Synthesis, structure, and optical properties of 3-(1H-1,2,3-triazol-1-yl)-substituted 4H-pyrido[1,2–a]pyrimidin-4-ones and 4H-quinolizin-4-onesHumar, Tadej (Avtor) Ciber, Luka (Avtor) Grošelj, Uroš (Avtor) Petek, Nejc (Avtor) Štefane, Bogdan (Avtor) Svete, Jurij (Avtor) quinolizinesazaquinolizinesalkynescopper-catalyzed azide-alkyne cycloadditionsbioconjugationfluorescent labellingCopper-catalyzed cycloadditions of terminal alkynes to 3-azido-4H-pyrido[1,2–a]pyrimidin-4-one and 3-azido-1-cyano-4H-quinolizin-4-one, prepared in four steps from methyl 2-benzoylamino-3-(dimethylamino)propenoate, yielded the corresponding 3-(1H-1,2,3-triazol-1-yl)-substituted 4H-pyrido[1,2–a]pyrimidin-4-ones and 4H-quinolizin-4-ones in 44–90 % isolated yields. The structures of the cycloadducts were determined by $^1$H NMR, $^{13}$C NMR, and 2D NMR techniques (COSY, HSQC, HMBC). The optical properties of the luminescent intermediates and final products were determined. In methanol, the compounds showed absorption at 350–400 nm, emission at 411–526 nm, and quantum yields of ∼5 × 10$^{−2}$. Optical properties depended on the heterocyclic core (pyrido[1,2–a]pyrimidinone or quinolizinone), while the effect of substituents on optical properties was weak.20262025-12-01 12:27:58Članek v reviji176451UDK: 547.83ISSN pri članku: 0143-7208DOI: 10.1016/j.dyepig.2025.113434COBISS_ID: 259137283sl