This review explores the development, modification, and optimization of potent active compounds using combinatorial synthetic methods that incorporate phytoconstituents from plant extracts, aiming to enhance efficacy and mitigate resistance. Attenuated total reflectance-Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry (GC-MS), and antibacterial data from the literature were employed to validate these strategies. The methodology emphasized precise harvesting, pre-treatment, and extraction processes to ensure the quality and efficacy of the plant extracts. Various extraction methods and solvents were used to isolate specific phytoconstituents, followed by further purification through chromatography. The review proposes three strategies: (i) reacting single or multiple plant extracts with reagents such as acids or catalysts, (ii) combining plant extracts with ineffective drugs to induce structural changes that enhance antibacterial efficacy, and (iii) integrating plant extracts with drugs not originally intended for the target disease to explore new structural functionalities. Significant findings include synergistic effects observed when Psidium guajava and Calotropis procera extracts were combined with antibiotics, leading to substantially increased zones of inhibition against resistant bacteria. GC-MS analysis identified numerous bioactive compounds, some of which with known anticancer properties, suggesting potential applications beyond antibacterial effects. These innovative combinatorial approaches demonstrate the potential to yield new compounds with enhanced pharmacological properties, highlighting the critical role of plant extracts in drug discovery and development. This review underscores the promise of harnessing natural products to combat multi-drug resistance, paving the way for advanced research and development in pharmaceutical applications.

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