Antiarrhythmic activity of 4,6-di(het)aryl-5-nitro-3,4-dihydropyrimidin-(1H)-2-ones and its effects on arterial pressure in rats

Features of the behavior of 5-substituted N(3)-acyl-4,6-diaryl-3,4-dihydropyrimidin-2(1H)-ones under electron ionization

“…The features of the dissociative ionization of their molecular ions, which occurs with ketene elimination from the acyl group, are revealed. The subsequent fragmentation of fragment ions proceeds according to the rules established for pyrimidin-2(1H)-one derivatives.Substituted 3,4-dihydropyrimidin-2(1Н)-ones and their N-acyl derivatives comprise a special structural group of heterocyclic compounds whose functional derivatives exhibit various forms of biological activity, in particular, antiviral, antitumoral, antibacterial, antifungal activities, and are modulators of calcium channels and antagonists of adrenergicOne of the most popular physical methods to study organic compounds is mass spectrometry that can be applied not only in analytical, but also structural studies to confirm the structure of biologically active compounds, including hydrogenated pyrimidines [9, 10].We have recently synthesized a series of 4,6-diaryl-3,4-dihydropyrimidin-2(1Н)-ones with a nitro group in position 5 of heterocycle (I), which exhibited high antiarrhythmic activity [11], and also a series of N(3)-acyl derivatives of 5-R 2 -4,6-diaryl-3,4-dihydropyrimidin-2(1Н)-ones (R 2 : NO 2 , COOC 2 H 5 , OPh) [12] as potentially biologically active compounds.The fragmentation main ways of molecules under electron ionization have previously been determined for 5-carbonyl substituted 4-aryl-6-methyldihydropyrimidinones [13][14][15][16][17]. Some rules of the decomposition were also found for 5-R 2 -4,6-diaryl-3,4-dihydropyrimidin-2(1Н)-ones (R 2 : OCH 3 , OAr, SPh, NHCOCH 3 ) [18].…”

“…We have recently synthesized a series of 4,6-diaryl-3,4-dihydropyrimidin-2(1Н)-ones with a nitro group in position 5 of heterocycle (I), which exhibited high antiarrhythmic activity [11], and also a series of N(3)-acyl derivatives of 5-R 2 -4,6-diaryl-3,4-dihydropyrimidin-2(1Н)-ones (R 2 : NO 2 , COOC 2 H 5 , OPh) [12] as potentially biologically active compounds.…”

Selective acylation of 5-nitro- and 5-ethoxycarbonyl-4,6-diaryl-3,4-dihydropyrimidin-2(1H)-ones

“…It was shown by an example of some 5-substituted (COOAlk, COAlk) dihydropyrimidinones that the regioselectivity of the acylation depends both on the character of the acylating agent and of the substituents in the heterocycle [7]. As a rule the reaction occurs at the more nucleophilic atom N 3 at heating the initial neutral compound with the acylating agent or by treating with the agent the corresponding anion [8][9][10].We formerly obtained a series of 4,6-diaryl-3,4-dihydropyrimidin-2(1Н)-ones containing a nitro group in the position 5 of heterocycle I that showed a high antiarrhythmic action [11,12]. In extension of this research we investigated the effect of structural factors in the dihydropyrimidinones on the direction of the acylation and formylation.…”

Three-component condensation of α-nitroacetophenone, aromatic aldehydes, and methylurea

“…1H ) one(4). A mixture of α nitroacetophenone (1.5 g, 9 mmol), 3 nitrobenzaldehyde (1) (1.1 g, 7 mmol), and methylurea (1.0 g, 13.5 mmol) in ethanol (10 mL) containing concentrated HCl (1 mL) was refluxed for 15 h and kept at 20 °C for 10 days.…”