492-97-7Relevant articles and documents
Desorption/ionization on self-assembled monolayer surfaces (DIAMS)
Sanguinet,Aleveque,Blanchard,Dias,Levillain,Rondeau
, p. 830 - 833 (2006)
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Receptor- And ligand-based study on novel 2,2′-bithienyl derivatives as non-peptidic AANAT inhibitors
Lepailleur, Alban,Lemaitre, Stephane,Feng, Xiao,Santos, Jana Sopkova-De Oliveira,Delagrange, Philippe,Boutin, Jean,Renard, Pierre,Bureau, Ronard,Rault, Sylvain
, p. 446 - 460 (2010)
Arylalkylamine N-acetyl transferase (serotonin N-acetyl transferase, AANAT) is a critical enzyme in the light-mediated regulation of melatonin production and circadian rythm. With the objective of discovering new chemical entities with inhibitory potencies against AANAT, a medium-throughput screening campaign was performed on a chemolibrary. We found a class of molecules based on a 2,2′-bithienyl scaffold, and compound 1 emerged as a first hit. Herein, we describe our progress from hit discovery and to optimization of this new class of compounds. To complete the study, computational approaches were carried out: a docking study which provided insights into the plausible binding modes of these new AANAT inhibitors and a three-dimensional quantitative structure-activity relationship study that applied comparative molecular field analysis (CoMFA) methodology. Several CoMFA models were developed (variable alignments and options), and the best predictive one yields good statistical results (q2 = 0.744, r2 = 0.891, and s = 0.273). The resulting CoMFA contour maps were used to illustrate the pharmacomodulations relevant to the biological activities in this series of analogs and to design new active inhibitors. This novel series of 2,2′-bithienyl derivatives gives new insights into the design of AANAT inhibitors.
Laser flash photolysis study on the photoinduccd reactions of 3,3′-bridged bithiophenes
Fujitsuka, Mamoru,Sato, Tadatake,Sezaki, Fumiyasu,Tanaka, Kazuyoshi,Watanabe, Akira,Ito, Osamu
, p. 3331 - 3337 (1998)
Photophysical properties and photoinduced reactions of 3,3′-bridged-2,2′-bithiophenes {dithieno[3,2-b:2′,3′-d]-thiophene, 4H-cyclopenta[2,1-b:3,4-b′]dithiophene, and 4H-dithieno[3,2-b;2′,3′-d]pyrrole (DTP)} and 2,2′-bithiophene (BT) were investigated by observing the transient absorption spectra in the visible and near-IR regions using nanosecond laser flash photolysis. Fluorescence quantum yields for the bridged bithiophenes were low compared with that for BT. An especially low quantum yield for DTP in acetonitrile was attributed to an addition reaction with the solvent. The triplet energy of BT was the lowest amongst the examined bithiophenes, indicating some conformational change in the triplet state. Triplet-energy-transfer reactions at diffusion limited rates were confirmed between bithiophenes and triplet-energy donors or acceptors. Photochemical generation of the radical cations of the bithiophenes was confirmed by the transient absorption spectra, which show good correspondence with those observed in γ-ray radiolysis. It was found that the triplet quenching rates of the electron-transfer reactions were small when the Gibbs energy change for the reaction was ≥ -25 kJ mol-1. The observed tendency agreed with the semi-empirical equation of Rehm-Weller. The generated radical cations decay according to a second-order function, indicating deactivation by a back electron-transfer reaction.
Preparation and Reactions of Dichlorodithienogermoles
Ohshita, Joji,Nakamura, Masashi,Ooyama, Yousuke
, p. 5609 - 5614 (2015)
The reaction of 3,3′-dilithiobithiophenes with tetrachlorogermane afforded 4,4-dichlorodithienogermoles, which readily underwent substitution on the central germanium atom. Reactions of a dichlorodithienogermole with LiAlH4, MeLi, Me2NC6H4Li, and C6F5MgBr gave the corresponding Ge-substituted products. Dihydrodithienogermole obtained from the reaction with LiAlH4 was further treated with LDA to give a dimer whose structure was verified by a single-crystal X-ray diffraction (XRD) study. Hydrolysis of dichlorodithienogermoles provided cyclotetragermoxanes. Their optical properties were examined with respect to the UV absorption and fluorescence spectra. It was found that one of the cyclotetragermoxanes responded to a nitorobenzene vapor in the solid state, decreasing the PL intensity.
A novel approach to a one-pot synthesis of unsubstituted oligo(α-thiophenes)
Buzhansky, Ludmila,Feit, Ben-Ami
, p. 7523 - 7525 (2002)
Oligo(α-thiophenes) α-4T and α-8T were prepared by the following one-pot sequential conversions: thiophene (T) → α-2T → α-4T → α-8T. PdCl2-induced coupling of a mono-α-mercuration derivative of each of the n-mers T, α-2T, and α-4T was applied in these conversions.
Copper(I)-catalysed homocoupling of organosilicon compounds: Synthesis of biaryls, dienes and diynes
Kang, Suk-Ku,Kim, Tae-Hyun,Pyun, Sung-Jae
, p. 797 - 798 (1997)
Copper(I) iodide catalyses the homocoupling of aryl-, alkenyl- and alkynyl-substituted chloro- or fluorodimethylsilanes under mild conditions to afford biaryls, dienes and diynes, respectively.
SYNTHESIS OF 5-(3-PYRIDYL)-2,2'-BITHIOPHENE(SENSITIZER)
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Page/Page column 9, (2021/02/05)
Disclosed herein is a novel simple, short process for synthesis of the photosensitizer, 5-(3-pyridyl)-2,2'-bithiophene.
Porphyrin n-pincer pd(Ii)-complexes in water: A base-free and nature-inspired protocol for the oxidative self-coupling of potassium aryltrifluoroborates in open-air
Hanafiah, Marlia M.,Lakkaboyana, Sivarama Krishna,Lakshmidevi, Jangam,Marella, Ravi Kumar,Naidu, Bandameeda Ramesh,Prasad, Sana Siva,Venkateswarlu, Katta
, (2021/09/13)
Metalloporphyrins (and porphyrins) are well known as pigments of life in nature, since representatives of this group include chlorophylls (Mg-porphyrins) and heme (Fe-porphyrins). Hence, the construction of chemistry based on these substances can be based on the imitation of biological systems. Inspired by nature, in this article we present the preparation of five different porphyrin, meso-tetraphenylporphyrin (TPP), meso-tetra(p-anisyl)porphyrin (TpAP), tetra-sodium meso-tetra(p-sulfonatophenyl)porphyrin (TSTpSPP), meso-tetra(m-hydroxyphenyl)porphyrin (TmHPP), and meso-tetra(m-carboxyphenyl)porphyrin (TmCPP) as well as their N-pincer Pd(II)-complexes such as Pd(II)-meso-tetraphenylporphyrin (PdTPP), Pd(II)-meso-tetra(p-anisyl)porphyrin (PdTpAP), Pd(II)-tetrasodium meso-tetra(p-sulfonatophenyl)porphyrin (PdTSTpSPP), Pd(II)-meso-tetra(m-hydroxyphenyl)porphyrin (PdTmHPP), and Pd(II)-meso-tetra(m-carboxyphenyl)porphyrin (PdTmCPP). These porphyrin N-pincer Pd(II)-complexes were studied and found to be effective in the base-free self-coupling reactions of potassium aryltrifluoroborates (PATFBs) in water at ambient conditions. The catalysts and the products (symmetrical biaryls) were characterized using their spectral data. The high yields of the biaryls, the bio-mimicking conditions, good substrate feasibility, evading the use of base, easy preparation and handling of catalysts, and the application of aqueous media, all make this protocol very attractive from a sustainability and cost-effective standpoint.
Pd-catalyzed oxidative homocoupling of arylboronic acids in WEPA: A sustainable access to symmetrical biaryls under added base and ligand-free ambient conditions
Appa, Rama Moorthy,Lakshmidevi, Jangam,Naidu, Bandameeda Ramesh,Venkateswarlu, Katta
, (2021/01/11)
Symmetrical and unsymmetrical biaryls comprises a diverse class of biologically eloquent organic compounds. We herein report, a quick and eco-friendly protocol for the synthesis of biaryls by an oxidative (aerobic) homocoupling of arylboronic acids (ABAs) using Pd(OAc)2 in water extract of pomogranate ash (WEPA) as an efficient agro-waste(bio)-derived aqueous (basic) media. The reactions were executed at ambient aerobic conditions in the absence of external base and ligand to result symmetrical biaryls in excellent yields. The use of renewable media with an effective exploitation of waste, short reaction times, excellent yields of products, easy separation of the products, unnecessating the external base, oxidant, ligand or volatile organic solvents and ambient reaction conditions are the vital insights of the present protocol.