The 1:1 complexes of two unsaturated esters with 2,2,2-trifluoroethanol (TFE) were investigated experimentally and computationally. The experimental observations of the spectral shifts of the OH-stretching vibrational transitions were obtained at 113 cm−1 for TFE–methyl acrylate (MA) and 92 cm−...

An account of the total synthesis of stephanotic acid methyl ester and celogentin C is presented. The present synthesis features a tandem asymmetric Michael addition/bromination sequence for the synthesis of leucine-tryptophan moiety, and an oxidative coupling reaction to form the tryptophan-imi...

A series of novel, heteroaryl carboxylic acid conjugates of the sesquiterpene melampomagnolide-B (MMB, 3) has been evaluated as antitumor agents against an NCI panel of 64 human hematopoetic and solid tumor cell lines. The indole-3-acrylic acid conjugate 7j and the indole-3-carboxylic acid conju...

In a wide research programme towards the study of piperidin-4-ones with efficient pharmacological effect, a new series of N-acyl r-2,c-6-bis(4-methoxyphenyl)-c-3,t-3-dimethylpiperidin-4-ones 2–5 are synthesized and characterized by IR spectra, 1H, 13C, DEPT - 135 and 2D (COSY and HSQC) NMR and ...

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 2-(4-methoxyphenyl)-4,5-dimethyl-1H-imidazole 3-oxide have been investigated experimentally and theoretically. Gauge-including atomic orbital 1H NMR chemical shifts calculations were carried out ...

We report a series of tubulin targeting agents, some of which demonstrate potent antiproliferative activities. These analogs were designed to optimize the antiproliferative activity of 1 by varying the heteroatom substituent at the 4′-position, the basicity of the 4-position amino moiety, and c...

N-type single-walled carbon nanotubes fabricated by doping of organic dopant, 2-(2-methoxyphenyl)-1,3-dimethyl-2,3-dihydro-1H-benzo[d]imidazole, shows remarkable air-stability for over 90 days under atmospheric environment. Formation of stable complex between cationic dopant and anionic SWCNT is...

A new angelol-type coumarin glucoside, 6-[(1R,2R)-1, 2-dihydroxy-3-β-d-glucosyloxy-3-methylbutyl]-7-methoxycoumarin, was isolated from the roots of Angelica pubescens. Its structure was elucidated on the basis of spectral analysis.

Pre-treatment of stationary phase cells of Lactobacillus plantarum NCMIB 8826 with citric acid (pH 3 to 6) for a short period of time significantly improved subsequent cell survival in several highly acidic fruit juices namely cranberry (pH 2.7), pomegranate (pH 3.5), and lemon & lime juices (pH...

The non-polar lipid content and fatty acid (FA) composition of 11 mushroom species of the family Boletaceae were determined. The non-polar lipid content ranged from 2.0 (Leccinum aurantiacum and Boletus erythropus) to 5.4 % (w/w) d.w. (Suillus grevillei) with an average value of 2.9 %. More than...

The objective of this work has been to learn how to inhibit chemically the pentaboraneoxygen reaction with a view to developing improved fire protection systems. Rates of pyrolysis of pentaborane and ignition induction times of pentaboraneoxygenargon mixtures were measured in a shock tube ...

In an objective to synthesize metallaheteroboranes containing heavier chalcogen atoms, we performed the reaction of dimetallaborane analogues of pentaborane(9) with various chalcogen sources. As a result, the thermolysis of nido-[1,2-(Cp*RuH)2B3H7], 1 (Cp* = η5-C5Me5) with mixture of S and Se p...

Treatment of [Nb(η-C5H5)2H3] with pentaborane(9) gives the novel arachno-metallaboranes [Nb(η-C5H5)2B4H9] (1) and [Nb(η-C5H5)2B3H8] (2). Compound 1 is the first reported base subrogated analogue of the neutral arachno-pentaborane(11) and has an apex to niobium hydrogen bridge. Compound 2, for...

The reaction product from ethylene and pentaborane in the presence of aluminium chloride has been examined by infra-red spectroscopy and gas chromatography and has been shown to consist of unchanged pentaborane, ethyl pentaborane, together with a small quantity of material which is probably meth...

The reaction of pentaborane(9) with NaCN occurs in a 1:1 molar ratio at temperatures between − 30° and + 10°C to yield the complex Na[B5H9CN], which can be isolated in the form of a dioxanate. When excess pentaborane(9) is used the reaction is relatively clean and yields predominantly the [B9H...

New investigations of pentaborane(9) in the areas of halogenation, isomerization, coupling reactions and metalloborane synthesis are discussed within the framework of previous knowledge and more recent revelations.

[(η5-C5R5)Fe(PMe3)2H] (R = H, Me) can be made in good yields in a simple one-pot reaction between FeCl2, PMe3, C5R5H (R = H, Me) and Na/Hg in thf. Reaction of [(η5-C5H5)Fe(PMe3)2H] with pentaborane(9) gives the known metallaborane [(η5-C5H5)-nido-2-FeB5H10] (1) in improved yield as well as th...

The normal mode frequencies and corresponding vibrational assignments of 1,5-dicarba-closo-pentaborane(5) are examined theoretically using the gaussian 98 set of quantum chemistry codes. All normal modes were successfully assigned to one of six types of motion predicted by a group theoretical an...

Reaction of [W(PMe2Ph)3H6] with pentaborane(9) gives nido-2-[W(PMe2Ph)3H2B4H8] (1) as well as nido-2-[W(PMe2Ph)3HB5H10] (2). The crystal structure of (2) has been determined. Compound (2) has a novel metallaborane structure containing an edge-bridging {BH3} group between the tungsten atom and on...

In an attempt to synthesize expanded-cage metallaheteroboranes containing heavier chalcogen atoms, the reaction of diruthenaborane analogue of pentaborane(9), nido-[1,2-(Cp*RuH)2B3H7] (1) with phenyl-chalcogenoborates Li[BH3(EPh)] (E = S, Se or Te) was carried out. Thermolysis of nido-1 with Li[...