3,4-dihydropyrimidine-2 (1H) -thiones are compounds widely explored by LaSOM and in this article, they are in the spotlight: N1-substituted dihydropyrimidinones with ortho-substituted aromatic rings exhibit atropisomerism. This variation of stereoisomerism is characterized by the impediment of rotation around a given bond present in the molecule, giving two atropisomers that can be isolated or simply detected. To study the case, we used analytical techniques of Nuclear Magnetic Resonance (NMR) and High Performance Liquid Chromatography (HPLC), moreover theoretical studies in silico were applied to understand the phenomenon. The data obtained indicates the occurrence of these phenomena, which are discussed according to obtaining the molecules (reaction medium, temperature and exposure to microwaves) as well as the analysis of the structure of the N1 substituent. You can find the link to access the article here . Nice reading!