Structure activity relationship studies of 3-arylsulfonyl-pyrido[1,2-a]pyrimidin-4-imines as potent 5-HT6 antagonists

Silver‐Catalyzed Direct Regioselective C3 Phosphonation of 4H‐pyrido[1,2‐a]pyrimidin‐4‐ones With H‐phosphites

“…The 4 H ‐pyrido[1,2‐ a ]pyrimidin‐4‐ones are important nitrogen‐containing heterocycles and exhibit a wide range of remarkable biological properties (Figure 1), such as 5‐HT 6 antagonist, [9] anti‐cancer, [10] and antioxidant [11] . Among them, paliperidone as classics in chemical neuroscience is used for treatment of schizophrenia [12] .…”

α(β)-Sulfonyl(phosphoryl)acrylonitriles and enamines in the synthesis of biologically active heterocycles

“…У наступній роботі авторам вдалося синтезувати велику серію похідних на основі структури 47, із яких найменшу інгібуючу концентрацію по відношенню до 5-HT 6 -рецепторів мала сполука 47a (рис. 1) [21]. Гетероциклізація при взаємодії 3-диметиламіно-2-сульфонілакрилонітрилу 32 з гуанідином 48 перебігала з утворенням 2,4-діаміно-5-сульфонілпіримідину 49 (схема 16) [15].…”

Metal free C-3 chalcogenation (sulfenylation and selenylation) of 4H-pyrido[1,2-a]pyrimidin-4-ones

“…Interestingly, consistent with our previous observation (Table 1; entry 5), using of 50 mol% of iodine also afforded the 92% yield of thiolated derivative 2a (Table 1; entry 17). Other solvents were inefficient to provide decent yields (Table 1; entries [18][19][20][21][22]. So it is evident from the optimization table that a combination of 50 mol% of iodine and K 2 S 2 O 8 (2 equiv.)…”

“… 14 In this family, 4 H -pyrido[1,2- a ]pyrimidin-4-one ( Fig. 1 ) exhibits versatile biological activities, 15 such as CXCR3 antagonism, 16 HLE inhibition, 17 MexAB-OprM specific efflux pump inhibition, 18 potent 5-HT6 antagonists, 19 and acetylcholinesterase inhibition. 20 Meanwhile, Pd catalyzed direct arylation and alkenylation of 4 H -pyrido[1,2- a ]pyrimidin-4-one through C–H bond functionalization has already been reported in the literature.…”