The slow evaporation reaction of 2-amino-4-methylpyrimidine and transition metal cation (M^II = Fe and Ni) in the presence of sulfuric acid H₂SO₄ affords two novel double sulfate salts with similar general formula (C₅H₈N₃)₂[M^II(H₂O)₆](SO₄)₂·2H₂O (M^II = Fe and Ni) abbreviated FePRM and NiPRM, respectively. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by Infra-Red (IR) spectra, thermogravimetric analysis—differential scanning calorimetry (TG-DSC) and variable temperature powder X-ray diffraction (VT-PXRD) measurements. Structural characterization shows that the interplay of N–H···O, O–H···O and π···π interactions between lattice and coordinated water and ligands significantly contribute to the crystal packing leading to the formation and strengthening of three dimensional supramolecular assembly. Then, the structure exhibits lamellar topology where the interlayer distances are 13.065(4) and 13.138 (5) Å for FePRM and NiPRM, respectively. Hirshfeld surface analysis employing 3D molecular surface contours and 2D fingerprint plots have been used to analyze the intermolecular interactions present in the crystals. The optical properties were characterized by UV–visible spectroscopy and the calculated band gap was estimated to be 3.91 and 4.08 eV for FePRM and NiPRM, respectively. In addition, the biological activities of the complexes were investigated through the scavenging effect on DPPH radicals, reducing and phosphonolybdonum assay as antioxidant activities.

2-氨基-4-甲基嘧啶和过渡金属阳离子（M ^II  = Fe和Ni）在硫酸H ₂ SO ₄的存在下的缓慢蒸发反应产生了两种具有相似通式（C ₅ H ₈ N）的新型双硫酸盐₃）₂ [M ^II（H ₂ O）₆ ]（SO ₄）₂ ·2H ₂ O（M ^II  = Fe和Ni）缩写为FePRM和NiPRM， 分别。它们的结构已通过单晶X射线衍射分析确定，并进一步通过红外（IR）光谱，热重分析-差示扫描量热法（TG-DSC）和可变温度粉末X射线衍射（VT-PXRD）进行了表征。测量。结构表征表明，晶格与配位水和配体之间的N–H···O，OH–·H··O和π···π相互作用显着促进了晶体堆积，从而形成了三者尺寸超分子组装。然后，该结构呈现出层状拓扑，其中FePRM和NiPRM的层间距离分别为13.065（4）和13.138（5）Å。使用3D分子表面轮廓和2D指纹图谱的Hirshfeld表面分析已用于分析晶体中存在的分子间相互作用。光学性质通过紫外可见光谱表征，FePRM和NiPRM的计算带隙分别估计为3.91和4.08 eV。此外，还通过清除DPPH自由基，还原和磷钼矿法作为抗氧化剂活性，研究了复合物的生物活性。