Three amine-modified Merrifield resins (AMMRs) were synthesized with ethane diamine, methylamine and dimethylamine to assess the impact of amine group on SO2 adsorption under low SO2 concentration. The dimethylamine-modified Merrifield resin (DMAMR) grafting with tertiary amine groups showed the...

We report herein an efficient synthesis of 2-substituted furo[3,2-b]pyridines and their biological evaluation as melatonin receptors ligands. The proposed eight-step sequence ending with a Suzuki coupling allowed a rapid access to various analogues. The steric hindrance and the conformation of t...

1,3-Bis(3-ammonium-propyl)tetramethyldisiloxane sulfate resulted from the reaction between 1,3-bis(3-aminopropyl)tetramethyldisiloxane with a proper transition metal (iron(III) or vanadium(IV) oxide) salt as anion generator and a carbonylic compound (4-imidazole carboxaldehyde or 2-hydroxybenzal...

Having in mind the synthesis of a cooper complex with the product of condensation between an anhydride and a siloxane diamine as a new polydentate ligand, 2,3-pyridinedicarboxylic anhydride (PDCA) was treated first with 1,3-bis(3-aminopropyl)tetramethyldisiloxane (AP0) and then with cooper chlor...

We describe a practical and elegant method of constructing a thiazine ring fused with benzene under mild reaction conditions. A variety of 4-iodo-2H-benzo[e][1,2]thiazine-1,1-dioxides were prepared with high regioselectivity via a two-step process involving Pd/C-mediated C–C coupling of o-halob...

Acridine thiosemicarbazones 3a–g, obtained through a two-step reaction between aromatic isothiocyanates and hydrazine followed by the treatment with acridin-9-carbaldehyde, in reaction with bifunctional reagents; methyl bromoacetate (MBA) and diethyl acetylenedicarboxylate (DEAD) afforded acrid...

A continuous flow process is presented that enables the efficient synthesis and derivatization of 1,2,4-thiadiazole heterocycles. Special attention was given to the safe handling of the versatile yet hazardous trichloromethane sulfenylchloride reagent including its in-line quenching in order to ...

A copper-catalyzed N–S bond formation was utilized to produce 3-substituted-5-amino-1,2,4-thiadiazoles from imidoyl thioureas obtained by reaction of amidine hydrochlorides with isothiocyanates. Moreover, the 1,2,4-thiadiazoles were generated through a one-pot protocol without the isolation of ...

We report the results of a computational study of the possible metabolites of 4-aminoazobenzene (AAB) and its monomethoxy derivatives using density functional theory (DFT) and the semiempirical AM1 method. These calculations identify several factors that may influence the radically different car...

Formation of hepatic DNA adducts was studied in rats following intraperitoneal administration of a hepatocarcinogen, 3-methoxy-4-aminoazobenzene (3-MeO-AAB) and a non-hepatocarcinogen, 2-methoxy-4-aminoazobenzene (2-MeO-AAB). The 32P-post-labeling assay revealed 3-MeO-AAB to give more than 20-fo...

A new P450 responsible for mutagenic activation of 3-methoxy-4-aminoazobenzene (3-MeO-AAB) which is a potent procarcinogen was purified from renal microsomes of male mice using an index of umu gene expression. The purified P450 had high bioactivation toward 3-MeO-AAB and also 2-aminofluorene and...

Treatment of Splague Dawley rats with 3-methoxy-4-aminoazobenzene (3-MeO-AAB) resulted in striking increase of the activity of hepatic microsomal cytochrome P-450s which could efficiently catalyze the mutagenic activation of hepatocarcinogenic aromatic amines such as a tryptophan-pyrolysate comp...

SummaryRenal microsomes from male mice (BALB/c, DBA/2 and BALB/c × DBA/2 F1) showed about 10-fold greater activity for mediating mutagenic activation of 3-methoxy-4-aminoazobenzene (3-MeO-AAB) toward Salmonella typhimurium TA98 than did the corresponding hepatic microsomes, as compared on the b...

Rat liver microsomal enzyme(s) that catalyze mutagenic activation of a carcinogenic aminoazo dye, 3-methoxy-4-aminoazobenzene (3-MeO-AAB), was studied by virtue of the Salmonella typhimurium TA98 assay using o-aminoazotoluene (OAT) as the control. Male Wistar rats were pretreated with phenobarbi...

Activities of the renal and hepatic microsomal enzymes responsible for the N-hydroxylation and mutagenic activation of 3-methoxy-4-aminoazobenzene (3-MeO-AAB) were examined in male mice, rats, hamsters and guinea pigs. In all these rodent species, hepatic microsomes showed definite N-hydroxylati...

Optimised geometrical structural parameters, harmonic vibrational frequencies, natural bonding orbital analysis and frontier molecular orbitals are determined by B3LYP and B3PW91 methods. The exact geometry of 5-chloro-1-methyl-4-nitroimidazole is determined through conformational analysis. The ...

Solubilities of 5-chloro-1-methyl-4-nitroimidazole in eleven organic solvents of methanol, ethanol, isopropanol, n-propanol, N-methyl-2-pyrrolidone, ethyl acetate, toluene, acetone, 2-butanone, trichloromethane and 1,4-dioxane were measured by using an isothermal saturation method at temperature...

A method for the synthesis of (E)-4-(tetrahydropyran-2-yloxy)-3-methylbut-2-enyl bromide is described and its use in the synthesis of [3H]zeatin riboside, zeatin and a xanthine derivative by alkylation is reported.

Recently, the cis-isomer of zeatin riboside (ZR) was reported as a free cytokinin in tobacco shoots as well as in a few other plant extracts. Although the identification was based on physico-chemical methods, the possibility that it was an artefact of extraction procedure used was not excluded. ...

Zeatins, a major type of cytokinin, are ubiquitous in higher plants, and involve in regulating a wide range of developmental processes. The development of highly specific ligands to zeatins would be very useful in plant biological research. Here we describe a group of oligonucleotide ligands (ap...