Nonlinear polycyclic diazaphenothiazinone scaffolds are an emerging class of heterocycles with promising biological activity. Palladium catalysis — particularly Buchwald–Hartwig C–N coupling and aminocarbonylation strategies — has been widely applied to install amido functionalities on heteroaromatic cores, enabling rapid access to libraries of amido derivatives for antimicrobial screening. This review summarizes palladium-based methods relevant to preparing amido derivatives of nonlinear diazaphenothiazinone, surveys the reported syntheses and preliminary antimicrobial findings, compares methods in a concise table format, and highlights gaps and opportunities for further medicinal chemistry studies.