Possible bi-stable structures of pyrenebutanoic acid-linked protein molecules adsorbed on graphene: theoretical study

• Yasuhiro Oishi,
• Motoharu Kitatani and
• Koichi Kusakabe

Beilstein J. Org. Chem. 2024, 20, 570–577, doi:10.3762/bjoc.20.49

• . A substitution effect that does not effectively change the potential energy surface is isotopic substitution. In fact, the adiabatic potential surface defined for a hypothetical motion at the absolute zero is not changed by a change in nuclear mass. Even in density functional theory calculations

Syntheses of novel pyridine-based low-molecular-weight luminogens possessing aggregation-induced emission enhancement (AIEE) properties

• Masayori Hagimori,
• Tatsusada Yoshida,
• Yasuhisa Nishimura,
• Yukiko Ogawa and
• Keitaro Tanaka

Beilstein J. Org. Chem. 2022, 18, 580–587, doi:10.3762/bjoc.18.60

• thus induced increased fluorescence. The N-methyl-4-((pyridin-2-yl)amino)-substituted maleimides 4a–e comprised an A–D–A system, which exhibited an obvious substitution effect on the fluorescence properties (Figures S18 and S19 in Supporting Information File 1). Although the unsubstituted compound 4a

Regioselectively α- and β-alkynylated BODIPY dyes via gold(I)-catalyzed direct C–H functionalization and their photophysical properties

• Takahide Shimada,
• Shigeki Mori,
• Masatoshi Ishida and
• Hiroyuki Furuta

Beilstein J. Org. Chem. 2020, 16, 587–595, doi:10.3762/bjoc.16.53

• estimated to be 2.30, 2,14, 2.35, and 2.21 V, respectively, which is consistent with the calculated HOMO–LUMO energy gaps (vide infra, Figure S24, Supporting Information File 1). Theoretical calculations To gain insight into the substitution effect on the electronic properties of the BODIPY derivatives

Synthesis, liquid crystalline behaviour and structure–property relationships of 1,3-bis(5-substituted-1,3,4-oxadiazol-2-yl)benzenes

• Afef Mabrouki,
• Malek Fouzai,
• Armand Soldera,
• Abdelkader Kriaa and
• Ahmed Hedhli

Beilstein J. Org. Chem. 2020, 16, 149–158, doi:10.3762/bjoc.16.17

• -substitution effect has been well studied, especially in the fluoroaromatic derivatives [11][12][13]. Additionally, the mesomorphic properties of liquid crystals depend strongly on the nature of the terminal chains that are present. A terminal perfluorocarbon chain present in a LC molecule causes stiffening

A combinatorial approach to improving the performance of azoarene photoswitches

• Joaquin Calbo,
• Aditya R. Thawani,
• Rosina S. L. Gibson,
• Andrew J. P. White and
• Matthew J. Fuchter

Beilstein J. Org. Chem. 2019, 15, 2753–2764, doi:10.3762/bjoc.15.266

• ). In order to confirm our predictions of the ortho-substitution effect on the thermal Z–E isomerization process, photoswitches 4pzMe-F2, 4pzMe-Cl2, 4pzMe-OMe2 and 4pzH-F2 were synthesized (see Supporting Information File 1). Following irradiation to the PSS (see further details below), the thermal Z–E

A golden opportunity: benzofuranone modifications of aurones and their influence on optical properties, toxicity, and potential as dyes

• Joza Schmitt and
• Scott T. Handy

Beilstein J. Org. Chem. 2019, 15, 1781–1785, doi:10.3762/bjoc.15.171

• . In this study, the influence of substitution in the benzofuranone ring on the UV–vis spectrum is explored, as well as an initial screening of their toxicity and a qualitative preliminary study of their potential to act as fabric dyes. Keywords: aurone; dyeing; dyes; substitution effect; toxicity; UV

[3 + 2]-Cycloaddition reaction of sydnones with alkynes

• Veronika Hladíková,
• Jiří Váňa and
• Jiří Hanusek

Beilstein J. Org. Chem. 2018, 14, 1317–1348, doi:10.3762/bjoc.14.113

• slightly favored. The same trend [8] can be seen from the substitution effect in position 4 of the starting 3-phenylsydnone when reacted with methyl propiolate (Table 4, entries 6, 7, 23–26) but almost no influence is observed for reactions with phenylacetylene (Table 4, entries 3, 4, 69, 91). Generally

Spectral and DFT studies of anion bound organic receptors: Time dependent studies and logic gate applications

• Srikala Pangannaya,
• Neethu Padinchare Purayil,
• Shweta Dabhi,
• Venu Mankad,
• Prafulla K. Jha,
• Satyam Shinde and
• Darshak R. Trivedi

Beilstein J. Org. Chem. 2017, 13, 222–238, doi:10.3762/bjoc.13.25

• an “INHIBIT” logic gate. The “INHIBIT” logic gate and truth table is represented in Figure 23 and Table 3. Conclusion Two new organic receptors exhibiting a positional substitution effect have been designed, synthesized and characterized. They were shown to allow the qualitative and quantitative

Facile synthesis of 1H-imidazo[1,2-b]pyrazoles via a sequential one-pot synthetic approach

• András Demjén,
• Márió Gyuris,
• János Wölfling,
• László G. Puskás and
• Iván Kanizsai

Beilstein J. Org. Chem. 2014, 10, 2338–2344, doi:10.3762/bjoc.10.243

• , limited substitution effect correlations could be established by employing aromatic aldehydes 2a–h. The introduction of electron-donating substituents such as 4-Me or 2,4,6-tri-OMe (derived from aldehydes 2a and 2h) resulted in similar conversions as for 2b, whereas the presence of two electron

Substitution effect and effect of axle’s flexibility at (pseudo-)rotaxanes

• Friedrich Malberg,
• Jan Gerit Brandenburg,
• Werner Reckien,
• Oldamur Hollóczki,
• Stefan Grimme and
• Barbara Kirchner

Beilstein J. Org. Chem. 2014, 10, 1299–1307, doi:10.3762/bjoc.10.131

• benzyl group (Figure 1 bottom), only four hydrogen bonds can be formed between the subunits through wheel–NH···O=C-axle interactions. At the two different axles with single and double bond, the phenyl groups of the axle will be substituted symmetrically in order to investigate the substitution effect

• to many benchmark calculations (see, e.g., [49][51][56]), both functionals perform very similar for non-covalent interaction (TPSS-D3 being even somewhat better for hydrogen bonding), which supports the above conclusion. Substitution effect The interaction energies in Table 2 show that the more

Synthesis and biological activities of the respiratory chain inhibitor aurachin D and new ring versus chain analogues

• Xu-Wen Li,
• Jennifer Herrmann,
• Yi Zang,
• Philippe Grellier,
• Soizic Prado,
• Rolf Müller and
• Bastien Nay

Beilstein J. Org. Chem. 2013, 9, 1551–1558, doi:10.3762/bjoc.9.176

• activity of the 2,3-dimethylquinolone core (compared to 11). Due to the lack of the farnesyl chain, this comparison of the quinolone substitution effect yet diverges from previous observations showing an approximately 200-fold higher activity of aurachin C (3) compared to aurachin D (4) (which however

Ring-alkyl connecting group effect on mesogenic properties of p-carborane derivatives and their hydrocarbon analogues

• Aleksandra Jankowiak,
• Piotr Kaszynski,
• William R. Tilford,
• Kiminori Ohta,
• Adam Januszko,
• Takashi Nagamine and
• Yasuyuki Endo

Beilstein J. Org. Chem. 2009, 5, No. 83, doi:10.3762/bjoc.5.83

• increase of the TNI by about 30 K and 45 K, respectively, for all structural units A–D. The only exception is the pair 14D[6]/16D[6] for which the change in TNI is only 16 K. The larger change of TNI for pairs 17/20 than for 14[6]/16[6] is consistent with attenuation of the substitution effect by the