THERMOSTABLE EPOXIDE COMPOSITION BASED ON AROMATIC DIAMIDODISULFOIMIDE RESIN

New epoxide oligomers have been obtained by the interaction of p-phenylenediaminediamidodisulfoimide with a large excess of epichlorohydrin in the presence of triethylbenzylammonium chloride. The synthesized epoxide oligomers are a viscous product of dark brown color, well soluble in aprotic solvents (DMFA, DMSO), as well as in acetone and dioxane. These cooligomers include hydroxynaphthylene and phenylenediimine structural fragments possessing solubility, meltability and high reactivity in the reactions with the oxirane ring of epoxide compounds in composition of macromolecules. The cooligomer of m-phenylenediamine with α-naphthol was used for curing of diamidodisulfoimide resin.

A Study on the Rearrangement of Dialkyl 1-Aryl-1-hydroxymethylphosphonates to Benzyl Phosphates

The phospha-Brook rearrangement of dialkyl 1-aryl-1-hydroxymethylphosphonates (HPs) to the corresponding benzyl phosphates (BPs) has been elaborated under solid-liquid phase transfer catalytic conditions. The best procedure involved the use of triethylbenzylammonium chloride as the catalyst and Cs2CO3 as the base in acetonitrile as the solvent at room temperature. The substrate dependence of the rearrangement has been studied, and the mechanism of the transformation under discussion was explored by quantum chemical calculations. The key intermediate is an oxaphosphirane. The one-pot version starting with the Pudovik reaction has also been developed. The conditions of this tandem transformation were the same, as those for the one-step HP→BP conversion.

"POLYHEDRAL CONTRACTION" OF TETRAMETHYLAMMONIUM CLOSO-CARBOUNDECABORATE UNDER ACTION OF TRIS(TRIPHENYLPHOSPHINE)RUTHENIUM DICHLORIDE

In this paper the objectives were not only to investigate new promising methods leading to a deep structural rearrangement of carboranes and metallacarboranes but also to try to fix, to isolate and to characterize the intermediates. At the same time considerable attention is paid to the so-called "anti-wade" clusters formed during the reactions, the electronic structure of which does not correspond to their actually observed geometry. It is shown that the interaction of 11-vertex monocarbon closo-carboundecaborane with tris(triphenylphosphine)ruthenium dichloride leads to a series of new metallacarborane complexes. For the first time it was possible to control the process of "polyhedral contraction" of carborane {CB10} → (RuCB10} → {RuCB9} → {RuCB8} → {RuCB6} on the example of ruthenium complex and also to confirm experimentally each stage of the whole process. As a result of the reaction clusters of classical type and electron-deficient isocloso-/hypercloso-rutenacarborans {RuCB8}, {RuCB9} with 2n skeletal electrons were isolated. It is found that the interaction of tetramethylammonium closo-carboundecaborate with tris(triphenylphosphine)ruthenium dichloride proceeds in several stages. The first intermediate 12-vertex cluster is formed by mixing the initial reagents under heterogeneous conditions (methanol-THF, K2CO3, triethylbenzylammonium chloride) at room temperature for 10 hours. When the resulting complex is stirred in a mixture of methanol-THF solvents for 7 days at 20 °C, its almost quantitative transition to 11-vertex rutenacarborane was observed. Further transformation with the formation of a 10-vertex isocloso-rutenacarborane occurs when the methanol solution of this complex is boiled for 15 minutes. When the complex is boiled in methanol for 8 hours we obtained another extraordinary metallacarborane belonging to the rare 8-vertex pileo-clusters with a boron vertex built over the triangular face.

Synthesis of New Dihydroquinopimaric Acid Analogs with Nitrile Groups as Apoptosis-Inducing Anticancer Agents

Background: Cyan-containing compounds are of great interest as potential anticancer agents. Terpenoids can severe as a natural matrix for the development of promising derivatives with antitumor activity. Methods: The 2-cyanoethoxy methyl dihydroquinopimarate derivatives (5-9) were synthesized by the reaction of the intermediates (1-4) with acrylonitrile in the presence of alkali (30% KOH solution) using triethylbenzylammonium chloride. The cytotoxicity evaluation was carried out according to the National Cancer Institute (NCI) Protocol, while apoptosis was studied by flow cytometric analysis of Annexin V and 7-aminoactinomycin D staining and cell cycle was analyzed using the method of propidium iodide staining. Results: Synthesis of new dihydroquinopimaric acid derivatives with nitrile groups was carried out. The obtained cyanoethyl derivatives were converted into tetrazole, amine, oxadiazole and amidoxime analogs. The primary screening for antitumor activity showed the highest cytotoxic potency of the cyanoethyl-substituted compounds. The introduction of cyanoethyl groups at C-1, C-4 and C-1, C-4, C-20 positions of dihydroquinopimaric acid methyl ester provided antiproliferative effect towards the Jurkat, K562, U937, and HeLa tumor cell cultures (CC50=0.045-0.154µM). These nitrile derivatives are effective inducers of tumor cell apoptosis affecting the S and G2 phases of the cell cycle in a dose-dependent manner. Conclusion: The cyanoethyl analogs of dihydroquinopimaric acid reported herein are apoptosis inducers and cytotoxic agents. These findings will be useful for the further design of more potent cytotoxic agents based on natural terpenes.

A Novel and Chemoselective Process ofN-Alkylation of Aromatic Nitrogen Compounds Using Quaternary Ammonium Salts as Starting Material

The process ofN-alkylation of several pyrroles, indoles, and derivative heterocycles is herein described, using quaternary ammonium salts as the source of an alkylating agent. These reactions were carried out on several heterocyclic rings with triethylbenzylammonium chloride or tetradecyltrimethylammonium bromide and an NaOH solution at 50%, leading to a chemoselectiveN-alkylated product and an average yield of 73%. This is an alternative process to the traditional benzylation and methylation ofN-heterocycles with direct handling of alkyl halides.

First and efficient synthesis of 4-[((3,4-dihydroxybenzoyl)-oxy)methyl]-phenyl-β-D-glucopyranoside, an antioxidant from Origanum vulgare

4-(3,4-Dihydroxybenzoyloxymethyl)phenyl-O-?-D-glucopyranoside (DBPG, 1 ), a polyphenolic glycoside previously isolated from Oregano(Origanum vulgare L.) in 0.08% isolated yield, was synthesized in five chemical steps with 41.4% overall yield. First, 4-(hydroxymethylphenyl)-2,3,4,6-tetra-O-acetyl-b-D-glucopyranoside 4 was obtained in 53.2% yield by selective glycosylation of 4-hydroxybenzyl alcohol 3 with 2,3,4,6-tetra-O-acetyl-?-D-glucopyranosyl bromide 2 in a mixture of chlorobenzene and aqueous CsOH using triethylbenzylammonium chloride (TEBAC) as a phase transfer catalyst. Then, this product was esterified with 3,4-diacetoxylbenzoyl chloride 7 to generate 4-(3,4-diacetoxybenzoyloxy-methyl) phenyl 2,3,4,6-tetra-O-acetyl-b-D-glucopyranoside 8 in 95% yield. Finally, selectively global deacetylation of 8 was performed in a mixture of dibutyltin oxide and methanol under reflux to afford 1 in 94.8% yield.

Synthesis of new copolymers 4,4’-sulfinylbisphenol derivative with N-vinyl-2-pyrrolidone - photopolymerization and thermo-mechanical studies

Synthesis, structure and characterization of the new sulfur monomer sulfinylbis[benzene-4,1-diyl(oxy-2-hydroxypropane-3,1-diylmethacrylate)] (SO.DM) and its photopolymerization with N-vinyl-2-pyrrolidone (NVP) are presented. SO.DM was obtained in the three-step reaction. In the first step, 4,4’- sulfinylbisphenol from 4-[(4-hydroxyphenyl)thio]phenol was obtained. In the second step the epoxy compound was synthesized. It was obtained in the reaction of 4,4’- sulfinylbisphenol with 2-(chloromethyl)oxirane in the two phases liquid/liquid system including organic and aqueous phases. In the third step, ring opening of the obtained diglycidyl ether was carried out with the use of methacrylic acid in the presence of triethylbenzylammonium chloride (TEBAC) as a catalyst. Structures of new compounds were confirmed by spectroscopic methods (FT-IR, 1H and 13CNMR and DIP-MS). Photopolymerization of compositions containing different ratios of the monomers (SO.DM and NVP) and an initiator (Irgacure 651) was carried out. The following properties (before and after curing) were determined: density, polymerization shrinkage, glass transition temperature, Young’s modulus, hardness, tensile strength. Moreover, dynamic-mechanical and thermal properties were studied.