We present the results of an investigation of sulfur containing compounds using a tight-binding (TB) approach, which is a second-order approximation to density-functional theory (DFT). The performance of the so-called self-consistent charge density-functional based TB (SCC-DFTB) method is analyzed via comparison of the results for several molecular properties with other semi-empirical methods as well as with full DFT calculations. We also examine different conformers of the amino acid cysteine in order to estimate the reliability of our method for large-scale biomolecular systems. We find that SCC-DFTB provides, in general, good agreement with full DFT calculations and a similar deviation from experiment.