Jan Taraba

Ni(II), Cu(II), and Zn(II) Diethyldithiocarbamate Complexes Show Various Activities Against the Proteasome in Breast Cancer Cells

A series of three complexes with diethyldithiocarbamate ligand and three different metals (Ni, Cu, Zn) was prepared, confirmed by X-ray crystallography, and tested in human breast cancer MDA-MB-231 cells. Zinc and copper complexes, but not nickel complex, were found to be more active against cellular 26S proteasome than against purified 20S proteasome core particle. One of the possible explanations is inhibition of JAMM domain in the 19S proteasome lid.

Glycoluril Dimers Bearing Hydrogen Atoms on Their Convex Face and Their Self-Assembly in the Solid State

A selective method for the synthesis of 1,6-substituted glycolurils has been developed. The glycolurils have been used for the synthesis of methylene-bridged glycoluril dimers bearing hydrogen atoms on their convex face. Depending on the side walls of the dimers, different modes of self-assembly in the solid state have been described using X-ray crystallography.

A new route to 1,4-disubstituted 5-thioxoperhydroimidazo[4,5-d]imidazol-2-ones

1,4-Disubstituted 5-thioxoperhydroimidazo[4,5-d]imidazol-2-ones were prepared by one-pot criss-cross cycloaddition reactions of 1,4-disubstituted 1,4-diazabuta-1,3-dienes with HNCS and HNCO generated in situ from potassium salts by acetic acid.

New isostructural ethylenediammonium diphosphates (NH3(CH2)2NH3)2[Me(HP2O7)2 · 2 H2O] [Me = Co, Ni] : X-ray crystal structure and vibrational spectroscopy

Abstract New ethylenediammonium diphosphates (NH3(CH2)2NH3)2[Me(HP2O7)2 · 2 H2O] [Me = Co (1), Ni (2)] have been synthesized and investigated by single-crystal X-ray diffractometry. The two structures resulted to be isostructural within triclinic space group P-1. The unit-cell parameters are: a = 7.5211(6) Å, b = 7.5574(3) Å, c = 9.7689(7) Å, α = 103.6(1)°, β = 111.14(1)°, γ = 98.04(1)°, V = 486.9(1) Å3 (1) and a = 7.4631(15) Å, b = 7.5274(12) Å, c = 9.743(3) Å, α = 104.28(2)°, β = 110.75(2)°, γ = 97.50(2)°, V = 481.4(2) Å3 (2). The three-dimensional network is built up by discrete Me(HP2O7)2 · 2 H2O moieties, which, via strong O—H … O bonds, form layers parallel to ab plane. Ethylenediammonium groups are located between such layers, stabilizing the framework via N—H … O bonds. The hydrogendiphosphate group presents bent eclipsed conformation, while the Me ion lies on inversion centre. The structural data, as the bent POP configuration, have been confirmed by the Raman and infrared spectra of the title compounds. In particular, the non-coincidence between the infrared and Raman bands supports the centrosymmetric structure of the investigated crystals.

The polysulfonylamines bis(methylsulfonamido) sulfone and bis(trifluoromethylsulfonamido) sulfone.

Bis(methylsulfonamido) sulfone, C(2)H(8)N(2)O(6)S(3) or SO(2)(NHSO(2)CH(3))(2), was synthesized from imidobis(sulfonyl chloride), HN(SO(2)Cl)(2), and bis(trimethylsilyl)methane, CH(2)[Si(CH(3))(3)](2), in chlorotrimethylsilane solution. In the solid state, there are two independent molecules linked by two N-H...O hydrogen bridges into infinite chains parallel to the b axis. The central S atoms of the independent molecules each lie on a twofold axis. Bis(trifluoromethylsulfonamido) sulfone, C(2)H(2)F(6)N(2)O(6)S(3) or SO(2)(NHSO(2)CF(3))(2), was formed by the reaction of trichlorophosphazosulfuryl trifluoromethane, Cl(3)PNSO(2)CF(3), with fluorosulfonic acid, FSO(3)H. The molecules are connected by bifurcated N-H...O bridges into infinite layers parallel to the [001] plane. The central S atom lies on a twofold axis.

Taming the Oxidative Power of SeO3 in 1,4-Dioxane, Isolation of Two New Isomers of Mixed-Valence Selenium Oxides, and Two Unprecedented Cyclic Esters of Selenic Acid

The reaction of (SeO3)4 with 1,4-dioxane (diox, dioxane) with or without diluting solvent led to the isolation of the unprecedented esters of selenic acid-1,2-ethyl selenate (CH2O)2SeO2 and the glyoxal diselenate O2Se[(OCHO)2]SeO2. It was possible to isolate an unknown dimeric form of Se2O5 (Se4O10·(diox)2) and a geometrical isomer of the mixed-valence oxide trans-Se3O7, both stabilized by dioxane. The dioxane adduct of monomeric selenium trioxide SeO3·diox was obtained from the reaction of (SeO3)4 with dioxane in liquid SO2. The reaction mechanism for the formation of these compounds was elucidated, and the molecular structure of the unstable form of the selenium trioxide was determined, consisting in a trimeric arrangement (SeO3)3.

New polyheteroatomic cyclic molecules containing elements of the 13.-16. group

During studies of the reactions of ─N(H)SiMe 3 and ─N(Me)SiMe 3 derivatives of Cl 3 PNSO 2 Cl with acetonitrile and BCl 3 we have obtained six-membered polyheteroatomic cycles ⌈P(Cl 2 )NSO 2 (Cl)N(H) C(Me)N⌉ and ⌈P(Cl 2 )NS(O)(Cl)OB(Cl 2 )N(Me)⌉.1, 2 In the system Ph 2 PCl 3 , H 2 NSO 2 Cl and HN(SiMe 3 ) 2 we have identified and isolated several P─N─S cycles, e.g. the reaction of Ph 2 PCl 3 with H 2 NSO 2 Cl gives Ph 2 ClPNSO 2 Cl3 which with HN(SiMe 3 ) 2 reacts to ⌈S(O 2 )N(H)P(Ph) 2 N(H)SO 2 N(H)P(Ph) 2 N(H)⌉, ⌈S(O 2 )N(H)S(O 2 )N(H)P(Ph) 2 N(H)P(Ph) 2 N(H)⌉ and ⌈[S(O 2 )N(H) P(Ph) 2 NP(Ph) 2 N(H)]+⌉ Cl−; Ph 2 PCl 3 with HN(SiMe 3 ) 2 gives N[P(Ph) 2 N(H)SiMe 3 ] 2 + Cl−, and H 2 NSO 2 Cl with HN(SiMe 3 ) 2 leads to SO 2 (NHSiMe 3 ) 2 . The reaction of Ph 2 PCl 3 with HN(SiMe 3 ) 2 gives N(P(Ph) 2 NHSiMe 3 ) 2 Cl in a very good yield which was further used to syntheses of metal-containing heterocycles. By the reaction of N[P(Ph) 2 N(H)SiMe 3 ] 2 +Cl− with some covalent halogenides we have obtained six-membered heterocycles containing B, As, In, and Sn. The same cyclic compounds can also obtained by the reaction of N[P(Ph 2 )NH 2 ] 2 +Cl− or HN(P(R 2 )N(H)SiMe 3 ) 2 with covalent halogenides.4−6 However, the synthetic route via N[P(Ph) 2 NHSiMe 3 ] 2 +Cl− is more convenient and gives the compounds in almost quantitative yields. The identity of all compounds was unambiguously establised by their X-ray structure determination.