A series of structurally characterised, monovalent metal-halide complexes incorporating neutral amidine and guanidine ligands is reported. N,N′-diphenylbenzamidine reacted with copper(I) chloride to afford the bis-ligand complex [CuCl(PhC{NPh}{NHPh})₂]₂ (1), that exists as a chlorine bridged dimer in the solid state, with a non-symmetrical distribution of NH⋯Cl interactions within the ‘Cu₂Cl₂’ metallacycle. In contrast, only one equivalent of the guanidine, Me₂NC{NⁱPr}{NHⁱPr} (2), is coordinated in the copper(I) iodide complex [CuI(Me₂NC{NⁱPr}{NHⁱPr})]₂ (3), which was also isolated as the dimer with bridging halide atoms. The molecular structure of the bicyclic guanidine, 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine (hppH), is reported, revealing a hydrogen bridged dimer with extensive delocalisation throughout the ligand framework. Coordination of hppH to lithium chloride afforded the dimeric bis-ligand complex [LiCl(hppH)₂]₂ (4) in which each hppH molecule interacts with a different chlorine atom of the central ‘Li₂Cl₂’ core of the molecule via NH⋯Cl hydrogen bonding. In contrast the 2 ∶ 1 ligand to metal complex is formed with silver(I) chloride to afford AgCl(hppH)₂ (5), a unique example of a monomeric, three-coordinate silver chloride supported by nitrogen-based ligands. The series of mixed ligand complexes [CuX(hppH)(PPh₃)]_n (6, X = Cl, n = 1; 7, X = Br, n = 2; 8 X = I, n = 2) have also been synthesised and structurally characterised, allowing comparisons of the relative coordinating behaviour of hppH and PPh₃ as neutral donors at copper(I) centres to be made.

A sulfonamide 1-tosyl-1-H-benzo(d)imidazol-2-amine (TBZA) and three new complexes of Co(II), Cu(II), and Zn(II) have been synthesized. The compounds have been characterized by elemental analyses, FTIR, ¹H, and ¹³C-NMR spectroscopy. The structure of the TBZA, and its Co(II) and Cu(II) complexes, was determined by X-ray diffraction methods. TBZA and its Co(II) complex crystallize in the triclinic P-1 space group, while the Cu(II) complex crystallizes in the monoclinic P2₁/c space group. Antifungal activity was screened against eight pathogenic yeasts: Candida albicans (DMic 972576), Candida krusei (DMic 951705), Candida glabrata (DMic 982882), Candida tropicalis (DMic 982884), Candida dubliniensis (DMic 93695), Candida guilliermondii (DMic 021150), Cryptococcus neoformans (ATCC 24067), and Cryptococcus gattii (ATCC MYA-4561). Results on the inhibition of various human (h) CAs, hCA I, II, IV, VII, IX, and XII, and pathogenic beta and gamma CAs are also reported.