Гексафторосиликат состава (LH)2SiF6 (I), (L = 4-гидроксиметилпиридин) выделен в качестве продукта взаимодействия метанольного раствора L и 45%-й кремнефтороводородной кислоты (L:H2SiF6 = 1:3). В кристаллической структуре I катионы и анионы объединены Н-связями NH⋯F (N⋯F 2.809(2), 2.824(2) Å) и OH⋯F (O⋯F 2.7036(18) Å), геометрия аниона SiF62– — искаженный октаэдр (расстояния Si—F 1.6780(11)—1.6877(11) Å. В ИК спектре I идентифицированы полосы поглощения основных колебаний, определены растворимость I в воде и ряде органических растворителей, а также степень гидролиза соли в 1⋅10–4 М водном растворе.

We report here the synthesis and our studies of the structure, physicochemical properties, and anticaries activity of a novel potential anticaries substance 2-amino-4,6-dihydroxypyrimidinium hexafluorosilicate. IR spectra, EI mass spectra, and 19F NMR spectra were obtained and their properties were studied. Biological investigations were performed on animals kept on the Stephan caries-inducing diet (50% sucrose). Alkaline phosphatase (AlkP) and acid phosphatatase (AcP) were assayed in pulp homogenates and the AlkP:AcP ratio was used to assess the mineralization index (MI). AlkP activity was measured in serum, along with alanine aminotransferase (ALT). The number and depth of caries lesions to the teeth were assessed and caries prophylactic efficacy (CPE) was computed. The data showed that 2-amino-4,6-dihydroxypyrimidinium hexafluorosilicate decreased the number of caries lesions by 45.5% and had high anticaries efficacy, five times greater than that of sodium fluoride.