Volume 70, Issue 1

[bmim][HPy][S 2 O 7 ] [monoclinic, P 2 1 / n , Z = 4, a = 825.78(2), b = 1545.30(3), c = 1410.80(3) pm, β = 104.726(1)°, V = 1741.16(7) Å 3 ] was obtained as a side product in the reaction of GeCl 4 , oleum (65% SO 3 ), and the pyridine (Py) complex Py·SO 3 in the ionic liquid 1-butyl-3-methylimidazolium hydrogensulfate, [bmim][HSO 4 ], at 50 °C. Charge compensation of the disulfate ion is achieved by the counterions pyridinium, [HPy] + , and 1-butyl-3-methylimidazolium, [bmim] + . The crystal structure shows alternating layers of [bmim] + cations on one hand and [HPy] + cations and disulfate anions on the other hand. Pyridinium disulfate, [HPy] 2 [S 2 O 7 ] [orthorhombic, P 2 1 2 1 2 1 , Z = 4, a = 801.35(1), b = 1257.62(2), c = 1357.22(3) pm, V = 1367.80(4) Å 3 ] was formed unexpectedly in the reaction of Eu 2 O 3 and Py·SO 3 in pyridine. The crystal structure exhibits a layer-like arrangement of disulfate and pyridinium moieties in the ab plane. In both compounds, the disulfate groups are essentially uncoordinated allowing for a detailed inspection of “naked” S 2 O 7 2– ions.

N , N , N ′, N ′, N ″, N ″-Hexamethylguanidinium chloride 9c was prepared by treating the reaction mixture formed from N , N , N ′, N ′-tetramethylurea ( 1a ) and phthaloyl chloride ( 16 ) with dimethyltrimethylsilylamine 15 . N , N , N ′, N ′-Tetramethyl-chloroformamidinium chloride ( 2a ) is an intermediate in this synthesis. The chloroformamidinium chloride 2a can also be prepared by treating the urea 1a with thionyl chloride or phosphorus pentachloride, respectively. The guanidinium salt 9c can be obtained from the crude 2a thus prepared and the silylamine 15 . From urea/phosphoryl chloride adducts and primary aromatic amines have been prepared guanidines 38 , which are converted to N , N ′-diaryl- N , N ′, N ″, N ″-tetramethyl-guanidinium iodides 39 on treatment with methyl iodide. The N , N ′, N ″-trimethyl- N , N ′, N ″-triphenylguanidinium salt 44a was prepared from the chloroformamidinium salt 43 and N -methylaniline. The guanidinium salt 9c is the reaction product when the urea 1a /POCl 3 adduct is treated with the silylamine 15 .

An acidic ionic liquid 3-methyl-2-(1-sulfobutyl)-1 H -imidazolium hydrogensulfate, [BSO 3 HMIm]HSO 4 , was used as an efficient catalyst for the synthesis of a variety of pyrrole derivatives via a one-pot, three-component condensation of amines, nitroolefins, and 1,3-dicarbonyl compounds. Good to excellent yields of 72–96% were obtained under reflux in ethanol. The catalyst could easily be recovered and recycled up to six times, resulting in good yields without prolonging the reaction time. This method was also efficient in large-scale preparation. The procedure could be easily expanded to a one-pot, four-component reaction. This ionic liquid-catalyzed reaction provided an environmentally friendly alternative to the synthesis of pyrrole derivatives.

In our efforts to investigate the influence of alkali-metal ions on the formation of metal complexes with polyhalogen-substituted benzenedicarboxylates, two manganese(II) complexes of tetrachlorophthalic acid (1,2-H 2 BDC-Cl 4 ), [Mn 2 (1,2-BDC-Cl 4 ) 2 (H 2 O) 9 ]·H 2 O ( 1 ) and [MnK 2 (1,2-BDC-Cl 4 ) 2 (H 2 O) 4 ] n ( 2 ), were synthesized and structurally characterized. Single-crystal X-ray diffraction studies have revealed that complexes 1 and 2 crystallize in space groups P 1̅ and Pbcn , respectively. Complex 1 shows a discrete dinuclear structure, while complex 2 features a two-dimensional heterometallic framework containing rare Mn–O–K linkages. The results clearly suggest that the introduction of alkali metal ions does play a critical role in the construction of complexes 1 and 2 with distinct dimensionality and connectivity. Their spectroscopic, thermal, and fluorescence properties have also been studied briefly.

A new series of fused 1,2,4-triazoles, namely 6-aryl-3-(furan-2-yl)-[1,2,4]triazolo[3,4- b ][1,3,4]thiadiazoles 3a – h and 4a – f as well as 6-aryl-3-(furan-2-yl)-7 H -[1,2,4]triazolo[3,4- b ][1,3,4]thiadiazines 5a – h , were synthesized by the condensation of 4-amino-5-(furan-2-yl)-4 H -1,2,4-triazole-3-thiol ( 2 ) with substituted aromatic acids and phenacyl bromides, respectively. The structures of the newly synthesized compounds were established using spectroscopic analysis, while that of 3e was confirmed independently by a single-crystal X-ray structure determination. The compounds were evaluated for their antiviral activity against the replication of HIV-1 and HIV-2 in MT-4 cells using an MTT assay. In a docking study, 4b interacted with several amino acids in the reverse transcriptase (RT) binding site of HIV-1. Some new analogues were selected for evaluation of their Eg5 inhibitory activity using an in vitro malachite green ATPase assay. The QSAR of these new analogues was studied as well.

The semirigid bipyrazolyl and tripyrazolyl ligands, namely 1,4-bis((3,5-diphenyl-1 H -pyrazol-4-yl)-methyl)benzene (H 2 L 1 ) and 1,3,5-tris((3,5-diphenyl-1 H -pyrazol-4-yl)methyl)benzene (H 3 L 2 ), and their Cu(I) complexes (Cu 2 L 1 ) n ( 1 ), Cu 4 (HL 2 ) 2 ( 2 ) have been prepared and structurally characterized. Single-crystal X-ray analysis demonstrates that 1 exhibits a 2D structure featuring cyclic trinuclear Cu 3 pz 3 subunits. Complex 2 is a tetranuclear compound in which the tripyrazolyl ligand is partially deprotonated and acts as a μ 4 bridge connecting four Cu(I) atoms.

Ferrocenyl aryl ethers can be synthesized in good yields by Cu(I)/phosphine-catalyzed coupling reactions from iodoferrocene or 1,1′-dibromoferrocene and various phenols in toluene, using Cs 2 CO 3 or K 3 PO 4 as a base. For the first time a solid-state structure of a ferrocenyl-1,1′-diaryl ether [1,1′-di(4- tert -butylphenoxy)ferrocene] has been determined from single-crystal X-ray data. The mixed ferrocenyl aryl ether 1-(4- tert -butylphenoxy)-1′-(2,4-dimethylphenoxy)ferrocene was prepared in a two-step synthetic protocol.

A new prenylated acridone alkaloid, medicacridone ( 1 ), and a new ferulate xanthone, medicaxanthone ( 5 ), together with 11 known compounds were isolated from the methanol extract of the bark of the Cameroonian medicinal plant Citrus medica . The structures of all compounds were determined by comprehensive analyses of their 1D and 2D NMR, mass spectral (EI and ESI) data, chemical reactions, and comparison with previously known analogues. The agar diffusion test delivered low to missing antimicrobial activities, corresponding with MICs > 1 mg mL –1 , while compounds 1 – 6 and atalantoflavone ( 9 ) displayed weak cytotoxic activity against the human Caucasian prostate adenocarcinoma cell line PC-3, with IC 50 values ranging from 60.5 to 80.0 μ m versus doxorubicine with IC 50 =0.9 μ m .

Substituted phenols with a m -terphenyl backbone 2,4,6-R 3 C 6 H 2 OH [R=2,4,6-Me 3 C 6 H 2 ( 1 ), Me 5 C 6 ( 2 )] were synthesized using Kumada cross-coupling reactions between 2,4,6-I 3 C 6 H 2 OH and the corresponding Grignard reagent. Both compounds were structurally characterized in solution by 1 H and 13 C NMR spectroscopy and HRMS. The molecular structures of 1 and 2 were determined by single-crystal X-ray diffraction.

2-Ethyl-1-phenylindazolium hexafluorophosphate was deprotonated by potassium 2-methyl-butan-2-olate to give the N -heterocyclic carbene of indazole, i.e., indazol-3-ylidene. This N -heterocyclic carbene undergoes a ring transformation to 9-ethylaminoacridine. Trapping of the carbene with sulfur, silver(I) oxide, and carbonylbis(triphenylphosphane)rhodium(I) chloride resulted in the formation of indazolethione, indazolone (X-ray structure analysis), and carbonylbis(triphenylphosphane)(2-ethyl-1-phenyl-1 H -indazol-3-ylidene)rhodium(I) hexafluorophosphate (X-ray structure analysis), respectively. Reaction of the indazolium salt with phenolate and thiophenolate gave an N -ethyl-2-(phenylamino)benzimidate and benzimidothioate, respectively.