We have successfully achieved efficient recognition of mismatched sites in double-stranded DNA through the formation of an invasion complex by using partially noncomplementary peptide nucleic acids (PNAs). Owing to mismatches between 2 PNAs used for invasion, the undesired PNA/PNA duplex, which inhibits invasion complex formation, was destabilized. This approach overcame an inherent challenge in PNA invasion, in particular, undesired PNA/PNA duplex formation resulting from PNA complementarity, thereby enhancing overall invasion efficiency.

Camphor and related monoterpenoid natural products have served as versatile "chiral pool" materials in organic chemistry for over half a century. Historically, many researchers have used a variety of transformations involving orchestrated rearrangements of the bornane skeleton to functionalize the camphor framework, expanding the utility of this chiral building block. Recent developments in C-H functionalization methodologies provide myriad opportunities to derivatize the camphor framework in a selective and predictable fashion. In this review, a short summary of the methods for functionalization of the camphor scaffold using rearrangement chemistry is provided followed by a discussion of emerging methods for directed C-H functionalizations that provide diverse new ways to derivatize the camphor framework.

Allenoates are versatile reagents that can be used for numerous (formal) cycloaddition reactions under (chiral) Lewis base catalysis. Most commonly, the catalysts of choice are phosphines, amines, and -heterocyclic carbenes. We have recently established the use of readily available chiral isochalcogenoureas as catalysts for asymmetric (4 + 2)-heterocycloadditions of allenoates with various vinylogous acceptors. This represents a complementary approach for allenoate activation and gives access to various highly functionalized chiral dihydropyrans with good to excellent enantioselectivities and diastereoselectivities.

CsoR/RcnR transcriptional repressors adopt a disc-shaped, all α-helical dimer of dimers tetrameric architecture, with a four-helix bundle the key structural feature of the dimer. Individual members of this large family of repressors coordinate Cu(I) or Ni(II)/Co(II) or perform cysteine sulfur chemistry in mitigating the effects of metal or metabolite toxicity, respectively. Here we highlight recent insights into the functional diversity of this fascinating family of repressors.

Enol ethers, β-dicarbonyl compounds and the Mn(III) reagent MnO(OAc) react under mild conditions to form 1-alkoxy-1.2-dihydrofurans in good (70-98%) yields. The latter are readily converted to furans by acid-catalyzed elimination of ROH.

Under the conditions of ruthenium catalyzed transfer hydrogenation employing isopropanol as terminal reductant, π-unsaturated compounds (1,3-dienes, allenes, 1,3-enynes and alkynes) reductively couple to aldehydes to furnish products of carbonyl addition. In the absence of isopropanol, π-unsaturated compounds couple directly from the alcohol oxidation level to form identical products of carbonyl addition. Such "alcohol-unsaturate C-C couplings" enable carbonyl allylation, propargylation and vinylation from the alcohol oxidation level in the absence of stoichiometric organometallic reagents or metallic reductants. Thus, direct catalytic C-H functionalization of alcohols at the carbinol carbon is achieved.

Pd(II)-catalyzed cross-coupling of -C-H bonds in benzoic acid and phenylacetic acid amides with alkyl-, aryl- and vinyl-boron reagents have been achieved Pd(II)/Pd(0) catalysis, demonstrating the unprecedented versatility of C-H activation reactions.

A direct palladium-catalyzed highly regioselective C-3 arylation of imidazo[1,5-]pyridine with aryl bromides has been developed. This reaction is quite general with respect to the aryl or hetaryl bromide.

Heme is involved in signal transduction by either acting as a cofactor of heme-based gas/redox sensors or binding reversely to heme-responsive proteins. Bacteria respond to low concentrations of nitric oxide (NO) to modulate group behaviors such as biofilms through the well-characterized H-NOX family and the newly discovered heme sensor protein NosP. NosP shares functional similarities with H-NOX as a heme-based NO sensor; both regulate two-component systems and/or cyclic-di-GMP metabolizing enzymes, playing roles in processes such as quorum sensing and biofilm regulation. Interestingly, aside from its role in NO signaling, recent studies suggest that NosP may also sense labile heme. In this , we briefly summarize H-NOX-dependent NO signaling in bacteria, then focus on recent advances in NosP-mediated NO signaling and labile heme sensing.