IL-17 may play an important role in the inflammatory response to H pylori colonization, and may ultimately influence the outcome of H pylori-associated diseases that arise within the context of gastritis.

On the basis of Woodward-Hoffmann frontier molecular orbital interactions and steric interactions between dienes and dienophiles during the formation of [2+4] pericyclic transition states, endo/exo selectivity in the Diels-Alder reaction strongly depends on the substrates.[1] Therefore, it is quite difficult to control both enantioselectivity [2] and anomalous endo/exo selectivity by conventional chiral catalysts, which can discriminate only the enantiofaces of the dienophiles. For example, in the reaction between cyclopentadiene (1) and acrolein (2 a), an endo preference is observed with regard to second-order orbital interactions without significant steric interactions [Eq. (1)]. In sharp contrast, in the reaction between 1 and an a-substituted acrolein (R ¼ 6 H), such as methacrolein (2 b), an exo preference is observed with regard to steric interactions between the methylene moiety of 1 and the substituent R at the a position of the dienophile [Eq. (2)]. Therefore, enantiomerically enriched endo-3 a and exo-3 b have been synthesized by using many conventional chiral catalysts.[2] Moreover, thermodynamically more stable and enantiomerically enriched exo-3 a can be generated by the epimerization of endo-3 a [Eq. (1)]. Alternatively, catalystinduced anomalous exo-selective Diels-Alder reactions that contravene the endo rule have been performed by Yamamoto and co-workers [3] in a non-asymmetric manner, and later by Maruoka and co-workers, [4] Sibi et al., [5] and Hayashi et al. [6] in an asymmetric manner. In contrast, enantiomerically enriched endo-3 b with a quaternary carbon center can not be generated by the epimerization of exo-3 b or by other known synthetic methods [Eq. (2)]. To the best of our knowledge, no examples of catalyst-induced anomalous endo-selective enantioselective Diels-Alder reactions with a-substituted acroleins have been reported to date. To address this major yet unexplored subject, catalysts must discriminate chiral transition-state structures by precisely recognizing the re or si face of dienophiles, and the endo or exo approach of dienes, thus, the rational design of conformationally flexible chiral supramolecular catalysts, such as enzymes, is necessary. [7] As such, conformationally rigid metal-organic frameworks (MOFs) are not suitable as artificial enzymes because they have few induced-fit properties to adapt dynamics in transition states. [8] A chiral supramolecular catalyst (4 a) was readily prepared in situ from three components, which included 10 mol % of chiral (R)-3,3'-bis(5,5-dimethyl-2-oxido-1,3,2-dioxaphosphorinan-2-yl)-BINOL (5 a; BINOL = 1,1'-bi(2-naphthol)), [9] 10 mol % of 3,5-bis(trifluoromethyl)phenylboronic acid (6 a), and 20 mol % of tris(pentafluorophenyl)borane (7), by taking advantage of the typical preparation of boron BINOLates [10] (Scheme 1). Intermolecular acid-base coordinate bonds in the two P=O···B(C 6 F 5 ) 3 moieties [11] are critical for the design of conformationally flexible complex 4 a; compound 7 acts as a bulky functional group to form a ch...

An efficient aerobic linear allylic C—H amination reaction (LAA) is reported under Pd(II)/bis-sulfoxide/Brønsted base catalysis. The reaction operates under preparative, operationally simple conditions (1 equiv. olefin, 1 atm. O2 or air), with reduced Pd(II)/bis-sulfoxide catalyst loadings while providing higher turnovers and product yields than systems employing stoichiometric benzoquinone (BQ) as the terminal oxidant. Palladium(II)/benzoquinone π-acidic interactions have been invoked in various catalytic processes and are often considered beneficial in promoting reductive functionalizations. When such electrophilic activation for functionalization is not needed, however, benzoquinone at high concentrations may compete with crucial ligand (bis-sulfoxide) binding and inhibit catalysis. Kinetic studies reveal an inverse relationship between the reaction rate and the concentration of BQ, suggesting that benzoquinone is acting as a ligand for Pd(II) which results in an inhibitory effect on catalysis.

H. pylori-infected ITP patients have a corpus-predominant pattern of gastritis but the virulence profile of their strains does not differ from that of ulcer or NUD patients. Eradication of H. pylori infection is a good therapeutic option for some patients with chronic ITP, especially for those who develop ITP in older age.

The Diels–Alder reaction, which is a traditional [4 + 2] cycloaddition with two carbon–carbon bond formations, is one of the most powerful tools to synthesize versatile and unique six-membered rings. We show that chiral supramolecular U-shaped boron Lewis acid catalysts promote the unprecedented multiselective Diels–Alder reaction of propargyl aldehyde with cyclic dienes. Independent from the substrate control, enantio-, endo/exo-, π-facial-, regio-, site-, and substrate-selectivities could be controlled by the present U-shaped catalysts. The obtained reaction products could access the concise synthesis of chiral diene ligands and a key intermediate of (+)-sarkomycin. The results presented here might partially contribute to the development of artificial enzyme-like supramolecular catalysts for multiselective reactions, which will be able to target organic compounds that have thus far eluded synthesis.