In this study an attempt was made to understand the structural requirements for Topoisomerase I (Topo I) inhibition using a novel Group based QSAR (GQSAR) or fragment based QSAR technique. Here we combined the GQSAR technology with conventional 2D and 3D QSAR to derive GQSAR models for various reported naphthoquinone derivatives. Various regression models such as Multiple Regression (MRA), Part...

The mechanism(s) of toxicity of 1-naphthol and two of its possible metabolites, 1,2- and 1,4-naphthoquinone, to freshly isolated rat hepatocytes has been studied. 1-Naphthol and both naphthoquinones exhibited a dose-dependent toxicity to hepatocytes. [1-14C]-1-Naphthol was metabolised by hepatocytes predominantly to its glucuronic acid and sulphate ester conjugates, but small amounts of covalen...

In an effort to develop new antimalarials, some 1,4 naphthoquinone derivatives were designed on the basis of results of computational studies reported in previous paper, which showed that 2 nd or 3 rd or both position of 1,4 naphthoquinone is most suitable for better antimalarial activity. When the reaction of 1,4 naphthoquinone was performed without a catalyst several secondary products were f...

1-Naphthol has recently been shown to be selectively toxic to short-term organ cultures of human colorectal tumor tissue. The mechanism underlying 1-naphthol’s selective toxicity is as yet unknown, but may be due to the formation of naphthoquinone metabolites, which are known to be highly toxic to tumor cells. By using highperformance liquid chromatography with reductive electrochemical detecti...

Four strains of the fungus Quambalaria cyanescens (Basidiomycota: Microstromatales), were used for the determination of secondary metabolites production and their antimicrobial and biological activities. A new naphthoquinone named quambalarine A, (S)-(+)-3-(5-ethyl-tetrahydrofuran-2-yliden)-5,7,8-trihydroxy-2-oxo-1,4-naphthoquinone (1), together with two known naphthoquinones, 3-hexanoyl-2,5,7,...

A member of the marine streptomycete clade MAR4, Streptomyces sp. CNQ-509, has genetic potential for the biosynthesis of hybrid isoprenoids and produces several meroterpenoids such as naphterpin, nitropyrrolin and marinophenazine. Our research on the strain CNQ-509 led to the isolation of two new naphterpin derivatives (1 and 2) comprised of naphthoquinone and geranyl moieties along with the kn...

The aim of this study was to evaluate the possible effects a 50 Hz electric field on brain tissue and positive juglone (5-hydroxy-1,4-naphthoquinone) antioxidant activity, using immunohistochemical technique male Wistar-Albino rats. blood were also examined biochemical, physiological comet methods. Animals randomly divided into three groups (eight in each group): group I: control, II: field, II...

The synthesis of a naphthoquinone amino acid and its electrochemical characterization in a peptide is presented.

Oximes are known for their anti-inflammatory, antimicrobial, antioxidant, and anticancer activities. Frequently, modification of biologically active carbonyl compounds into oximes leads to increased activity. The present study reports the reactivity 2-alkanoylnaphthohydroquinones against hydroxylamine under aerial conditions. Results show that, depending on structure hydroquinones, reaction pro...

The toxic profile of lawsone (2-hydroxy-[1,4]naphthoquinone) and a series of [1,4]naphthoquinone derivatives was evaluated against the brine shrimp Artemia salina and against the mollusk Biomphalaria glabrata, the main transmitting vector of schistosomiasis in Brazil. Of the seventeen compounds tested nine fell below the threshold of 100 microg/mL set for potential molluscicidal activity by the...