The 3,5-disubstituted tetrahydro-2H-1,3,5-thiadiazine-2-thione scaffold has found many applications in recent years. This review is aimed at highlighting the most important aspects of these compounds: Synthesis, spectroscopic characterization and biological activities. How the chemical nature of N-substituents influences the overall activity and cytotoxicity profile will also be discussed.

A green approach for the synthesis of a set of ten 4-aryl substituted-5-alcoxy carbonyl-6-methyl-3,4-dihydro-2(1H)-pyridones using Meldrum’s acid has been devised, the absence of solvent and the activation with infrared irradiation in addition to a multicomponent protocol are the main reaction conditions. The transformations proceeded with moderated yields (50–75%) with a reasonable reaction rate (3 h). It is worth noting that two novel molecules of the new class of the bis-3,4-dihydropyridones were also obtained. In addition, a comparison without the use of infrared irradiation was performed.

Structural and conformational study of a new steroid derivative using X-ray and density functional calculations.

A new series of 1,4-dihydropyridines (1,4-DHPs) endowed with ester groups bearing long and functionalised alkoxy chains at the C3 and C5 positions of the nitrogen ring have been prepared from the corresponding β-keto esters which were in turn prepared by a lipase catalysed transesterification reaction. The structural study has been carried out by X-ray crystallography and theoretical calculations at the semiempirical (AM1), ab initio (HF/6-31G*) and B3LYP/6-31G* levels and reveals that the long alkyl chains do not have any influence on the required geometry of the 1,4-DHPs for biological activity. However, these chains have a strong impact on the lipophilicity and, therefore, they could be used to gain a better control of the duration of the pharmacological action.