*3.1. Synthesis and Spectroscopic Properties*

The synthetic routes for compounds **6** and **7** are described in Scheme 2; Scheme 3. Intermediate **2** was synthesized through the nucleophilic substitution of the acrylate group of methyl (*E*)-3-methoxyacrylate by *N*-iodosuccinimide. The formation of intermediate **3** from intermediate **2** and arylboronic acid was achieved via the Suzuki–Miyaura cross-coupling reaction. The synthesis of intermediate **4**, the precursor of compound **6**, was achieved via the reduction of intermediate **4** using Pd(PPh3)<sup>4</sup> as the catalyst under nitrogen atmosphere. Compound **6** was afforded by the condensation of intermediate **4** and fenclorim **5.** Compound **7** was synthesized by a one-step condensation method, using fenclorim and phenylaline as starting materials.

The chemical structures of compound **6** and **7** were characterized by NMR spectroscopy, HRMS, and X-ray diffraction analysis. For compound **6**, signals corresponding to C–H protons in the phenyl ring and pyrimidine were observed at δ 7.21–8.41 and δ 6.61, respectively; signals corresponding to the C–H proton to N–H proton in imino group were observed δ 6.69. For compound **7**, signals corresponding to C–H protons in methoxyl groups were observed at δ 3.54 and δ 3.67, respectively; signals corresponding to the C–H proton to C–H proton in pyrimidine ring were observed at δ 6.63, and signals corresponding to the C–H proton in the phenyl ring were at δ 7.24–8.32. In the compound **6** <sup>13</sup>C-NMR spectra, chemical shifts of carbons that resonated at δ 107.18–170.47 were assigned to carbons in the phenyl ring and pyridine ring. The chemical shifts of carbons that resonated at δ 51.59 and 61.93, respectively, were assigned to the carbons in methoxyl groups. The signal at δ 104.46 can be assigned to carbon (C-7) in the acrylate group. In the <sup>13</sup>C-NMR spectra of compound **7**, chemical shifts linked to aromatic rings (phenyl ring and pyrimidine ring) appeared at 100.5–164.94. All HRMS data for compounds **6** and **7** were well-matched with theoretical values calculated from their chemical formula.
