluation of novel quinolinyl heterocycles as potential antimycobacterial agents. Over 50 compounds were synthesized using simple reaction protocols. 40 compounds were screened for antimycobacterial activity against Mycobacterium smegmatis, with 20 showing activity. Compounds 89b, 89c, 89n and 89r were particularly promising, inhibiting growth by over 50% at concentrations under 70 μg/mL. These compounds also showed low cytotoxicity against human lung cells. Additional screening found some compounds to be active against bacteria and fungi. Compounds 89n, 89b, and 89c showed anti-inflammatory effects in a rat paw edema assay
Drug design
Molecular descriptors are numerical values that characterize molecular properties and structures. They can represent physicochemical properties or values derived from algorithmic techniques applied to molecular structures. Descriptors vary in complexity and computational requirements. Some are based on experimental data while others are algorithmic constructs. Two-dimensional (2D) descriptors are calculated from 2D structures and include counts, physicochemical properties, and topological indices. Three-dimensional (3D) descriptors encode spatial relationships and include fragment screens and pharmacophore keys.
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The chemoselectivity
- 2. The selectivity • Thisquestion arises from presence of more than one functional group.
- 3. The chemoselectivity • It is matter of reactivity ….
- 4. The chemoselectivity • Which is more reactive ??
- 8. Dianions • Last formed , react first ???? 16 25
- 13. Oxidizing agents • Oxidation of primary alcohols
- 14. Oxidizing agents • Oxidation of primary alcohols • Dess – Martin oxidation • Swern oxidation
- 15. Oxidizing agents • Oxidation of secondary alcohols to acids • Cr (VI) and Mn (VII) still the preferred agents.
- 16. Think bout it ?
- 17. Think about it ?