Fragmentation of doubly charged biomolecules, uracil and amino acids, has been investigated using different ab inito Molecular Dynamics Methods. Time-Dependent Density Functional Theory Molecular Dynamics give a description of the non-adiabatic effects, the charge redistributions that occur in the first few femtoseconds and reveal the importance of the chemical environment. The combination of different techniques allow us to interpret the complex multicoincident spectra obtained experimentally when the molecules collides with ions or are excited with synchrotron radiation.