E. serratus tropical flowering tree belong to the family elaeocarpaceae. The fruit of the tree is frequently consumed by people and is also used in folk medicine. It is also known as Ceylon olive. According to studies, E. serratus has anti-diarrheal, analgesic and anti-arthritic properties. Investigations on other effects such as antioxidants, Antimelanogenesis and antimicrobial studies have also been conducted. The present review is an effort to give detailed survey of the literature on photochemistry of E. serratus.

A series of substituted dihydro-1, 2-oxazole benzopyran-2-one (SR1-SR6) were synthesized through the intermediate substituted benzopyran-2-one chalcones and were characterized using spectral analysis.   Compounds were docked with receptor DNA Gyrase B (PDB code: 5L3J) to know its interaction and binding energy; ranges -3.38 to -2.15 kcal/mol. Further these compounds were tested for antibacterial activity using tube dilution method and MIC values were observed; ranges 3.12 to 25 µg/ml. Compound 3-(5-(m-tolyl)-4,5-dihydroisoxazol-3-yl)-2H-chromen-2-one (SR3) showed the best interaction with binding energy -3.38 kcal/mol and antimicrobial activity having MIC 3.12 µg/ml. GRAPHICAL ABSTRACT

A new series of dihydro-1, 2-oxazole coumarin derivatives (SR1-SR10) was prepared using a multi-step reaction. The syntheses of intermediates coumarinyl chalcones and final compounds were characterized by IR, Mass, and 1 H NMR spectra. The final compound’s SR1-SR10 binding mode and its inhibitor susceptibility were studied by molecular docking with the receptor DNA gyrase B (PDB code: 5L3J). It is responsible for catalyzing changes during DNA replication and validated targets for antibacterial molecules. The docking score of compounds SR1-SR10 ranges from -4.18 to -2.15 kcal mol-1. Among all these compounds, chloro-substituted dihydro isoxazole chromen-2-one (SR10) showed the best docking score with -4.18 kcal mol-1. SR10 interacted with the ATP-binding site of E. coli DNA gyrase B through a hydrogen bond with GLY77 and hydrophobic bond, charged negatives and polar interaction. SR1-SR10 antibacterial inhibitory property by tube dilution method was performed, and its minimum inhibitory concentrations (MIC) were observed. The MIC values of (SR1-SR10) range from 3.12 to 25 µg mL-1. Compounds SR3 and SR10 showed significant antibacterial activity with a MIC value of 3.12 µg mL-1