Tetraaryl‐Substituted Benzo[1,2‐b:4,5‐b′]dipyrroles: Synthesis,Properties, and Applications to Hole‐Injection Materials in OLED Devices

Yes, HIMs can! A series of 2,3,6,7‐tetraarylbenzo[1,2‐b:4,5‐b′]dipyrroles (BDPs) were synthesized using zinc‐mediated double cyclization. Organic light‐emitting diodes consisting of BDP:PPB as a hole‐injection layer could be driven at a lower voltage than a PEDOT:PSS‐based device. Correlation of the IP values with the driving voltage shed some light on the mechanism of hole‐injection processes.

     

Two‐Step Synthesis of 1,3‐Disubstituted 3,4‐Dihydro‐4‐thioxoquinazolin‐2(1H)‐ones from 1‐Bromo‐2‐fluorobenzenes

An efficient synthesis of 3‐alkyl‐3,4‐dihydro‐4‐thioxobenzoquinazolin‐2(1H)‐ones 3 has been accomplished in two steps and in satisfactory yields from 1‐bromo‐2‐fluorobenzenes 1 . Thus, the reaction of 1‐fluoro‐2‐lithiobenzenes, generated by the Br/Li exchange between 1 and BuLi, with alkyl isothiocyanates, gives N‐alkyl‐2‐fluorobenzothioamides 2 , which, in turn, react with a series of isocyanates in the presence of NaH to give the desired products 3 .     

Cell-Penetrating Peptide–Peptide Nucleic Acid Conjugates as a Tool for Protein Functional Elucidation in the Native Bacterium

Approximately 30% or more of the total proteins annotated from sequenced bacteria genomes are annotated as hypothetical or uncharacterized proteins. However, elucidation on the function of these proteins is hindered by the lack of simple and rapid screening methods, particularly with novel or hard-to-transform bacteria. In this report, we employed cell-penetrating peptide (CPP) –peptide nucleotide acid (PNA) conjugates to elucidate the function of such uncharacterized proteins in vivo within the native bacterium. Paenibacillus, a hard-to-transform bacterial genus, was used as a model. Two hypothetical genes showing amino acid sequence similarity to ι-carrageenases, termed cgiA and cgiB, were identified from the draft genome of Paenibacillus sp. strain YYML68, and CPP–PNA probes targeting the mRNA of the acyl carrier protein gene, acpP, and the two ι-carrageenase candidate genes were synthesized. Upon direct incubation of CPP–PNA targeting the mRNA of the acpP gene, we successfully observed growth inhibition of strain YYML68 in a concentration-dependent manner. Similarly, both the function of the candidate ι-carrageenases were also inhibited using our CPP–PNA probes allowing for the confirmation and characterization of these hypothetical proteins. In summary, we believe that CPP–PNA conjugates can serve as a simple and efficient alternative approach to characterize proteins in the native bacterium.     

Depth measurement of a blood flow region based on speckle decorrelation

Optical Review - Laser speckle technique is a useful means for imaging blood flow in living bodies and, it has been utilized for analyzing the condition of living bodies or the health state....     

Synthesis of chiral mesoporous silica and its potential application to asymmetric separation

Chiral mesoporous silica (CMS) has been successfully synthesized in the presence of basic amino acids; the use of basic amino acids in combination with the chiral anionic surfactant is advantageous for the formation of CMS in terms of uniformity in the twisted morphology. We first demonstrate that thus obtained chiral mesoporous silicas can be used for the enantioselective separation of racemic compounds; the helical rod-shaped CMS is found to be capable of asymmetric separation of racemic N-trifluoroacetylalanine ethyl ester (CF₃CO-Ala-OEt). The left handedness-rich CMS shows asymmetric preferential adsorption of the L isomer and vice versa.     

Possible new route for the production of C60 by ultrasound

The production of C60 by ultrasonic irradiation of liquid benzene has been studied. After irradiating 150 ml of liquid benzene for 1 h (600 W, 20 kHz), approximately 1 microgram of C60 is produced.