Association of nucleic acids with complexes of N-methyl isatin-β-thiosemicarbazone and copper

The Thiosemicarbazones

“…They concluded that direct interaction between IBT and DNA was not likely to be the primary mode of action ofthis agent. As shown later in this section, IBT in the presence of divalent copper can change the physical configuration of DNA (MIKELENS et al 1976). Furthermore, later work would confirm a slight change in the adsorption spectrum of DNA (PILLA!…”

“…The same binding experiments were carried out with the isoquinoline-and pyridine-TSCs, but no good correlation was found. Although 2-formylpyridine-TSC had the most antiviral activity and complexed well with DNA in the presence of CUS04, the other TSCs of 5-hydroxy-2-formylpyridine and I-formylisoquinoline having moderate antiviral activity hardly complexed at all with DNA MIKELENS et al 1976). One could speculate that other metals are involved in the action of these compounds (LEVINSON et al 1977 b).…”

“…No indication of this was found in treated or untreated cells. Another possibility was that the drug-copper complex became bound to DNA and these proteins were induced as a result.This hypothesis was based on their previous observations (MIKELENS et al 1976) that drug-copper complexes, but not drug alone, were bound to DNA and RNA in vitro. Indeed, LEVINSON et al (1979) found that a number of che1ating agents including l-formylisoquinoline-TSC (Sects.…”

Complexation of trace metals in natural waters

“…Copper complexes are known (Mikelens et al, 1976;White, 1977) to form intercalative complexes with DNA. It is possible that the large, and unexpected, difference in toxicity between the copper complexes of 2,9-dimethyl-1,10-phenanthroline and 2,9-dimethyl-4,7-diphenyl-1, 10-phenanthroline (Table 4) is due to the inability of the bulkier 4,7-diphenyl derivative to form an intercalative complex.…”

Structure, magnetic properties and nuclease activity of pyridine-2-carbaldehyde thiosemicarbazonecopper(II) complexes

“…The reoxidation of Cu I to Cu II in presence of O 2 provokes the regeneration of the [CuL] + entities in vitro and the simultaneous formation of oxygen active species such as O À 2 , H 2 O 2 and OH Å , which can induce oxidative cleavage in DNA and therein nuclease activity [28][29][30]. The association of the complexes to the nucleic acids can favor the oxidative stress [31,32]. Anyway, difficulties inherent to biochemical studies add up to the complexity of the thisemicarbazonecopper(II) system itself.…”