As a de novo design tool we use REINVENT, which is an open-source program . REINVENT uses a deep generative model to generate small molecules 𝑚 in the SMILES format. The generative model is used in a reinforcement learning scenario where the main objective is to maximize the score of a composite scoring function. REINVENT generates molecules by sequentially adding tokens representing atoms to a SMILES string using the generative model, also referred to as 'agent' later in the text. In reinforcement learning mode, a batch of generated SMILES strings at each epoch are scored using the scoring function. The score is used as a reward to tune the weights of the agent and thus train it to produce more high-scoring molecules.