Three mixed-ligand Cu(II) complexes with compositions [Cu(phen) 2 (SO 4 )]·CH 3 OH (1), [Cu(phen) 2 (SO 4 )]-(H 2 O) 2 (dmf) (2), and [Cu(phen) 2 H 2 O](SO 4 )(H 2 O) 4 (3), where phen = 1,10-phenanthroline and dmf = N,N′-dimethylformamide, were prepared and studied. These compounds belong to the landscape of the mononuclear Cu(phen) 2 sulfates, and the solvated complexes undergo frequent anion/water exchange at the metal center in aqueous solutions. Complexes are similar by the metal trigonal bipyramidal coordination geometry but differ by the mode of enclathration and number of protic and aprotic solvent guest molecules being accommodated in the crystal lattice. Crystal packing in 1−3 is determined by the robust supramolecular patterns that consist of stacking interactions between the planar extended phen fragments. These are observed in all three solids regardless of the interplay of other noncovalent interactions, including rather strong hydrogen bonds. The dual luminescence is detected at 580 and 470 nm for both crystals of phen and 3. Detailed analysis of singlet and triplet excitations in phen and 3 is performed by time-dependent density functional methods. Fluorescence is predicted with a low quantum yield at 386 nm, and dual phosphorescence from n−π* and π−π* triplet states is predicted at 523 and 496 nm. Emission quenching was demonstrated for 3 and explained by nonradiative decay involving supramolecular stacking and low-lying metal-centered states. ■ INTRODUCTIONFor decades Cu(II) coordination compounds have been attractive targets for magneto-and biochemistry. 1,2 Engineering of metal−organic materials with specific properties using a molecular building blocks approach is possible only by understanding the interplay of different interactions involved in self-assembly processes. From a crystal engineering perspective, one of the advantages of using transition metal ions is that the shape of the main building block can be controlled by way of organic ligand-bound metal-containing modules in directions dictated by the coordination geometry of the metal center and by careful choice of the ligands. 3−8 Design strategies employing simultaneously coordination bonds, hydrogen bonds, and π−π stacking interactions in crystal engineering are mostly not well documented so far. 9 We are involved in engineering, structural studies, and evaluation of properties of low-dimensional clusters and coordination polymers that include the Cu(II)−phen building block and reveal the contribution of stacking interactions in the crystal packing. 10,11 The necessity of careful examination and disclosure of the robust recurring patterns in such lowdimensional solids is dictated by their wide exploitation as medicinal forms with obvious antitumor efficacy. It has been reported that, in particular, phen derivatives [Cu-(CH 3 COO) 2 (phen)] and [Cu(sal)(phen)] demonstrate approximately seven times higher activity than cisplatin against HepG2, A-498, and A-549 cancer cells. Among the factors that influence the cytotoxic activity, the...

Herein we report the synthesis of some new 1H-1,2,4-triazole functionalized chromenols (3a–3n) via tandem reactions of 1-(alkyl/aryl)-2-(1H-1,2,4-triazole-1-yl) with salicylic aldehydes and the evaluation of their antifungal activity. In silico prediction of biological activity spectra with computer program PASS indicate that the compounds have a high novelty compared to the known antifungal agents. We did not find any close analog among the over 580,000 pharmaceutical agents in the Cortellis Drug Discovery Intelligence database at the similarity cutoff of 70%. The evaluation of antifungal activity in vitro revealed that the highest activity was exhibited by compound 3k, followed by 3n. Their MIC values for different fungi were 22.1–184.2 and 71.3–199.8 µM, respectively. Twelve from fourteen tested compounds were more active than the reference drugs ketoconazole and bifonazole. The most sensitive fungus appeared to be Trichoderma viride, while Aspergillus fumigatus was the most resistant one. It was found that the presence of the 2-(tert-butyl)-2H-chromen-2-ol substituent on the 4th position of the triazole ring is very beneficial for antifungal activity. Molecular docking studies on C. albicans sterol 14α-demethylase (CYP51) and DNA topoisomerase IV were used to predict the mechanism of antifungal activities. According to the docking results, the inhibition of CYP51 is a putative mechanism of antifungal activity of the novel chromenol derivatives. We also showed that most active compounds have a low cytotoxicity, which allows us to consider them promising antifungal agents for the subsequent testing activity in in vivo assays.

The title compound crystallises in the triclinic centrosymmetric space group P1̄ with an intriguing high number of crystallographically unique binary salt-like adducts (Z′ = 8) and a total number of ionic species (Z′′ = 16) in the asymmetric unit.

The combination of [Cu­(II)­(2,2′-bpy)]2+ and [Cu­(II)­(phen)]2+ (2,2′-bpy = 2,2′-bipyridine; phen = 1,10-phenanthroline) corner fragments predisposed to π–π stacking interactions with bridging ligands 4,4′-bipyridine (4,4′-bpy), 4,4′-bipyridinethane (bpe), and 4,4′-bipyridinepropane (bpp) in the presence of linear SCN–, or tetrahedral ClO4 – or BF4 – inorganic anions and/or organic acetate anion provides access to a series of new metal–organic materials including non-centrosymmetric polymeric chains, whose architectures were confirmed through single crystal X-ray crystallographic analysis. The nine reported compounds comprise one mononuclear complex, [Cu­(2,2′-bpy)2­(CH3COO)]­(SCN)­(H2O) (1), three binuclear complexes, [Cu2(2,2′-bpy)2­(CH3COO)2­(SCN)2(4,4′-bpy)]­0.5dmf (2), [Cu2(phen)2­(CH3COO)2­(SCN)2­(bpe)] (3), [Cu2(phen)2­(SCN)4­(bpe)] (4), and five one-dimensional coordination polymers, {[Cu­(2,2′-bpy)­(4,4′-bpy)­(ClO4)2]­(H2O)} n (5), {[Cu­(phen)­(4,4′-bpy)­(BF4)2]­(H2O)} n (6), {[Cu­(2,2′-bpy)­(ClO4)­(H2O)­(bpp)]­(ClO4)} n (7), {[Cu­(phen)­(ClO4)­(dmf)­(bpp)]­(ClO4)} n (8), and {[Cu­(phen)­(bpp)­(BF4)2]­[Cu­(phen)­(bpp)2­(BF4)]­(BF4)} n (9). Coordination polymers represent the neutral (5, 6), cationic (7, 8), or a blend of neutral and cationic chains (9), and differ by the Cu­(II) coordination cores, conformations of the bridging ligands, and functions of the anions. All compounds except 7 reveal cooperative π–π stacking interactions of corner fragments. As expected for the paramagnetic d9 Cu­(II) complexes, the polymeric solids show the luminescence quenching. The second order nonlinear optical properties of powders of the non-centrosymmetric compounds 8 and 9 were also tested.

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Versatility of copper(II) coordination compounds with 2,3-bis(2-pyridyl)pyrazine mediated by temperature, solvents and anions choice, Solid State Sciences (2018),

Eight Cu(II) coordination compounds with cyclic triimidazole, triimidazo[1,2-a:1’,2’-c:1”,2”-e][1,3,5]-triazine (L1), its positional isomer, triimidazo[1,2-a:1’,2’-c:1”,5”-e][1,3,5]-triazine (L2), and two pyridine derivatives of L1, 3-(pyridin-2-yl)triimidazo[1,2-a:1',2'-c:1'',2''-e][1,3,5]triazine (L3) and 3-(pyridin-4-yl)triimidazo[1,2-a:1',2'-c:1'',2''-e][1,3,5]triazine (L4) are reported. All compounds represent...

Abstract. Interaction of N-ethyl isatin 3 with dimethyl acetylenedicarboxylate in the presence triphenylphosphine has led to good selectivity of methyl 1'-ethyl-4-methoxy-2',5-dioxo-5H-spiro[furan-2,3'-indoline]-3-carboxylate 4 formation. Similar yields of spirolactones 6,8 were obtained by addition of dimethyl acetylenedicarboxylate to 5-bromo functionalized isatins 5,7. However, reaction of N-butyl isatin 9 resulted in formation of an inseparable mixture of compounds. Treatment of N-benzyl isatin 10 and dimethyl acetylenedicarboxylate with triphenylphosphine proceeded with reduced selectivity of the spirooxindole 11 formation.Keywords: spirolactones, isatins, triphenylphosphine, dimethyl acetylenedicarboxylate. IntroductionThe widespread distribution of butenolides in naturally occurring [1-3] and synthetic bioactive substances strongly motivate an interest for improving the methodology of the selective synthesis of butenolide functionalized spirooxindoles in high yield [4,5]. Such developments are of interest not only for the possible total synthesis of therapeutically useful spirooxindoles [6][7][8][9][10][11][12][13][14][15], but also for the preparation of synthetic analogs [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] in order to improve our knowledge in structure-activity relationships [12-14, 31, 32]. So-called butenolide functionalized spirooxindoles 1 provide the most interesting subject for synthetic investigations in view of the large and ever increasing number of the members of this family which have furan-2(5H)-one 2 as a building block (Scheme 1).