The JTVAE was trained and evaluated using MOSES datasets and criteria. The MOSES training dataset yielded a vocabulary set of 533 SMILES strings representing molecular subgraphs. We executed the JTVAE pretraining with a configuration featuring a hidden size of 450 and a latent size of 56, continuing until convergence was achieved. The training process encompassed 16 epochs, during which approximately 400,000 steps of model parameter updates were conducted. All configurations of this pretraining model are detailed in Supplement material. † 2 The evaluation of the pretraining model is summarized in Table .