Several new xylenyl-spaced bis-dihydrazothiazoles 6a-e and bis-dihydrazothiazolones 9a-e were synthesized by the simple reaction between bis-thiosemicarbazone 3 as a common synthetic scaffold, with two series of hydrazonoyl halides derivatives 4a-e and 7a-d. The chelation ability of these novel bis-dihydrazothiazole derivatives to perform as neutral tridentate ligands and coordinate to transition metal ions; Fe(III), Co(II), or Zn(II) through azomethine-N, thiazole-S, and azo-N atoms to form metal complexes with a metal/ligand ratio of 2:1 was elucidated. Diffused reflectance, magnetic moment, 1HNMR, FT-IR, TGA, and molar conductivity, were used to interpret the structures of all new xylenyl-spaced bis-heterocyclic compounds and their metal chelates. In-vitro, antibacterial and antiviral screening of these innovative xylenyl-spaced bis-dihydrazothiazole derivatives, as well as a selected group of their transition metal chelate complexes [M2L], were inspected, and the data was evaluated in comparison to those of Ketoconazole and Gentamycin as antimicrobial control standards using the agar well diffusion assay protocol against a selected group of fungal and bacterial species. Several compounds displayed respectable to great antimicrobial behavior against the examined microbial species. Bis-dihydrazothiazole 6c, particularly, showed exceptional inhibition of both C. albicans and E. coli. However, bis-dihydrazothiazolone 9b showed excellent inhibition of A. fumigatus. Additionally, amongst the three synthesized metal complexes [M2L], only the zinc complex, [Zn2L] showed remarkable inhibition of both C. albicans and S. typhimurium and was even more potent than the free ligand, 9a itself.