Novel (4R,12aS)-7-methoxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido-[1',2':-4,5]-pyrazino[2,1-b][1,3]oxazine-9-carboxylic acid (L) was synthesized and characterised. The interaction between bovine serum albumin (BSA) with L was scrutinized by steady-state fluorescence spectroscopy, fluorescence anisotropy, fluorescence lifetime, and molecular docking methods. The fluorescence titration experiments of BSA resulted in fluorescence quenching with the incremental addition of L. The conformational binding of L to BSA has been investigated by molecular docking analysis. The molecular probe's best conformation showed the affinity as free binding energy release of -7.93 Kcal/mol. The docking analysis confirms that ligand binds in the near vicinity of TRP-213 in the binding pocket of subdomain IIA.