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The mechanism of the deactivation and regeneration of PtSn intermetallic compound nanoparticle (iNP) catalysts was studied by in situ TEM investigation. Our study reveals the reversible dynamic structural transition of the iNPs during deactivation and regeneration, which provides a direct correlation between the atomic structure and the catalytic activity of the iNPs. [ABSTRACT FROM AUTHOR]

A cinchona alkaloid squaramide promoted enantioselective [4+2] cyclization between hydroxymaleimides and ortho-hydroxyphenyl p-QMs has been disclosed, and a wide range of chiral hemiketals containing chromane and succinimide frameworks with two adjacent quaternary stereogenic centers have been prepared for the first time with excellent results (up to 99% yield, up to 99 : 1 dr, up to >99% ee) under mild conditions. [ABSTRACT FROM AUTHOR]

A novel DNA nanotetrad mediated crosslinking catalytic hairpin assembly (CCHA) is reported to generate clumps of cross-linked mesh products for high-contrast and simultaneous imaging of multiple mRNAs in living cells. [ABSTRACT FROM AUTHOR]

Natural hollow fibers were used as templates to in situ produce thin Cs4PbX6 nanosheets on the inner walls, forming luminescent fibers that integrated the advantages of the large length of fibers and the emission tunability of perovskites, and exhibited great robustness as well for multiple applications like warning signs, anti-counterfeiting and fashion. [ABSTRACT FROM AUTHOR]

We synthesized a series of acridone derivatives for specific binding ligands of i-motifs. Subsequent evaluations showed that B19 could selectively bind to and stabilize the c-myc promoter i-motif without significant binding to the G-quadruplex and duplex DNA. This caused down-regulation of c-myc transcription and expression, resulting in tumor cell apoptosis. [ABSTRACT FROM AUTHOR]

Ozonolysis of aromatic abietane (+)-carnosic acid (4) is used to create an important intermediate in an enantiomerically pure form, resulting in a simple, concise, readily scalable, and asymmetric synthesis of (−)-antrocin (1). This strategy not only provides an efficient approach to (−)-antrocin (1) synthesis but can also be readily adopted for the syntheses of optically pure (+)-asperolide C (2) and (−)-trans-ozic acid (3) from the naturally abundant aromatic abietanes (+)-podocarpic acid (5) and (+)-dehydroabietic acid (6). The strategy presented here is an example of the use of naturally occurring aromatic abietanes as a chiral pool and offers an account of the asymmetric synthesis of terpenoids. [ABSTRACT FROM AUTHOR]

The first bidentate directing group assisted highly selective meta arylation of β-arylethylamine derivatives via palladium/norbornene catalysis is reported, and the range of aryl iodides for the oxalyl amide assisted meta-selective arylation reactions is broadest yet reported. This meta arylation also proceeds well with thiophene derivatives, giving the corresponding products in satisfactory yields. And three-step functionalization of arylethyloxalamide with three different functional groups is successfully performed. [ABSTRACT FROM AUTHOR]

An efficient Pd-catalyzed silylation reaction of benzylic halides with silylboronate is reported. In this reaction, primary and secondary benzylic halides could react well with silylboronates to afford benzylic silanes. This reaction accommodates a broad substrate scope and proceeds smoothly under very mild reaction conditions. The corresponding products could be obtained in moderate to high yields and with stereospecificity. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed intermolecular alkylation of enamides with α-bromo carbonyls was developed. Under mild reaction conditions, various cyclic and acyclic enamides reacted well with α-bromo carbonyls to afford the corresponding multi-substituted alkene products in good yields. The coupling products could be converted into very useful γ-amino acid, δ-amino alcohol, 1,4-dicarbonyl and γ-lactam derivatives. [ABSTRACT FROM AUTHOR]

Cp*Rh(iii)- and Cp*Ir(iii)-catalysed direct C–H arylation with quinone diazides as efficient coupling partners is disclosed. This redox-neutral protocol offers a facile, operationally simple and environmentally benign access to arylated phenols. The reaction represents the first example of Cp*Ir(iii)-catalysed C–H direct arylation reaction. [ABSTRACT FROM AUTHOR]

Two series of novel functionalized polyhydroisoquinoline derivatives have been synthesized via the three-component domino reaction of glutaraldehyde and malononitrile with a series of β-ketoamides under microwave irradiation conditions in the presence of a catalytic amount of Et3N (10 mol%). This reaction represents the first reported process for the facile conversion of a β-ketoamide to a hydroisoquinoline via a C–N bond cleavage reaction without the need for a multistep reaction process. [ABSTRACT FROM AUTHOR]

A series of new octahydrobenzo[b]indeno[1,2,3-de][1,8] naphthyridine and decahydropyrido[2,3,4-gh]phenanthridine derivatives were synthesized via a four-component domino reaction under microwave irradiation. This one-pot transformation, which involved multiple steps and did not require the use of a catalyst, constructed four new C–C bonds, two new C–N bonds, and three new rings, with efficient use of all reactants. [ABSTRACT FROM AUTHOR]

A new switch-on fluorescent probe containing the natural product cryptolepine analogue benzofuroquinolinium moiety (binding scaffold) and a benzothiazole moiety (signalling unit) shows a remarkable fluorescence enhancement selective for the G-quadruplex nucleic acid structure. Binding studies revealed that the highly selective response of the fluorescent probe arises from end-stack binding to G-quadruplex. [ABSTRACT FROM AUTHOR]

An unprecedented cascade Heck–Aldol–Heck reaction was developed to form two C–C single bonds and one CC double bond in one process by a combination of palladium(0) catalysis and aminocatalysis. Various aryl iodides could perform the cascade reaction with readily available propenol and formaldehyde to afford novel (E)-trisubstituted alkenes in 66–81% yields. [ABSTRACT FROM AUTHOR]

An organic crystal has been designed and constructed by the hydrogen-bond-directed self-assembly of TCA and dpyb, which possesses the large honeycomb net with 5.1 × 5.1 nm cavities and a novel interpenetrated n-Borromean linked topology. [ABSTRACT FROM AUTHOR]