7465-65-8Relevant academic research and scientific papers
Self-Assembly of Chiral-at-End Diketopyrrolopyrroles: Symmetry Dependent Solution and Film Optical Activity and Photovoltaic Performance
Hume, Paul A.,Monks, James P.,Pop, Flavia,Davies, E. Stephen,MacKenzie, Roderick C. I.,Amabilino, David B.
, p. 14461 - 14469 (2018)
Chiral thiophene-diketopyrrolopyrrole derivatives have been synthesised to investigate the potential of stereochemistry and symmetry as a means of modulating properties by influencing self-assembly of these purely organic materials. In particular, derivatives of diketopyrrolopyrrole were employed because of their proven interest as dyes, especially for organic solar cells. The natural product myrtenal was used as the source of stereochemistry, introduced through a Kr?hnke reaction of a thiophene-bearing pyridinium salt and diketopyrrolopyrroles were prepared through Suzuki coupling with this chiral moiety at one end only as well as at both ends. Absorption spectroscopy and electrochemistry confirmed the potential suitability of the compounds for photovoltaic devices. The nanostructures formed by the compounds have been probed with circular dichroism spectroscopy in solution and in films. It is shown that a chiral C2 symmetric molecule assembles in solution giving a strong circular dichroic signal while as a film this optical activity is nulled, whereas an asymmetric homologue is most optically active as a thin film. The X-ray crystal structure of the asymmetric compound shows a polar order of the molecules that might explain this observation. The lack of optical activity in solution is very likely a result of the high solubility of the compound. The results reaffirm the sensitivity of circular dichroism spectroscopy to inter-chromophore organisation, whereas absorption spectroscopy in the visible region reveals only slight changes to the bands. The differing order in the compounds also affects their performance in bulk heterojunction photovoltaic devices. Atomic force microscopy of the blended thin films with the fullerene derivative usually employed (PC61BM) showed that smooth and well mixed films were achieved, with the conditions required during spin coating depending greatly on the derivative, because of their differing solubility. The apparently better performance of the symmetrical compound (although with very low efficiency) is probably a result of the alignment of the molecules inferred by the circular dichroism experiments, whereas the asymmetric compound presumably adopts a twisted supramolecular organisation.
Cyclization of Active Methylene Isocyanides with α-Oxodithioesters Induced by Base: An Expedient Synthesis of 4-Methylthio/Ethoxycarbonyl-5-acylthiazoles
Anil, Seegehalli M.,Kiran, Kuppalli R.,Rajeev, Narasimhamurthy,Rangappa, Kanchugarakoppal S.,Sadashiva, Maralinganadoddi P.,Swaroop, Toreshettahally R.
, p. 1444 - 1450 (2020/04/27)
Cyclization of tosylmethyl isocyanide with α-oxodithioesters in the presence of KOH is reported for the synthesis of 4-methylthio-5-acylthiazoles. Similarly, ethyl isocyanoacetate underwent cyclization with α-oxodithioesters to form 4-ethoxycarbonyl-5-acy
Optimization of Catalyst Structure for Asymmetric Propargylation of Aldehydes with Allenyltrichlorosilane
Vaganov, Vladimir Yu.,Fukazawa, Yasuaki,Kondratyev, Nikolay S.,Shipilovskikh, Sergei A.,Wheeler, Steven E.,Rubtsov, Aleksandr E.,Malkov, Andrei V.
, p. 5467 - 5474 (2020/10/19)
The design of catalysts for asymmetric propargylations remains a challenging task, with only a handful of methods providing access to enantioenriched homopropargylic alcohols. In this work, guided by previously reported computational predictions, a set of
Stereoselective Synthesis of Atropisomeric Bipyridine N,N′-Dioxides by Oxidative Coupling
Fukazawa, Yasuaki,Vaganov, Vladimir Yu.,Shipilovskikh, Sergei A.,Rubtsov, Aleksandr E.,Malkov, Andrei V.
supporting information, p. 4798 - 4802 (2019/06/17)
Bipyridine N,N′-dioxide is a structural fragment found in many bioactive compounds. Furthermore, chiral analogues secured their place as powerful Lewis base catalysts. The scope of the existing methods for the synthesis of atropisomeric bipyridine N,N′-di
Acid-Catalyzed Condensation of o-Phenylenediammines and o-Aminophenols with α-Oxodithioesters: A Divergent and Regio? selective Synthesis of 2-Methylthio-3-Aryl/Heteroarylquinoxalines and 2-Acylbenzoxazoles
Anil, Seegehally M,Kiran, Kuppalli R,Rangappa, Kanchugarakoppal S,Sadashiva, Maralinganadoddi P,Shruthi, Jeegundipattana B,Sukrutha, Kodipura P,Swaroop, Toreshettahally R
, p. 4205 - 4214 (2019/11/14)
o-Phenylenediammines and o-Aminophenols were reacted with α-oxodithioesters in a highly regioselective fashion to give 2-methylthio-3-Aryl/heteroarylquinoxalines and 2-Acylbenzoxazoles in 55-94percent and 45-86percent, respectively, in the presence of p-T
Luminescent PtII Complexes of Tridentate Cyclometalating 2,5-Bis(aryl)-pyridine Ligands
Krause, Maren,Kourkoulos, Dimitrios,González-Abradelo, Darío,Meerholz, Klaus,Strassert, Cristian A.,Klein, Axel
supporting information, p. 5215 - 5223 (2017/10/18)
Bis-cyclometalated PtII complexes of dianionic 2,5-bis(aryl)-pyridine ligands (L1–6)2–, carrying various cyclometalating or pending aryl groups, are synthesised in two steps. The reactions of H2L protoligands with K2[PtCl4] in acetic acid give the mono-cyclometalated complexes [Pt(HL)Cl]2. Heating these complexes in hot DMSO (dimethyl sulfoxide) yields the double-cyclometalated DMSO complexes [Pt(L1–6)(DMSO)]. The reaction of [Pt(L4)(DMSO)] with N,N-dimethylimidazolium iodide in the presence of KOtBu as the base gives the carbene complex [Pt(L4)(Me2Imd)]. Detailed photophysical studies reveal the intense orange luminescence of these complexes in CH2Cl2 solution, with quantum yields up to 0.22, and increased quantum yields of up to 1.00 in glassy frozen CH2Cl2/MeOH (1:1) and up to 0.44 in PMMA matrices. Detailed electrochemistry (including spectroelectrochemistry) reveals reversible ligand-based first reductions at –2.1 to –2.3 V, irreversible Pt-centred oxidations at around 0.8 V and electrochemical band gaps of 2.8–3.0 eV. Further reduction waves at very negative potentials interfere with the solvent (THF with traces of water) discharge and can be traced, with UV/Vis spectroelectrochemistry, to Pt-centred reductions for the DMSO complexes and to a second ligand-centred reduction for the Me2Imd complex from. The photo/electrochemical properties can be roughly correlated with the ligand pattern and suggest their use in optoelectronic applications.
Novel 2-aryl-4-(4′-hydroxyphenyl)-5H-indeno[1,2-b]pyridines as potent DNA non-intercalative topoisomerase catalytic inhibitors
Park, Seojeong,Kadayat, Tara Man,Jun, Kyu-Yeon,Thapa Magar, Til Bahadur,Bist, Ganesh,Shrestha, Aarajana,Lee, Eung-Seok,Kwon, Youngjoo
, p. 14 - 28 (2016/09/23)
On the basis of previous reports on the importance of thienyl, furyl or phenol group substitution on 5H-indeno[1,2-b]pyridine skeleton, a new series of rigid 2-aryl-4-(4′-hydroxyphenyl)-5H-indeno[1,2-b]pyridine derivatives were systematically designed and
Synthesis and biological evaluation of 2-phenol-4-chlorophenyl-6-aryl pyridines as topoisomerase II inhibitors and cytotoxic agents
Thapa, Pritam,Kadayat, Tara Man,Park, Seojeong,Shin, Somin,Thapa Magar, Til Bahadur,Bist, Ganesh,Shrestha, Aarajana,Na, Younghwa,Kwon, Youngjoo,Lee, Eung-Seok
, p. 145 - 159 (2016/05/24)
A new series of 2-phenol-4-chlorophenyl-6-aryl pyridines were designed, synthesized, and evaluated for topoisomerase (topo) I and II inhibitory activities as well as cytotoxic activity against four different human cancer cell lines such as HCT15, T47D, DU
Synthesis of novel C3-linked β-carboline-pyridine derivatives employing khronke reaction: DNA-binding ability and molecular modeling studies
Shankaraiah, Nagula,Sharma, Pankaj,Pedapati, Srinivas,Nekkanti, Shalini,Srinivasulu, Vunnam,Kumar, Niggula Praveen,Kamal, Ahmed
, p. 335 - 342 (2016/04/04)
A series of novel C3-linked β-carboline pyridine (BCP) derivatives have been synthesized via modified Khronke reaction and studied for their DNA-binding affinities. Among all the derivatives, compound 12f has shown significant enhancement in the DNA-binding affinity (ΔTm:6.3 oC and 6.5 oC at 0 h and 18 h incubation) in comparison to the standard Doxorubicin (ΔTm:2.4 oC and 2.6 oC at 0 h and 18 h incubation). This result suggested a strong intercalation with DNA double helix. Moreover, molecular modeling studies also showed that the planar β-carboline ring establishes π-π interactions with DNA base pairs and these interactions are further extended due to the presence of pyridine ring. The DNA intercalation has also been investigated for these compounds by molecular docking and the results are in agreement with thermal denaturation data.
Monitoring the DNA by ruthenium complexes of heterocyclic N,S-donor ligands and evaluation of biological activities
Karia, Parag S.,Vekariya, Pankajkumar A.,Patidar, Anshul P.,Patel, Ravi R.,Patel, Mohan N.
, p. 1903 - 1914 (2016/10/21)
Neutral N,S-donor bidentate ligands have been synthesized and characterized by NMR and IR spectroscopic techniques. The ligands have been used to synthesized ruthenium(II) complexes ([Ru(L1–L6)PPh3)2Cl2/su
