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3Z,5E-Octa-3,5-diene-1,3,4-tricarboxylic acid-3,4-anhydride (ODTAA, 1) was isolated from Paecilomyces sp. FKI-6801 for its selective IMP-1 MBL inhibitory activity. The first total synthesis of 1 from the commercially available compound was achieved in 9 steps with 28% overall yield. Introduction of catechol to the maleic anhydride of 1 improved the IC

A simple and rapid analytical method was developed for determination of four biogenic amines [histamine (Him), cadaverine (Cad), tyramine (Tym), 2-phenylethylamine (Pea)] in fish and fish products. This method uses a new derivatization reagent, 2,4,6-triethyl-3,5-dimethyl pyrylium trifluoromethanesulfonate (Py-Tag). The four biogenic amines in the samples were extracted with trichloroacetic acid. The diluted extract was derivatized with Py-Tag (15 min at 50°C) and then subjected to liquid chromatography-tandem mass spectrometry (LC-MS/MS). The limits of quantification for the method were 2 mg/kg for Him, Tym, and Pea and 10 mg/kg for Cad. The matrix effects derived from the tested fish and fish products were negligible in the LC-MS/MS analysis. The impact of the sample matrices on the Py-Tag derivatization was also negligible. The trueness and repeatability of the method were assessed by performing replicate analyses (n = 5) of five samples of fish and fish products, each spiked with the four biogenic amines at three different concentration levels. Analysis of the samples found 87%-104% of the spiked concentrations and the relative standard deviations were6.1%. A reference sample and quality control canned fish samples were analyzed by the method, and the concentrations of the Him were within acceptable limits. The developed method was successfully used to determine concentrations of the four biogenic amines in 48 fish and fish products on the Japanese market. The developed method does not require cleanup using a solid-phase extraction column or similar, and the derivatization reaction time was only 15 min. The results suggested that the present method is reliable and suitable for rapid analysis of the four biogenic amines in fish and fish products.

Site specific introduction of the polar hydrophobic trifluoromethyl-λ6-tetrafluorosulfanyl (CF3SF4) group can effectively control the secondary structure of a heptapeptide, the minimum repeat unit of an α-helix. The structural influence of CF3SF4-containing amino acid on the heptapeptide was established using NMR methods.

We describe the preparation of a cyclic hemiacetal-lactone 6, which is a key intermediate in the total synthesis of Aurodox (1) and also a degradation product of aurodox. The bicyclic core of 6 was obtained by lactonization and hemiacetalization after stereo-selective epoxidation at late stage. The construction of olefins utilized a Wittig reaction and a Horner-Wadsworth-Emmons reaction using d -pantolactone (14).

The addition of InBr3 to the oxidative Sonogashira cross-coupling reaction of 2-ethynylaniline with (E)-trimethyl(3,3,3-trifluoroprop-1-enyl)silane led to a dramatic increase in the reactivity to afford the corresponding 1,3-enynes bearing a trifluoromethyl group on their terminal sp(2) carbon. The subsequent cyclization of these 1,3-enynes under palladium catalysis provides access to the corresponding indoles bearing a 3,3,3-trifluoroprop-1-enyl group at their 2-position.

Oxidative Sonogashira cross-coupling reactions of (E)-trimethyl(3,3,3-trifluoroprop-1-enyl)silane with arylacetylene were achieved using silver fluoride and a palladium catalyst, to afford high yields of various 1,3-enynes with a CF3 group on the terminal sp(2) carbon. Silver fluoride promoted C-Si bond dissociation and oxidation of palladium, enabling catalytic use of palladium.

The Hiyama cross-coupling reaction of (E)-trimethyl(3,3,3-trifluoroprop-1-enyl)silane (1) with 2-iodoaniline (2) proceeded without any protection of the amino group. The coordination of copper(II) fluoride to 2,2'-bipyridyl provided the fluoride source required to trigger this reaction, affording (E)-2-(3,3,3-trifluoroprop-1-enyl)aniline (3). In the presence of a stoichiometric amount of [Cu(OTf)]2·C6H6, the treatment of 3 with an aryl aldehyde at 200 °C provided the 2-aryl-3-trifluoromethylquinoline (4) via the oxidative cyclization of an in situ-generated imine substructure.

(E)-trimethyl-(3,3,3-trifluoroprop-1-enyl)silane (1) was synthesized as a reagent for use in Hiyama cross-coupling reactions for the production of β-trifluoromethylstyrene derivatives. Cross-coupling of 1 with electronically diverse aryl iodides was achieved by treatment with CsF in the presence of catalytic amounts of palladium to afford the desired products in moderate to good yields.

Adsorption isotherm measurements were carried out for N2 on the basal plane of graphite held at a temperature 77 K and preplated with n-alkanes or conjugated species such as mono-substituted benzenes, anthracene, 9,10-dimethylanthracene, and phthalocyanine copper. The isotherm step arising from the fluid–solid phase transition has been found to be abnormally depressed by the conjugated species, whereas the n-alkanes have no effect on the phase behavior of N2. A similar phase transition for CO has also been found to be depressed by preadsorbed phthalocyanine copper. It is suggested that a small amount of these conjugated species dissolved in N2 and CO locally induce the 3×3 commensurate structure of N2 and CO to increase the molecular density in the fluid phase and, therefore, to depress abnormally the fluid–solid phase transition of N2 and CO.

The cyclocondensation reaction to yield quinolines (V) is only suitable for aromatic aldehydes (IV), but not aliphatic aldehydes.

Starting from commercially available materials, a gram-scale preparation of the key compound (II) is described in three steps with an overall yield of 74%.