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A series of 2-(hydrazinocarbonyl)-3-aryl-1H-indole-5-sulfonamides possessing various 2-, 3- or 4- substituted phenyl groups with methyl-, halogeno- and methoxy-functionalities, or a perfluorophenyl moiety, has been derivatized by reaction with 2,4,6-trimethylpyrylium perchlorate. The new sulfonamides were evaluated as inhibitors of four mammalian carbonic anhydrase (CA, EC 4.2.1.1) isoforms, that is, CA I, II (cytosolic), CA IX and XII (transmembrane, tumor-associated forms). Excellent inhibitory activity was observed against hCA IX with most of these sulfonamides, and against hCA XII with some of the new compounds. These compounds were generally less effective inhibitors of hCA II. Being membrane impermeant, these positively-charged sulfonamides are interesting candidates for targeting the tumor-associated CA IX and XII, as possible diagnostic tools or therapeutic agents. (C) 2009 Elsevier Ltd. All rights reserved.

Single wall nanotubes are generated by modifying a cylindrical square tiled lattice, in a manner similar to that used previously by us in generating polyhex tori. This way of building enables the orientation of their bonds, resulting a large variety of tubes: crenellated (i.e., armchair, or anthracenoid), zigzag (or phenanthrenoid) non-chiral objects as well as variously twisted (i.e., chiral) tubes. Their energetic stability was evaluated by MM+ calculation. Twisting appears to relax the total energy/atom, which, in large diameter tubes, approaches that in the graphite sheet. Spectral analysis envisages a pallet of shells ranging from the closed to open and metallic ones. This behavior is rationalized in terms of the pattern square net dimensions. Topological characterization includes the Wiener index (i.e., the sum of all distances in a graph ) and the spiral code.

By selecting 5 or 6 parameters from the 14 possible topological parameters referring to the disposition of the 5- and 6-membered rings around each edge in a proper fullerene with isolated pentagons, it is possible to obtain good correlations with calculated (MM+) energies of fullerenes. The correlations were tested on all isomers of IPR fullerenes with 94 to 100 carbon atoms, and standard deviations around 2.5 kcal/mol were obtained.