Theses (MSc. Analytical & Pharmaceutical Chemistry)

In this study, six chalcones containing methyl and hydroxyl substituents at meta positions in aromatic rings; (E)-3-phenyl-1-(m-tolyl)prop-2-en-1-one (C-01), (E)-1-phenyl-3-(m-tolyl)prop-2-en-1-one (C-02), (E)-1,3-di-m-tolylprop-2-en-1-one (C-03), (E)-1-(3-hydroxyphenyl)-3-phenylprop-2-en-1-one (C-04), (E)-3-(3-hydroxyphenyl)-1-phenylprop-2-en-1-one (C-05) and (E)-1,3- (3-hydroxyphenyl) prop-2-en-1-one (C-06) were synthesised using Claisen-Schmidt reaction of substituted acetophenones and benzaldehydes at room temperature. All the synthesised compounds were characterised by spectroscopic techniques including infrared (IR), ESI-MS, UV-visible and nuclear magnetic resonance (1HNMR). The synthesised chalcones were tested for their anti-inflammatory activities using Greiss assay on mouse macrophages (RAW 264.7 cells). The results showed that presence of methyl (-CH3) and hydroxyl (-OH) substituents improved the anti-inflammatory activity of chalcones. Hydroxyl substituted chalcones showed higher anti-inflammatory activity compared to methyl substituted chalcones. Among the hydroxy-substituted chalcones, the (E)-1,3-bis (3-hydroxyphenyl) prop-2-en-1-one (C-06) was the most potent with an IC50 value lower than 6.25 μM. This compound was further tested for its influence on expression of cytokines using multianalyte ELISA array kit. This chalcone significantly reduced the elevated levels of inflammatory cytokines (IL-6, IFN-γ, TNF-α and G-CSF). Key words: substituted chalcones, anti-inflammatory activity, cytokines, and ELISA array kit.

The discovery of new therapeutic agents for inflammatory disorders has attracted more attention in recent years. Chalcone term is given to the flavonoid compounds bearing the 1,3-diphenyl-2-propen-1-one framework. Generally, chalcones are precursors of flavonoids with two aromatic rings joined together through three carbons, α, β-unsaturated carbonyl system. In plants, chalcones are converted to the respective (2S)-flavanones by enzymatic reaction of chalcone isomerase. Based on the close chemical and biogenetic relationship between flavanones and chalcones, they are considered as natural products. For anti-inflammatory activity of chalcones, activated macrophages play an important role and compounds with that inhibit nitro oxide production by macrophages have been found potential for the prevention and treatment of inflammatory disorders. Some functional groups such as dimethylamine, methoxy and butoxy groups increase the electron density of the B-ring resulting in significant loss of anti-inflammatory activity. Therefore, in this project we synthesised five compounds for chalcones containing halogens (-Cl, -F) at meta-positions on aromatic rings in chalcones and tested for their anti-inflammatory activity. The synthesized compounds were purified by column chromatography and characterised by 1H-NMR, 13C-NMR, FTIR, Mass and UV spectra. Further evaluation of their in vitro anti-inflammatory activity were carried out using RAW 264.7 mouse macrophages. The test dose of chalcones were determined was cytotoxicity (MTT) assay on RAW264.7 mouse macrophages. The results showed that the halogen substitution at meta-positions on aromatic rings improved the anti-inflammatory activity for the compound (E)-1,3-bis(3-chlorophenyl) prop-2-en-1-one (III) shows the best activity. The table below showed the compounds activity with IC50 values. Keywords: Chalcones, m-chlorobenzaldehyde, m-chloroacetophenone, Ethyl alcohol, Anti-inflammatory activity, RAW 264.7 cells