The present invention provides the synergistic combination of a naturally derived novel antibacterial agent Malabaricone B of Formula 1 from the species of Myristica malabarica and FDA approved conventional antibiotic gentamycin for the enhanced activity against antimicrobial resistant superbugs. The present invention also discloses the detailed In-vitro and in-vivo screening of the compound in various gram positive and negative bacterial strains including MDR and well explains the antibacterial efficacy of the compound thereof. In vivo studies disclose that the compound is as effective as the existing drug vancomycin. Clinical relevance of the disclosed molecule is an added advantage in terms of lower dose administration and short exposure time for excellent activity compared to existing antibiotics. In particular the present invention provides an efficient naturally derived novel drug lead for the treatment of MDR infections.