Search

4-[bis(2-chloroethyl)amino]benzaldehyde-N(4)-phenyl-thiosemicarbazone (1), 4-[bis(2-chloroethyl)amino]benzaldehyde-N(4)-para-chloro-phenyl-thiosemicarbazone (2), 4-[bis(2-chloroethyl)amino]benzaldehyde-N(4)-methyl-thiosemicarbazone (3) and 4-[bis(2-chloroethyl)amino]benzaldehyde-benzoylhydrazone (4) were obtained by functionalization of the bis(2-chloroethyl)amino DNA alkylating group with a thiosemicarbazone/hydrazone moiety. The compounds were fully characterized by means of their infrared (including theoretical vibrational analyses) and NMR spectra, as well as by means of X-ray crystal structure determinations. When assayed on a panel of different tumor cells only (1) exhibited cytotoxic effects on B16F10 melanoma cells (IC50 = 17.1 ± 3.1 μM). A cell viability assay on melanoma cells revealed that while (1) had cytotoxic effects on B16F10 and A2058 cells, the structure-related hydrazone (4) was devoid of activity. In addition, (1) was capable to reduce viability of melanoma cells without affecting the viability of non-malignant human endothelial cells (HUVEC), suggesting that this compound or its analogues could be further investigated as potential antimelanoma drug candidates. Preliminary investigation on the mode of action of (1) indicated that the compound induces cell death by necrosis. Theoretical calculations showed that in all compounds (1–4) the reactivities of the N-mustard pharmacophoric group towards dehalogenation are similar. In addition, theoretical studies suggested that the nucleophilicities of the mustard group are very similar in (1–4). Hence, all compounds (1–4) might be expected to exhibit comparable reactivity, and the differences in biological activity among the compounds may not be attributed to variances in reactivity at the N-mustard group.

Herein we describe the syntheses of 4-(2-nitrophenylsulfonamido)benzoic acid (HL), and its tri-n-butyltin(IV) complex, Bu3SnL. The compounds were characterized by elemental analyses, FT-IR, 1H NMR, 13C{1H} NMR and X-ray diffraction. For the complex 119Sn{1H} NMR and 119Sn Mossbauer spectroscopies were also employed. The Bu3SnL is a monomer in the solid and solution states but exists as a polymer in the crystalline structure. The complex adopted distinct geometries, being tetrahedral in solution and intermediate between tetrahedral and trigonal bipyramidal in the solid state. Crystal structure determination of Bu3SnL revealed a bipyramid-trigonal geometry around the metal center, and the presence of a polymeric structure sustained by carboxylate bridges. Interconnections in the crystal structures were analyzed using Hirshfeld surfaces. The 2D-fingerprint plots indicated that the O H/H O interactions are more frequent in the HL·H2O crystal packing (44.9%) than in the Bu3SnL (26.8%).

This is a review article on non-radioactive gallium(III) complexes as new promising metal-based drug candidates. A great variety of gallium(III) complexes and their pharmacological applications as anticancer and antimicrobial agents are described together with possible biological targets and modes of action.

Salicylaldehyde 2-chlorobenzoyl hydrazone (H 2LASSBio-466), salicylaldehyde 4-chlorobenzoyl hydrazone (H 2LASSBio-1064) and their complexes [Zn(LASSBio- 466)H 2O] 2 (1) and [Zn(HLASSBio-1064)Cl] 2 (2) were evaluated in animal models of peripheral and central nociception, and acute inflammation. All studied compounds significantly inhibited acetic acid-induced writhing response. Upon coordination the antinociceptive activity was favored in the complex 1. H 2LASSBio-466 inhibited only the first phase of the formalin test, while 1 was active in the second phase, like indomethacin, indicating its ability to inhibit nociception associated with the inflammatory response. Hence coordination to zinc(II) altered the pharmacological profile of H 2LASSBio-466. H2LASSBio-1064 inhibited both phases but this effect was not improved by coordination. The studied compounds did not increase the latency of response in the hot plate model, indicating their lack of central anti-nociceptive activity. All compounds showed levels of inhibition of zymosan-induced peritonitis comparable or superior to indomethacin, indicating an expressive anti-inflammatory profile., Facultad de Ciencias Exactas

[(n-Bu)Sn(2Ac4oClPh)Cl2] (1), [(n-Bu)Sn(2Ac4oFPh)Cl2] (2), [(n-Bu)Sn(2Ac4oNO2Ph)Cl2] (3), [(n-Bu)Sn(2Bz4oClPh)Cl2] (4), [(n-Bu)Sn(2Bz4oFPh)Cl2] (5) and [(n-Bu)Sn(2Bz4oNO2Ph)Cl2] (6) were obtained by reacting [(n-Bu)SnCl3] with 2-acetylpyridine-N4-orthochlorophenyl thiosemicarbazone (H2Ac4oClPh), 2-acetylpyridine-N4-orthofluorphenyl thiosemicarbazone (H2Ac4oFPh), 2-acetylpyridine-N4-orthonitrophenyl thiosemicarbazone (H2Ac4oNO2Ph), and with the corresponding 2-benzoylpyridine-derived thiosemicarbazones (H2Bz4oClPh, H2ABz4oFPh and H2Bz4oNO2Ph). The antifungal activity of the studied compounds was evaluated against several Candida species. Upon coordination of H2Bz4oNO2Ph to tin in complex (6) the antifungal activity increased three times against Candida albicans and Candida krusei and six times against Candida glabrata and Candida parapsilosis. The minimum inhibitory concentration (MIC) values of H2Ac4oNO2Ph and its complex (3) against C. albicans, C. parapsilosis and C. glabrata are similar to that of fluconazole. All studied compounds were more active than fluconazole against C. krusei.

Metal complexes with 2-acetylpyridine-N(4)-orthochlorophenylthiosemicarbazone (H2Ac4oClPh) were assayed for their cytotoxicity against MCF-7 breast adenocarcinoma and HT-29 colon carcinoma cells. The thiosemicarbazone and most of the complexes were highly cytotoxic. H2Ac4oClPh and its gallium(III) and tin(IV) complexes did not show any inhibitory activity against thioredoxin reductase (TrxR) and glutathione reductase (GR). The palladium(II), platinum(II) and bismuth(III) complexes inhibited TrxR at micromolar concentrations but not GR. The antimony(III) and gold(III) complexes strongly inhibited TrxR at submicromolar doses with GR inhibition at higher concentrations. The selectivity of these complexes for TrxR suggests metal binding to a selenol residue in the active site of the enzyme. TrxR inhibition is likely a contributing factor to the mode of action of the gold and antimony derivatives.

2-Acetylpyridine-phenylhydrazone (H2AcPh), its para-chlorophenylhydrazone (H2AcpClPh) and para-nitrophenylhydrazone (H2AcpNO2Ph) analogues, the corresponding 2-benzoylpyridine-derived hydrazones (H2BzPh, H2BzpClPh and H2BzpNO2Ph) and their gallium(III) complexes were assayed for their cytotoxic activity against U87 (expressing wild-type p53 protein) and T98 (expressing mutant p53 protein) glioma cells. IC50 values against both glioma cells and against the MRC5 (human fetal lung fibroblast) lineage were obtained for the hydrazones, but not for their gallium(III) complexes, due to their low solubility. Hydrazones were highly cytotoxic at nanomolar doses against U87 and T98 cells. The therapeutic indexes (TI = IC50MRC5/IC50glioma) were 2-660 for T98 cells and 28-5000 for U87 cells, indicating that the studied hydrazones could be good antitumor drug candidates to treat brain tumors.