The abilities of various mono and dimethyl derivatives of benzo(a)pyrene (BP) to initiate skin tumors in mice were determined by using a two-stage system of tumorigenesis. 11-Methylbenzo(a)pyrene was found to be approximately 3 times more active as a tumor initiator than was the parent hydrocarbon; 1-methyl benzo(a)pyrene was about twice as active as was BP. Substitution of a methyl group in po...

Vilsmeier-Haack reaction of 2,3,3-trimethyl-3H-benzo[g]indole, then aqueous basic work-up, leads to benzo[g]indol-2-ylidene- malondialdehydes. These react with various arylhydrazines and quinolin-2-ylhydrazine to form 3,3-dimethyl-2-(1-aryl-1H-pyrazol-4-yl)- 3H-benzo[g]indoles in good yields.

The triethylamine promoted stepwise 1,3-dipolar cycloaddition reaction of N-phenacylbenzothiazolium bromides with nitroalkenes in ethanol resulted in a mixture of two isomeric tetrahydrobenzo[d]pyrrolo[2,1-b]thiazoles with cis/trans/cis- and all-trans-configurations. More importantly, the corresponding dihydrobenzo[d]pyrrolo[2,1-b]thiazoles can be selectively prepared in refluxing ethanol and t...

The conformation of the N-H bond in the structure of the title compound, C(9)H(10)ClNO, is syn to the meta-methyl group, in contrast to the anti conformation observed with respect to the meta-nitro group in 2-chloro-N-(3-nitro-phen-yl)-acetamide. The asymmetric unit of the title compound contains two mol-ecules. The geometric parameters of the title compound are similar to those of 2-chloro-N-(...

The title compound, C(26)H(18)BrNO(4), features a functionalized chromene. The cyclo-hexene ring adopts a sofa conformation and has the nitro group and the bromo-phenyl ring in an axial position. The ten atoms of the chromene moiety lie close to a common plane (r.m.s. deviation = 0.066 Å). The attached phenyl ring is twisted by 32.89 (10)° from the chromene plane. The crystal packing is stabili...

Taurine (2-aminoethanesulfonic acid) was evaluated as an antimutagen in the Ames Salmonella tester strain assay. Taurine inhibited mutagenesis by doxorubicin (-74%), bleomycin (-55%), mitomycin C (-56%), and 2-aminofluorene (-52%), but not danthrone or benzo(a)pyrene, in strain TA102. In strain TA98, doxorubicin mutagenicity, but not that of 2-aminofluorene or benzo(a)pyrene, was inhibited by t...