The title compound, C₁₃H₁₆N₄S (DAMP-DMB), was synthesized through the reaction of 2,4-dimethylbenzyl chloride with diaminopyrimidine-thiol. Single-crystal X-ray diffraction analysis confirmed that the compound crystallizes in the monoclinic crystal system, space group P2₁/c. The asymmetric unit contains a single molecular entity. Structural examination revealed the presence of a dimeric arrangement consolidated by N—H...N hydrogen-bonding interactions. Additionally, Hirshfeld surface analysis indicated that H...H, N...H, C...H, and S...H contacts account for 98.9% of the total intermolecular interactions to the Hirshfeld surface.

Thiopyrimidines represent one of the most active classes of compounds, possessing a wide spectrum of biological activities. Herein, we report the synthesis of 2-(heptylthio)pyrimidine-4,6-diamine (HPDA) via S-alkylation. The structure of HPDA was elucidated using ¹H and ¹³C nuclear magnetic resonance (NMR), heteronuclear multiple bond correlation (HMBC), high resolution mass (HRMS), and infrared (IR) spectroscopies.

2,5-Dimethylbenzyl 2-{(4,6-diaminopyrimidin-2-yl)thio}acetate was prepared by an alkylation reaction between the sodium salt of 4,6-diamino-2-mercaptopyrimidine and chloroacetic acid. The structure was unambiguously elucidated based on high-resolution mass spectrometry (HRMS) as well as spectroscopies such as infrared (IR) and nuclear magnetic resonance (NMR).

N-alkylacridinium derivatives are some of the most popular azo dye templates. Herein, we report the synthesis of 3-methoxy-5-methyl-12-phenylbenzacridinium iodide (MMPBAI) via N-alkylation. The structure of MMPBAI was elucidated using ¹H Nuclear magnetic resonance (NMR), ¹³C NMR, Electronspray ionization mass spectrometry (ESI-MS), and Fourier-transform infrared spectroscopy (FT-IR). MMPBAI could not visualize double-stranded DNA in agarose gel, although the structural core would still be interesting as a template for new azo dyes.

The synthesis, crystal structure, and Hirshfeld surface analysis of N-(4-methoxyphenyl)picolinamide (MPPA), C₁₃H₁₂N₂O₂, are presented. MPPA crystallizes in the monoclinic space group P2₁/n, with a single molecule in the asymmetric unit. Structural analysis reveals that all non-hydrogen atoms are nearly coplanar, and the molecule exhibits two intramolecular hydrogen bonds that stabilize its conformation. Supramolecular features include significant intermolecular interactions, primarily C—H...π and various hydrogen bonds, contributing to the overall crystal cohesion, as confirmed by energy framework calculations yielding a total interaction energy of −138.3 kJ mol⁻¹. Hirshfeld surface analysis indicates that H...H interactions dominate, followed by C...H and O...H interactions, highlighting the role of van der Waals forces and hydrogen bonding in crystal packing.