Dinuclear complexes [Ag2I2L2] and [Ag2I2L(PPh3)2] were synthesized using 2,3-bis(diphenylphosphino)pyridine, a previously unexplored ligand. The second complex was isolated as solvates with CHCl3 or Et2O molecules possessing the same molecular geometry, but very different intramolecular AgAg distances (3.630 and 3.098 & Aring;, respectively). At room temperature, both complexes [Ag2I2L2] and [Ag2I2L(PPh3)2] display strong blue-green luminescence with quantum yields of 32 and 62% and decay times of 6.9 and 12 ms, respectively.

The reaction of indole-3-glyoxylyl chloride with α,ω-azidoalkanols and α,ω-azidoalkylamines afforded azide analogues of indibulin. The latter were reacted with acetylene derivatives of 3,5-bis(benzylidene)piperidin-4-ones using click chemistry approaches. The resulting conjugates were tested for antiproliferative activity.

Tris{2''-[3'-(1,3-dioxoisoindol-2-yl)propoxy]phenyl}phosphine oxide (L) has been synthesized. The complexes of ligand L with U(VI), Th(IV) have been isolated and studied in solid state and chloroform solution by elemental analysis, IR, Raman, NMR spectra, and x-ray diffraction. Extraction properties of ligand L have been studied by the example of recovery of micro amounts of U(VI), Th(IV), and Ln(III) from 3 M NH4NO3 solutions into chloroform. In crystalline complex [UO2 L(H2O)(NO3)2], the ligand is coordinated by means of phosphoryl group, while one of the C & boxH;O groups forms hydrogen bond with coordinated water molecule. In the solid complex [Th2 L 3(H2O)5(NO3)8], phosphoryl groups of the ligands, nitrate anions, water molecules are coordinated, C & boxH;O groups form H-bonds. The results of the solutions study have been compared with extraction data. In solution, the complexes are formed due to coordination of phosphoryl group and stabilized owing to hydrogen bonds of carbonyl groups. This stabilization improves extraction ability. According to extraction study, compound L exhibits significantly higher extraction ability toward U(VI) and Th(IV) compared to phosphine oxide Ph3P(O), (BuO)3PO, and Ph2P(O)CH2CONBu2. The UV-vis spectra showed that complexation of ligand L with UO2 and Th nitrates does not affect considerably the character of absorption spectra.

This study presents a new class of coordination polymers synthesized from 1,2,4,5-tetrakis(diphenylphosphino) pyridine and trivalent Eu(III), Tb(III), and Gd(III) ions. The synthesized polymers exhibit a unique onedimensional periodic structure enabled by the bridging chelate nature of the ligand, and a noteworthy luminescent efficiency. Terbium and Europium complexes demonstrate high quantum yields and high purity luminescence colors. They are therefore promising materials for photonic devices such as OLEDs, where high- intensity monochromatic emission is required.

Reaction of tris[2-(2 '-pyridylmethoxy)phenyl]phosphine oxide (L) with f-element nitrates resulted in 1:1 complexes. The isolated complexes of ligand L with La(III), Eu(III), Tb(III), and U(VI) nitrates, and with La(III) chloride were studied in the solid state and solution by IR, Raman, and NMR spectroscopy, X-ray analysis, and also DFT calculations. Composition and structure of the complexes vary with lanthanide cation radius. According to the data of elemental analysis, vibrational spectroscopy, and X-ray diffraction, the ligand is coordinated in tridentate mode in crystalline La(III) and solid Eu(III) complexes:[Ln(OPO,N,Oeth-L)(H2O)(O,O-NO3)3], and in monodentate mode in crystalline complex [Tb(OPO-L)(H2O)2(O,O-NO3)3]. Nitrogen atoms of pyridine fragments of the ligand not involved in coordination produce intra- and intermolecular H-bonds with coordinated water molecules in the second coordination sphere of Ln(III). According to IR, NMR spectrometry, and DFT calculations, the structure of coordination polyhedron of the main species of Ln(III) complexes in acetonitrile solutions is retained including coordination of one of pyridine fragments in the second coordination sphere: [Ln{OPO,N, (N*),Oeth-L}(H2O)(O,O-NO3)3] and[Tb{OPO,(N*)-L}(H2O)2(O,O-NO3)3], where Ln = La, Eu, and N* is the nitrogen atom of pyridine fragment producing intramolecular H-bond with coordinated water molecule. According IR and Raman spectroscopy, ligand L is coordinated in bidentate mode in solid complex [UO2(OPO,N-L)(O,O- NO3)], and uncoordinated nitrogen atoms remain free. Solution structure of uranyl complex is labile and depends on solvent nature. Equilibria of complex species with variable coordination of nitrate ions, ligand L , and with probable involvement of water take place in CD3CN and CDCl3 solutions. Photophysical properties of the prepared Eu(III) and Tb(III) complexes were studied. The preliminary assessment of extraction properties of compound L was made. Stability of studied compounds in acetonitrile solutions was examined, and the structure of one of protolysis product of Eu(III) complex, [Eu(LH)(H2O)(NO3)4], was established by micro-IR and X-ray analysis.

Chemotherapy with anthracycline antibiotics is a common method of treating tumors of various etiologies. To create more highly effective cytostatics based on daunorubicin, we used the method of reductive amination using polyalkoxybenzaldehydes. The obtained derivatives of the anthracycline structure have much greater cytotoxicity compared to daunorubicin due to increased affinity for DNA, the ability to disrupt the cell cycle, and their inhibition of the glycolysis process, which is confirmed by data from extensive biological studies and the results of molecular modeling.

A new luminescent Mnii complex based on 1-benzyl-3,4-bis(diphenylphosphoryl)pyrrolidine ligand has been synthesized and fully characterized. This complex exhibits intense luminescence in the solid state (lem = 585 nm) with a high quantum yield (60%) as well as luminescence lifetime of 17 ms.

A simple method for modifying sesquiterpene lactones with 3,5-bis(arylidene)piperi-din-4-ones using the phase-transfer catalytic aza-Michael addition in the MeCN—K2CO3 system was developed. Molecular docking revealed that the synthesized conjugates of isoalantolactone, alantolactone, and dehydrocostus lactone with various bis(arylidene)-piperidones directly interact with the DNA binding site of the p50 subunit of nuclear factor κB, which may be indicative of their ability to induce apoptotic death of the tumor cells due to activation of the death receptor expression and, thereby, to exhibit an antitumor effect.

The extraction of U(VI), Th(IV), Am(III), and Eu(III) with solutions of phosphorylated pyridines from nitric acid solutions has been studied. The stoichiometry of the extractable complexes was established. In terms of their extraction ability, these compounds are inferior to bis(diphenylphosphinyl)methane, but they are significantly superior to carbamoylmethylphosphine oxides. An increase in the number of phosphine oxide groups in the molecules of phosphorylated pyridines leads to a significant decrease in their extraction ability and selectivity in the extraction of Am(III) and Eu(III) from nitric acid solutions.

Using triterpenoid betulin as an example, a convenient method for the synthesis of 5,6-dihydropyran derivatives containing a nor-triterpenoid fragment at position 4 was proposed. The method involves the reaction of lupane triterpenoids with paraformaldehyde in dioxane in the presence of sulfuric acid. Approaches to the synthesis of triterpene derivatives of 5,6-dihydropyran-2-one and penta-2,4-dienoic acid were developed based on the obtained 4-(3,28-diacetoxy-20,29,30-tri-nor-lupan-19-yl)-5,6-dihydropyran. Triterpene-substituted penta-2,4-dienoic acid heated with triphenylphosphonium triflate formed a quaternary phosphonium salt, which showed cytotoxicity against human cancer cells MCF-7 (breast cancer) and HCT116 (colon cancer) with IC50 4–19 µmol L−1, with its activity against these cell lines being superior to the activity of the comparison drug camptothecin.

The reaction of 1,2,4,5-tetrakis(diphenylphosphinyl)benzene with Eu(ONO2)3∙6H2O led to the formation of a new coordination polymer exhibiting a bright red glow when excited in a wide ultraviolet range (Qin = 19.9%).

A series of (2–carbamoyl ethyl)diphenylphosphine oxides (KFO) has been synthesized from commercially available reagents — diphenyl chlorophosphine and acrylamides. The influence of the number of ligand fragments of Ph2P(O)(CH2)2C(O), the nature of the oligoyl radical binding these fragments, as well as the presence of additional coordination centers in the KEFO molecule on the extraction properties of KEFO with respect to actinides and lanthanides was investigated. It was found that N,N′-methylene-bis[3-(diphenylphosphoryl) has the greatest efficiency in the extraction of actinidespropionamide] (III), in which two diphenylphosphorylpropionyl radicals are bound by a rigid HNCH2NH linker (the degree of extraction of U(VI) reaches ~73%, and Th(IV) — ~85%), while in the case of lanthanides, on the contrary, ligand V, containing the maximum amount of this kind of phosphoryl carbonyl radicals attached to a conformationally non-rigid nitrogenous heterocyclic matrix, as well as KEFO (II), containing an additional C=O group in an alkyl radical attached to a nitrogen atom, has significant advantages carbamoyl fragment (when using this compound, gadolinium extraction is close to 92%). The obtained data show that highly effective and selective extractants of both 4fand 5felements can be created on the basis of (2-carbamoyl ethyl)diphenylphosphine oxide structure.

The coordination and extraction properties of two related tripodal ligands differed by types of addition of the triazole fragment and linker length in the 2-[(4-Ph-1,2,3-triazol-1-yl)CH2CH2O]C6H43P(O) (L1) and 2-[(1-Ph-1,2,3-triazol-4-yl)CH2O]C6H43P(O) (L2) are compared. The structures of the complexes [Lа(NO3)3L1] (I) and [Lu(NO3)3L1] (II) are studied in the solid phase (elemental analysis, IR and Raman spectroscopy) and in solutions (IR and multinuclear 1H, 13C, and 31P NMR spectroscopy). A normal coordinate analysis at the TPSS-D4/Def2-SVP level is performed for an isolated molecule of the model complex [LaP(O),N3,N2-L3(O,O-NO3)3] (L3 = 2-[(4-Me-1,2,3-triazol-1-yl)CH2CH2O]C6H43-P(O)). According to the set of spectral and quantum chemical data, ligand L1 exhibits the tridentate P(O),N2,N2 coordination in lanthanide complexes I and II. These are neutral complexes in the solid state and in CD3CN solutions, and the dynamic equilibrium of the neutral and ionic complexes is observed in CDCl3. Unlike ligand L1, ligand L2 exhibits the tetradentate P(O),N3,N3,N3 coordination in the [Ln(NO3)3L2] complexes with the same metals (Ln = La3+, Lu3+) in solutions. The efficiency of extraction of microquantities of f elements from the aqueous phase to 1,2-dichloroethane by compounds L1 and L2 is discussed in comparison with the structures of the complexes of both ligands in solutions.

Coinage metal(i) complexes exhibiting thermally activated delayed fluorescence (TADF) have attracted worldwide attention as emitters for OLEDs. Reducing the emission lifetime and improving the quantum efficiency of such emitters is a current challenge in this hot field. To address this issue (challenge), a symmetry-based design strategy has been applied herein to obtain pseudo-symmetric complexes [M2(tdpb)(NHC)2]2+ (M = Cu, Ag, Au) scaffolded by 1,2,4,5-tetrakis(diphenylphosphino)benzene (tdpb) and N-heterocyclic carbene (NHC) ligands. In the solid state at ambient temperature, the synthesized compounds exhibit cyan to yellow TADF of the metal-to-ligand charge transfer type with excellent quantum yields (58-89%) and short decay times (2.5-15 mu s). It is shown that the symmetry-based design strategy leads to a significant increase in the radiative rate constants for the "dimers" [M2(tdpb)(NHC)2]2+ compared to the "monomers" [M(dppb)(NHC)]+ based on 1,2-bis(diphenylphosphino)benzene (dppb). The practical potential of the developed TADF emitters was also demonstrated through their application as innovative thermo- and vapor-chromic emission inks for advanced anti-counterfeiting labels.

A new phosphine oxide derivative, tris2-[N-(quinolin-8-yl)carbamoylmethoxy]-phenylphosphine oxide, was synthesized by the alkylation of tris(2-hydroxyphenyl)-phosphine oxide. The synthesized compound exhibits the properties of a tripodal polytopic O,N ligand with respect to lanthanum and terbium cations. The composition and structures of the ligand and its complexes were determined by elemental analysis, vibrational and multinuclear NMR spectroscopy (1H, 13C, 31P), and X-ray diffraction.

Effect of ionic liquid 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide on the extraction of U(VI), Th(IV), and lanthanides(III) from nitric acid solutions with phosphorylureas RR'P(O)NHC(O)NHC8H17-n that differ in the nature of substituents at the phosphorus atom has been studied. A considerable synergistic effect has been revealed on the extraction of metal ions in the presence of the ionic liquid in organic phase. The stoichiometry of extracted complexes has been determined. The influence of extractant structure, organic diluent nature, and HNO3 concentration in aqueous phase on the efficiency of metal ions extraction into organic phase has been considered.

The Mitsunobu reaction of tris(2-hydroxyphenyl)phosphine oxide with N-(3-hydroxypropyl)-4-nitro-1,8-naphthalimide resulted in alkylation of only two phenolic groups. The aromatic nitro groups of the synthesized product were replaced by the BuNH groups by the reaction with butylamine. The synthesized product exhibited fluorophore properties.

A new efficient synthesis of racemic (R*,R*)-Pyrphos ligand based on aza-Michael addition reaction of 2,3-bis(di- phenylphosphoryl)buta-1,3-diene with ammonia followed by the reduction of resulting 3,4-bis(diphenylphosphoryl)- pyrrolidine is proposed. The starting reactants are available but-2-yne-1,4-diol and chloro(diphenyl)phosphine.

In recent years, researchers have often encountered the significance of the aberrant metabolism of tumor cells in the pathogenesis of malignant neoplasms. This phenomenon, known as the Warburg effect, provides a number of advantages in the survival of neoplastic cells, and its application is considered a potential strategy in the search for antitumor agents. With the aim of developing a promising platform for designing antitumor therapeutics, we synthesized a library of conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones. To gain insight into the determinants of the biological activity of the prepared compounds, we showed that the conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones, which are cytotoxic agents, demonstrate selective activity toward a number of tumor cell lines with glycolysis-inhibiting ability. Moreover, the results of molecular and in silico screening allowed us to identify these compounds as potential inhibitors of the pyruvate kinase M2 oncoprotein, which is the rate-determining enzyme of glycolysis. Thus, the results of our work indicate that the synthesized conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones can be considered a promising platform for designing selective cytotoxic agents against the glycolysis process, which opens new possibilities for researchers involved in the search for antitumor therapeutics among compounds containing piperidone platforms.

Rare-earth element-free materials that exhibit strong room temperature phosphorescence (RTP) and X-ray scintillation properties are gaining global interest incessantly in the recent years. This work reports a series of easily synthesizable cubane Cu4I4-triarsenic clusters [Cu4I4(R3As)3L] (L = none or nitrile), that exhibit a strong yellow-green RTP with quantum efficiencies up to 100% and short decay times (4.4-4.9 mu s). The title cluster complexes display X-ray scintillation properties with a record ultralow detection limit (18.1 nGy s-1) and a perfectly linear dose rate response within a remarkably wide dose rate window (0-640 mu Gyair s-1). The cluster [Cu4I4(Ph3As)3] is highlighted as an efficient phosphor for UV-pumped white and yellow LED devices, demonstrating an excellent white spectrum with a CIE index of (0.32,0.33) and bright yellow emission, respectively. These results may stimulate the future efforts in designing highly efficient arsenic-based RTP materials and enriching the Cu4I4 cluster family. Herein an unprecedented triarsenic clusters [Cu4I4(R3As)3L] (L = none or nitrile) are reported to exhibit a yellow-green phosphorescence with the quantum efficiency of up to 100% as well as remarkable X-ray scintillation properties with a low-record limit of low detection just 18.1 nGyair s-1. Cluster [Cu4I4(Ph3As)3] is also demonstrated as an efficient phosphor for LED devices, which exhibit an excellent bright white and yellow emission. image