Nickel(II) 2,6-diacetylpyridine bis(isonicotinoylhydrazonate) and bis(benzoylhydrazonate) complexes: structure and antimycobacterial evaluation. Part XI.
The reaction of 2,6-diacetylpyridine (dap) and isonicotinoyl- or benzoylhydrazide leads to bishydrazones H(2)dapin (1a) and H(2)dapb (1b), respectively. The condensation can either take place as a bimolecular kinetic process between the two reactants or as a monomolecular metal-templated synthesis in the presence of nickel(II) ions. In the latter case the reaction products are charged 2,6-diacetylpyridine bis(hydrazone) nickel(II) complexes, which can be easily deprotonated to neutral hydrazonates. Diffractometric analysis of one of these [Ni(dapb)](2) (8b) has shown a binuclear structure with two octahedral nickel(II) ions bridged by two helicoidal dap (bishydrazonates) in a spheroidal structure of C(2V) symmetry. The synthesized complexes 8 are promising as antimycobacterial agents against M. tuberculosis H37Rv. In particular, 8b displays significant activity (MIC=0.025 microg/mL) 10-fold higher than rifampin and equal to isoniazid, while its ligand is ineffective. Compound 8b is also capable of reducing HIV-induced cytopathogenic effect in human T(4 )lymphocytes.
Bottari
B
B
Dipartimento Farmaco-chimico, Facoltà di Farmacia, Università di Messina, Italy.
Maccari
R
R
Monforte
F
F
Ottanà
R
R
Vigorita
M G
MG
Bruno
G
G
Nicolò
F
F
Rotondo
A
A
Rotondo
E
E
D000995:Antitubercular Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D005069:Evaluation Studies as Topic; D006834:Hydrazines / Q000737:chemistry / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D009169:Mycobacterium tuberculosis / Q000187:drug effects; D009942:Organometallic Compounds / Q000737:chemistry / Q000494:pharmacology*
D000995:Antitubercular Agents; D006834:Hydrazines; D009942:Organometallic Compounds; C434757:nickel(II)-2,6-diacetylpyridine bis(isonicotinoylhydrazonate)