Synthesis and molecular docking studies of xanthone attached amino acids as potential antimicrobial and anti-inflammatory agents

摘要

A series of novel xanthone conjugated amino acids were synthesised and characterised by analytical and spectroscopic methods. All the synthesized analogues (>2–23) were screened for their in vitro antimicrobial and anti-inflammatory activities. Compounds >7, >8, >9, >12, >18, >19, >20, >21 and >23 showed excellent antimicrobial activities compared to antibacterial and antifungal reference drugs gentamicin and bavistin, respectively. Compounds >7–12 and >18–23 showed good anti-inflammatory activity compared to a standard drug, indomethacin. The preliminary structure–activity relationship revealed that tryptophan, tyrosine, phenylalanine, proline and cysteine conjugated compounds showed excellent antimicrobial and anti-inflammatory activities. This may be explained by the contribution of aromaticity and hydrophobicity of amino acids. Molecular docking studies were performed for all the synthesised compounds, among which compounds >20, >21 and >23 showed the highest docking scores for antimicrobial activity while compounds >9, >20 and >22 showed the highest docking scores for anti-inflammatory activity. Different amino acids conjugated xanthone derivatives were synthesized and evaluated for their in vitro biological activities. The conjugation was found to play a major role in improving the biological activities of those compounds.