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Chirality has an important role in the drug design because enantiomers may exhibit different bioactivity when interacting with macromolecules of a living organism. In our previous work, based on the analysis of a set of 100 chiral drugs, a relationship was established between the sign of chirality of enantiomers and their bioactivity. To understand the reasons for the observed patterns of chiral specificity of drug enantiomers, the interaction of 10 enantiomeric pairs of chiral drugs with the corresponding target proteins has been considered using molecular docking and further postprocessing by quantum chemistry methods. The data obtained confirm that the energetic aspect of the interaction between opposite enantiomers and target protein affects the enantiomer biological activity. In addition, the results show that molecular docking is able to distinguish between bioactive and inactive/less active enantiomers, although many docking programs are not accurate enough to distinguish a weak inhibitor from a strong one. [ABSTRACT FROM AUTHOR]

Perovskite LaNiO3 is of immense significance in a range of fields such as heterogeneous catalysis. Herein, new convenient approach for preparing LaNiO3via thermolysis of new simple complexes, [Ni (bpy)3] [La (NO3)5(MeCN)] (1, bpy is 2,2'‐bipyridine) and [Ni (phen)3] [La (NO3)5(H2O)]·2MeCN (2, phen is 1,10‐phenanthroline), is reported. These first examples of unambiguously characterized LaNiO3 precursors are chemically stable and can be synthesized rapidly in good yields. While virtually monophasic LaNiO3 can be prepared from 2via only 3‐h annealing on air at 800°C, there are always minor admixtures in oxide samples prepared from 1. Peculiarities of intrinsic thermal transformations of 1 and 2 affecting such difference have been revealed. Thus, 1 and 2 are the first series of compositionally related heterometallic La‐Ni complexes studied as precursors for LaNiO3‐based ceramics. Comparatively high surface areas of LaNiO3‐based ceramics produced from 1 and 2 at 800°C determine its high catalytic activity towards dry reforming of methane (DRM) to syngas. Nearly quantitative CH4 and CO2 conversions as well as CO and H2 yields were achieved in 800–900°C range without preliminary reduction to Ni/La2O3 composites. Thus, LaNiO3‐based ceramics prepared from 1 and 2 are good precursors for in situ production of efficient catalysts for DRM. [ABSTRACT FROM AUTHOR]

Carboxycymantrene CymCOOH (Cym = (η5‐C5H4)Mn (CO)3) was applied to assemble a series of uncommon Cd‐Mn carboxylate complexes comprising 1D‐polynuclear [Cd (OOCCym)(acac)]n (1) as well as oligonuclear species, [Cd2(OOCCym)4(EtOH)4)] (2), [Cd (OOCCym)2(bpy)(H2O] (3, bpy = 2,2′‐bipyridine) and [Cd (OOCCym)2(phen)2]·EtOH (4, phen = 1,10‐phenantroline). Compound 2 was found to be a product of irreversible SCSC transition from [Cd2(OOCCym)4(EtOH)3(H2O)]·EtOH (2_100K) initially formed in corresponding syntheses. This transition is accompanied by two‐fold decrease in cell volume and increase in cell symmetry. Recrystallyzation of 2–4 from common organic solvents affects the nuclearity of products (in case of 2 and 3) or subtly alters the structure of [Cd (OOCCym)2(phen)2] units (4). The optimal Cd to Mn ratio inspired studying solid‐state thermal decomposition of 2–4 as a route to CdMn2O4‐based ceramics. As a result, oxide samples with a predominance of tetragonal (Cd1‐xMnx)Mn2O4 spinel have been prepared and characterized by powder XRD, SEM, EDX, and IR revealing the interplay between the preparation technique and the features of morphology and composition. The retaining of Cd to Mn ratio upon recrystallyzation of 2–4 implies possibility of further elaboration of CdMn2O4‐based materials in various morphologies (polycrystalline ones, films, etc.). Notably, 2–4 is also the first series of related heterometallic Cd‐Mn complexes being studied as individual precursors for CdMn2O4‐based oxide systems. [ABSTRACT FROM AUTHOR]

Exchange reactions of LnCl3 and CymCO2K in aqueous‐organic medium in the presence of diethylene glycol (DEG) bring about isostructural tetranuclear cluster complexes with linear core, [Ln4(CymCO2)12(O(CH2CH2OH)2)2(H2O)4] ⋅ 2THF (Ln=Nd (1), Gd (2), Tb (3), Dy (4), Ho (5); Cym=(η5‐C5H4)Mn(CO)3). The complexes have centrosymmetric structure and contain two types of Ln3+ coordination centers. Thermal decomposition of the complexes under argon and air atmospheres was studied; in the latter case it brings about mixed oxides LnMn2O5 as one of the products. The complexes 1–5 were characterized by dc‐ and ac‐magnetic measurements. Complexes of Nd, Gd, and Dy exhibit the properties of single‐molecule magnets (SMMs) with remagnetization barriers Δeff/kB of 14 K for 1 under 2500 Oe dc‐field, 13 K for 2 under 1500 Oe dc‐field, and with two barriers, 18 and 19 K, for 4 in zero field. The presence of field‐induced slow relaxation of the magnetization detected for the complex 2 is a rare case for Gd complexes. [ABSTRACT FROM AUTHOR]

Slow relaxation of magnetization has been studied for a series of stable isomorphic 3D‐polynuclear Ln‐Co complexes comprising hexadentate [Co(CN)6]3– linkers, namely {[Ln(H2O)2][Co(CN)6]·2H2O}n where Ln = Tb (1), Dy (2), Er (3) and Yb (4). While 1 and 4 behave as field‐induced single‐ion magnets (SIMs), compounds 2 and 3 undergo rapid demagnetization even under magnetic fields up to 5000 Oe. The effective anisotropic energy barrier of 4 was estimated as 63 K (5000 Oe) which, to the best of our knowledge, is the highest value among Yb‐based SIMs. The obtained data are discussed in scope of the configuration of the Ln environment, i.e. accounting its composition and geometry as well as mutual arrangement of chemically unequal donating centers. Thus, the studied series of complexes represents very rare case when SIM performance of non‐dysprosium complexes far surpasses that of isomorphic Dy derivative. [ABSTRACT FROM AUTHOR]