Benz[c]acridine (B[c]ACR) and 12 of its derivatives, including the 5 metabolically possible trans-dihydrodiols, the diastereomeric bay-region diol-epoxides, 2 non-bay-region diol-epoxides, and the K-region arene oxide, were tested for tumor-initiating activity on mouse skin. A single topical application of 0.4 to 2.5 mumol of compound was followed 12 days later by twice-weekly applications of t...

The reaction of homophthalic anhydride and N-(furan-2-yl-methylidene)- benzylamine in different solvents and varying temperatures was studied in detail. Mixtures of the expected trans- and cis-1,2,3,4-tetrahydroisoquinoline-4-carboxylic acids trans-5 and cis-5, along with by-products 6 and 7 were obtained in dichloroethane or benzene. In pyridine, used for the first time, the reaction became co...

DNA photolyases catalyze the splitting of the cyclobutane ring joining the two dihydropyrimidines of a pyrimidine dimer by a photoinduced electron-transfer reaction. Previous studies concluded that photolyase repairs only the cis-syn form of the eight stereoisomers of the cyclobutane pyrimidine dimer (Pyr[ ]Pyr). In this study we found that Escherichia coli photolyase binds to the trans-syn-I i...

This paper reports on the microstructures formed in aqueous solutions containing mixtures of sodium dodecyl sulfate (SDS) and a photosensitive, bolaform surfactant, bis(trimethylammoniumhexyloxy)azobenzene dibromide (BTHA). By using quasi-elastic light scattering and small-angle neutron scattering, we determined that aqueous solutions containing SDS and the trans isomer of BTHA (0.1 wt % total ...

A computational investigation has been carried out to elucidate the origin of the exclusive exo-selectivity in the Pd-catalyzed cyanoesterification of strained cyclic olefins, norbornene and norbornadiene. A hybrid density functional was selected for the level of theory with a triple-ζ quality basis set, which was proposed in an earlier study to provide an experimentally sound ground state elec...

This study investigated the evolution of trans-9 trans-11 conjugated linoleic acid (CLA) from cis-9 trans-11 CLA during methylation and its avoidance through a rapid base methylation of milk fat. The study examined three conditions shown to result in loss of cis-9 trans-11 CLA during methylation namely: temperature, methylation time, water contamination in old reagents and acidic conditions. Th...

The solid-state, low-temperature linkage isomerism in a series of five square planar group 10 phosphino nitro complexes have been investigated by a combination of photocrystallographic experiments, Raman spectroscopy and computer modelling. The factors influencing the reversible solid-state interconversion between the nitro and nitrito structural isomers have also been investigated, providing i...

NMR was used to investigate the reaction of cis- and trans-[RuCl(2)(DMSO)(4)] with the antiviral drug acyclovir, a guanine derivative containing the acyclic (2-hydroxo) ethoxymethyl pendant linked to N(9). Studies were performed in aqueous solutions at ambient temperature and at 37 ( degrees )C, and at various molar ratios. Both isomers yielded two compounds, a monoadduct and a bisadduct, the r...