Features removed (strings):
_raw_Reaction number
_raw_name
_raw_SMILES
_raw_SMILES.nosalt  (keep in the first round in order to filter by amine)
_rxn_Synthesis_Method
_raw_Types
_raw_Notes


Features removed (missing too many values):
_feat_isoelectric	
_feat_apKa1	
_feat_apKa2
_feat_bpKa3	
_feat_bpKa4
_feat_bpKa2: feature kept, -1 used as missing value indicator

Features removed (misleading / not used):
_out_Purity

Feature modified:
_out_Bool4Outcome is the original _out_Outcome but where it is TRUE if outcome was 4 and FALSE otherwise
