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A series of bis(amido) complexes of rare earth metals {2-[Ph2P(O)]C6H4NC(tBu)N(2,6-Me2C6H3)}Ln(N(SiMe3)2)2, (Ln = Y (2), Nd (3), La (4)) was synthesized using the amine elimination reaction of Ln[N(SiMe3)2]3 (Ln = Y, Nd, La) and parent amidine 1 in THF, and the products were isolated in 60 (2), 61 (3) and 72% (4) yields, respectively. The X-ray studies revealed that complexes 2–4 are solvent-free and feature intramolecular coordination of the Ph2PO group to the Ln ion. Complexes 2–4 were investigated as precatalysts for isoprene polymerization. The ternary systems 2–4/borate/AlR3 (AlR3 = AliBu3, AliBu2H; borate = [Ph3C][B(C6F5)4], [PhNHMe2][B(C6F5)4]) were found to be active in isoprene polymerization and enable complete conversion of 1000 equivalents of monomer into polymer at 25 °C within 1–24 h affording polyisoprenes with polydispersities Mw/Mn = 1.12–9.46. The effect of the organoaluminium component and [Ln]/[AlR3] ratio on the catalytic activity and selectivity of the ternary catalytic systems was investigated. Complexes 2–4 proved to be efficient catalysts for the ring-opening polymerization of rac-lactide, which allow conversion of up to 500 equivalents of monomer into a polymer at room temperature within 30 min and afford atactic polylactides with high molecular weights and moderate molecular-weight distributions (1.29–2.12). Complexes 2–4 appear to be well-suited for achieving immortal polymerization of lactide, through the introduction of large amounts of isopropanol as a chain-transfer agent.

Purpose and tasks: to establish new prognostic criteria of date of prolongation of pregnancy with premature discharge of amniotic fluid on the basis of performance monitoring of cell immunity of mother in the dynamics of observation and the child at the time of completion childbirth. Material and methods. A clinical and laboratory examination of 50 pregnant women, the pregnancy of women was complicated by premature rupture of membranes at 22-34 weeks of gestation. The control group consisted of 40 women with normal pregnancy with the same time of gestation. The traditional methods of clinical and laboratory examination were used to assess the status of pregnant women. The study of peripheral blood was performed with hematological analyzer BC- 3000+. Subpopulations of peripheral blood lymphocytes was studied by cytometry using monoclonal antibodies (apparatus «FAC SCalibur» company «BectonDickinson», USA). Results. The development of leukocytosis with absolute and relative lymphopenia, reduction of CD16+56+lymphocytes and CD19 B lymphocytes were revealed in pregnant women with premature rupture of membranes. The failure of proliferative activity CD3+4+ T-helper cells, the increase of level of CD3+8+ cytotoxic T lymphocytes were revealed at the time of onset of labor after the prolongation of pregnancy. Prolongation of pregnancy at patients with premature rupture of membranes combined with the development of leukocytosis in the fetus, as well as the mother in the same period of observation. At the same time, unlike the parent organism, activation of B-lymphocyte proliferation and humoral immunity at fetus were occurred.