Machine translation finds use in cheminformatics in “translation" from one language (e.g. reactants) to another (e.g. products). The variational Auto-encoder (VAE) is another widely adopted text generation architecture BIBREF101. Generative Adversarial Network (GAN) models generate novel molecules by using two components: the generator network generates novel molecules, and the discriminator network aims to distinguish between the generated molecules and real molecules BIBREF107. 
 Question: Are this models usually semi/supervised or unsupervised?
Both supervised and unsupervised, depending on the task that needs to be solved.