The electronic structures and atomic interaction parameters of a series of nonchiral (n,n) and (n,0) nanotubes, as well as fullerene-like molecules based on isoelectronic TiO2 and ZrS2, are predicted by quantum-chemical methods. These characteristics are studied as a function of the type of atomic configuration, size, and chemical composition of nanostructures. The results are compared to the electronic properties of crystalline titanium dioxide and zirconium disulfide.