Two-Dimensional Brickblock Arrangement in Bis-Fused Tetrathiafulvalene Semiconductors

Molecular packing arrangement is a very important factor in the charge carrier mobility of organic semiconductors, but its rational design has not been established as yet. Two-dimensional (2D) lamellar packing is an advantageous arrangement for high charge mobility, but few examples have been reported thus far. Herein we show crystal structures and the electronic properties of newly designed bis-fused tetrathiafulvalene (TTF) semiconductors with hetero substituent groups with distinct electronic effects. Unprecedented 2D lamellar alignment is achieved in a single crystal, where the bis-fused TTF rings interact three dimensionally with face-to-face and side-by-side intermolecular S···S contacts up to a total of 20 sites per π molecule and form graphitelike “brickblock” structure. The charge mobility of a single crystal is as high as 0.78 cm² V^–1s^–1. Systematic investigations of the semiconductors reveal a key role of intramolecular S···O interaction between a bis-fused TTF ring and a methoxycarbonyl group in controlling efficient arrangement, leading to high mobility

Two-Dimensional Brickblock Arrangement in Bis-Fused Tetrathiafulvalene Semiconductors

Molecular packing arrangement is a very important factor in the charge carrier mobility of organic semiconductors, but its rational design has not been established as yet. Two-dimensional (2D) lamellar packing is an advantageous arrangement for high charge mobility, but few examples have been reported thus far. Herein we show crystal structures and the electronic properties of newly designed bis-fused tetrathiafulvalene (TTF) semiconductors with hetero substituent groups with distinct electronic effects. Unprecedented 2D lamellar alignment is achieved in a single crystal, where the bis-fused TTF rings interact three dimensionally with face-to-face and side-by-side intermolecular S···S contacts up to a total of 20 sites per π molecule and form graphitelike “brickblock” structure. The charge mobility of a single crystal is as high as 0.78 cm² V^–1s^–1. Systematic investigations of the semiconductors reveal a key role of intramolecular S···O interaction between a bis-fused TTF ring and a methoxycarbonyl group in controlling efficient arrangement, leading to high mobility

Two-Dimensional Brickblock Arrangement in Bis-Fused Tetrathiafulvalene Semiconductors

Molecular packing arrangement is a very important factor in the charge carrier mobility of organic semiconductors, but its rational design has not been established as yet. Two-dimensional (2D) lamellar packing is an advantageous arrangement for high charge mobility, but few examples have been reported thus far. Herein we show crystal structures and the electronic properties of newly designed bis-fused tetrathiafulvalene (TTF) semiconductors with hetero substituent groups with distinct electronic effects. Unprecedented 2D lamellar alignment is achieved in a single crystal, where the bis-fused TTF rings interact three dimensionally with face-to-face and side-by-side intermolecular S···S contacts up to a total of 20 sites per π molecule and form graphitelike “brickblock” structure. The charge mobility of a single crystal is as high as 0.78 cm² V^–1s^–1. Systematic investigations of the semiconductors reveal a key role of intramolecular S···O interaction between a bis-fused TTF ring and a methoxycarbonyl group in controlling efficient arrangement, leading to high mobility

Ni–Pd Catalyzed Cyclization of Sulfanyl 1,6-Diynes: Synthesis of 1′‑Homonucleoside Analogues

The Ni–Pd catalyzed addition–cyclization of sulfanyl 1,6-diynes <b>2</b>–<b>9</b> with nucleobases is described. The reactions of <i>N</i>-tethered 1,6-diynes with <i>N</i>³-benzoylthymine, <i>N</i>⁴,<i>N</i>⁴-bis­(Boc)­cytosine, <i>N</i>³-benzoyluracil and <i>N</i>⁶,<i>N</i>⁶-bis­(Boc)­adenine exclusively afforded the pyrrolylmethyl and furylmethyl nucleotides in good yields. Deprotection of nucleobases was completed by treatment with acids or bases. Furthermore, the reactions of pyrroles and furans with nucleophiles such as alkoxides and amines underwent detosylation and conversion to the alkoxymethyl- and arylaminomethyl-pyrroles and furans in good yields

Use of a Compact Tripodal Tris(bipyridine) Ligand to Stabilize a Single-Metal-Centered Chirality: Stereoselective Coordination of Iron(II) and Ruthenium(II) on a Semirigid Hexapeptide Macrocycle

Fe­(II)-coordinating hexapeptides containing three 2,2′-bipyridine moieties as side chains were designed and synthesized. A cyclic hexapeptide having three [(2,2′-bipyridin)-5-yl]-d-alanine (d-Bpa5) residues, in which d-Bpa5 and Gly are alternately arranged with 3-fold rotational symmetry, coordinated with Fe­(II) to form a 1:1 octahedral Fe­(II)–peptide complex with a single <i>facial</i>-Λ configuration of the metal-centered chirality. NMR spectroscopy and molecular dynamics simulations revealed that the Fe­(II)–peptide complex has an apparent <i>C</i>₃-symmetric conformations on the NMR time scale, while the peptide backbone is subject to dynamic conformational exchange between three asymmetric β/γ conformations and one <i>C</i>₃-symmetric γ/γ/γ conformation. The semirigid cyclic hexapeptide preferentially arranged these conformations of the small octahedral Fe­(II)–bipyridine complex, as well as the Ru­(II) congener, to underpin the single configuration of the metal-centered chirality

The relations in investments strategies and the capital market efficiency hyphotesis: a study in São Paulo Stock Exchange.

Um dos fundamentos das Finanças, a partir da segunda metade do século 20, é a hipótese de eficiência de mercado. Num Mercado Eficiente, as informações sobre o ativo são transferidas para os preços de modo que o preço do ativo reflete toda informação disponível. Assim, o retorno desse ativo está baseado no nível de risco associado. Esse estudo examina carteiras de ações formadas com base em diferentes critérios e acompanha o retorno produzido no período, verificando as estratégias de investimento que provocam os melhores resultados, ou seja, quais as estratégias vencedoras tomando-se como base uma determinada variável fundamentalista. O resultado obtido poderá confirmar a hipótese de racionalidade do mercado. O trabalho é baseado no retorno apresentado pelas ações no mercado brasileiro no período de 1993 até 2003.Modern Finance is established based in Market Efficiency Hyphotesis, an important concept widely accepted since1950´s. A market in which prices at any time refect all information available is considered efficient. In the present study we built portfolio as per some estrategies for selecting stocks based in past return just to verify winners strategies that can confirm the market efficiency hyphotesis. We followed the return based in stocks from 1993 to 2003 in São Paulo Stock Exchange

Structure–Activity Relationship Study of Cyclic Pentapeptide Ligands for Atypical Chemokine Receptor 3 (ACKR3)

The atypical chemokine receptor 3 (ACKR3)/CXC chemokine receptor 7 (CXCR7) recognizes stromal cell-derived factor 1 (SDF-1)/CXCL12 and is involved in a number of physiological and pathological processes. Here, we investigated the SAR of the component amino acids in an ACKR3-selective ligand, FC313 [<i>cyclo</i>(-d-Tyr-l-Arg-l-MeArg-l-Nal­(2)-l-Pro-)], for the development of highly active ACKR3 ligands. Notably, modification at the l-Pro position with a bulky hydrophobic side chain led to improved bioactivity toward ACKR3

Structure–Activity Relationship Study of Cyclic Pentapeptide Ligands for Atypical Chemokine Receptor 3 (ACKR3)

The atypical chemokine receptor 3 (ACKR3)/CXC chemokine receptor 7 (CXCR7) recognizes stromal cell-derived factor 1 (SDF-1)/CXCL12 and is involved in a number of physiological and pathological processes. Here, we investigated the SAR of the component amino acids in an ACKR3-selective ligand, FC313 [<i>cyclo</i>(-d-Tyr-l-Arg-l-MeArg-l-Nal­(2)-l-Pro-)], for the development of highly active ACKR3 ligands. Notably, modification at the l-Pro position with a bulky hydrophobic side chain led to improved bioactivity toward ACKR3

Alternative <i>in vivo</i> AGE synthesis routes.

<p>Reducing sugars, such as glucose, fructose, and glyceraldehyde, are known to react non-enzymatically with the amino groups of proteins to form reversible Schiff bases and Amadori/Heyns products. These early glycation products undergo further complex reactions such as rearrangement, dehydration, and condensation to become irreversibly cross-linked heterogeneous fluorescent derivatives, termed AGEs. Glu-AGEs, glucose-derived AGEs; Fru-AGEs, fructose-derived AGEs; Glycer-AGEs, glyceraldehyde-derived AGEs; Glycol-AGEs, glycolaldehyde-derived AGEs; MGO-AGEs, methylglyoxal-derived AGEs; GO-AGEs, glyoxal-derived AGEs; 3-DG-AGEs, 3-deoxyglucosone-derived AGEs; CML, <i>N</i>^<i>ε</i>-(carboxymethyl)lysine; P-NH₂, free amino residue of protein; GOLD, GO-lysine dimer; GA-pyridine, 3-hydroxy-4-hydroxymethyl-1-(5-carboxypentyl) pyridinium cation; DOLD, 3-DG-lysine dimer; CEL, <i>N</i>^<i>ε</i>-(carboxyethyl)lysine; MOLD, MGO-lysine dimer; GLAP, glyceraldehyde-derived pyridinium compound.</p

Mean concentrations of various AGEs in commonly consumed foods.

<p>Food items were classified according to the Standard Tables of Food Composition (5th revised and enlarged edition, 2009). The mean concentrations of four kinds of AGEs (Glu-AGEs, Fru-AGEs, CML, and Glycer-AGEs) in each food item are expressed as AGE units (U) per meal and are based on the standard servings consumed by average individuals in Japan.</p