10602-03-6Relevant articles and documents
Discotic material hexakis(4-carboxyphenylethynyl)benzene inhibits Escherichia coli growth via the glycolysis pathway
Wu, Hsiu-Hui,Chen, Ho-Lun,Hsu, Chih Ying,Yeh, Chih-Ling,Hsu, Hsiu-Fu,Cheng, Chien-Chung
, p. 239 - 244 (2021)
Discotic materials and nanoparticles are potential carriers of synthetic chemicals to increase the bioavailability. Several planar discotic compounds were prepared with C–C bond formation by the Sonagoshira reaction. Their toxicity was based on their inhi
Synthesis and characterization of poly(phenylacetylenes) featuring activated ester side groups
Pauly, Anja C.,Theato, Patrick
, p. 211 - 224 (2011)
Four monomers based on 4-ethynylbenzoic acid have been synthesized, one of those featuring an activated ester. With the metathesis catalytic system WCl6/Ph4Sn, these acetylenic monomers could successfully be polymerized yielding conjugated polymers with molecular weights of around 10,000 to 15,000 g/mol and molecular weight distributions Mw/M n ≤ 2.1. Also the copolymerization of phenylacetylene or methyl 4-ethynylbenzoate with pentafluorophenyl 4-ethynylbenzoate as reactive unit was conducted. Polymer analogous reactions of the reactive polymers and copolymers with amines have been investigated and it was found that poly(pentafluorophenyl 4-ethynylbenzoate) featured a significant reactivity, such that reactions proceeded quantitatively even with aromatic amines. Moreover the UV-Vis spectra of the activated ester based polymer before and after conversion with aliphatic amines showed a change, indicating an effect on the conjugated backbone of the polymers. Copyright
Manganese-Catalyzed ortho-C?H Alkenylation of Aromatic N?H Imidates with Alkynes: Versatile Access to Mono-Alkenylated Aromatic Nitriles
Yang, Xiaoxu,Jin, Xiqing,Wang, Congyang
, p. 2436 - 2442 (2016)
So far, the direct C?H alkenylation of aromatic nitriles with alkynes has not been achieved. Herein, we discribe the first manganese-catalyzed C?H alkenylation of aromatic N?H imidates to access mono-alkenylated aromatic nitriles. The reaction is accelerated by the presence of a catalytic amount of sodium pivalate. This protocol is also highlighted by the simple catalytic system, good compatibility of functional groups, and excellent mono-/dialkenylation selectivity as well as E/Z stereoselectivity. (Figure presented.).
Enantioselective Functionalization of Difluorocyclopropenes Catalyzed by Chiral Copper Complexes: Proposal for Chiral gem-Dimethyl and tert-Butyl Analogues
Sekine, Keisuke,Ushiyama, Aina,Endo, Yu,Mikami, Koichi
, p. 7916 - 7924 (2020)
The highly enantioselective copper/chiral phosphine-catalyzed hydro-, bora-, and carbo-metalations of difluorocyclopropenes with PHMS [H-Si], H-BPin, (BPin)2, and (CH3)2Zn [Zn-Me] are shown to regiodivergently afford highly enantioenriched and functionalized difluorocyclopropanes. These examples can be viewed as the first successful syntheses of "chiral"gem-dimethyl and tert-butyl analogues.
Tunable electron acceptors based on cyclopenta[hi]aceanthrylenes
Zhu, Xinju,Yuan, Bingxin,Plunkett, Kyle N.
, p. 7105 - 7107 (2015)
A series of substituted cyclopenta[hi]aceanthrylene derivatives with electron donating (NH2, OCH3), neutral (H), and electron withdrawing (COOH, CF3, CN, NO2) substituents were prepared. A room-temperature Sonogashira cross-coupling reaction between 2,7-dibromocyclopenta[hi]aceanthrylene and an appropriately functionalized phenylene ethynylene precursor was utilized to access the materials that were characterized by Nuclear Magnetic Resonance Spectroscopy (NMR), cyclic voltammetry (CV), and UV-Vis spectroscopy. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) were systematically varied when proceeding from electron donating to electron withdrawing substituents. The optical band gap was significantly altered for the most electron donating species, while little change was observed between different electron withdrawing substituents. This study demonstrates the ability to control the frontier orbital energies of this class of cyclopenta-fused polycyclic aromatic hydrocarbon materials through selective substitution.
Doyle-kirmse reaction using triazoles leading to one-pot multifunctionalization of terminal alkynes
Miura, Tomoya,Tanaka, Takamasa,Yada, Akira,Murakami, Masahiro
, p. 1308 - 1310 (2013)
1-Sulfonyl-1,2,3-triazoles undergo a Doyle-Kirmse reaction upon treatment with allylic sulfides in the presence of a rhodium(II) catalyst to afford α-allyl-α-sulfanylimines. Terminal alkynes are regioselectively multifunctionalized by the introduction of C-N, C-S, and C-C bonds through a one-pot sequence consisting of a [3 + 2] dipolar cycloaddition reaction with azide and subsequent Doyle-Kirmse reaction.
From Propargylic Alcohols to Substituted Thiochromenes: Gem-Disubstituent Effect in Intramolecular Alkyne Iodo/hydroarylation
Velasco, Noelia,Suárez, Anisley,Martínez-Lara, Fernando,Fernández-Rodríguez, Manuel ángel,Sanz, Roberto,Suárez-Pantiga, Samuel
, p. 7078 - 7091 (2021)
This work describes the 6-endo-dig cyclization of S-aryl propargyl sulfides to afford 2H-thiochromenes. The substitution at the propargylic position plays a crucial role in allowing intramolecular silver-catalyzed alkyne hydroarylation and N-iodosuccinimide-promoted iodoarylation. Additionally, a PTSA-catalyzed thiolation reaction of propargylic alcohols was developed to synthesize the required tertiary S-aryl propargyl ethers. The applicability of merging these two methods is demonstrated by synthesizing the retinoic acid receptor antagonist AGN194310.
Dicarba-closo-dodecaboranes as a pharmacophore. Retinoidal antagonists and potential agonists
Iijima, Toru,Endo, Yasuyuki,Tsuji, Motonori,Kawachi, Emiko,Kagechika, Hiroyuki,Shudo, Koichi
, p. 398 - 404 (1999)
Synthesis and biological evaluation of the first dicarba-closo- dodecaborane (carborane) derivatives of retinoids are described. Their retinoidal activity were examined in terms of the differentiation-inducing ability toward human promyelocytic leukemia HL-60 cells. High retinoidal activity (agonist or antagonist for retinoic acid receptor (RAR)) requires a carboxylic acid moiety and an appropriate hydrophobic group located at a suitable position on the molecule. The 4-carboranyl-substituted compounds (7, 11) showed antagonistic activity but no agonistic activity even in the presence of the potent synergist HX630. On the other hand, the 3-carboranyl- substituted compounds (8, 12) showed potential agonistic activity, but no antagonistic activity. The results indicates that carboranes are applicable as the hydrophobic moiety of biologically active molecules.
Preparation and Reactions of Mono- and Bis-Pivaloyloxyzinc Acetylides
Tüllmann, Carl Phillip,Chen, Yi-Hung,Schuster, Robin J.,Knochel, Paul
, p. 4601 - 4605 (2018)
Mono-pivaloyloxyzinc acetylide and bis-pivaloyloxyzinc acetylide were selectively prepared from ethynylmagnesium bromide in quantitative yields. These zinc reagents readily underwent Negishi cross-couplings with (hetero)aryl iodides or bromides as well as subsequent Sonogashira cross-couplings. 1,3-Dipolar cycloadditions of these zinc acetylides with benzylic azides produced zincated and bis-zincated triazoles which were trapped with several electrophiles. An opposite regioselectivity compared to the Cu-catalyzed click-reactions was observed.
Synthesis and biological evaluation of a novel betulinic acid derivative as an inducer of apoptosis in human colon carcinoma cells (HT-29)
Chakraborty, Biswajit,Dutta, Debasmita,Mukherjee, Sanjukta,Das, Supriya,Maiti, Nakul C.,Das, Padma,Chowdhury, Chinmay
, p. 93 - 105 (2015)
Abstract A novel family of betulinic acid analogues, carrying a triazole unit at C-3 attached through a linker, was synthesized by the application of azide-alkyne "Click reaction". These were screened for their anticancer activity against different cancer cells and normal human PBMC by MTT assay. Compound 2c [(3S)-3-{2-(4-(hydroxymethyl-1H-1,2,3-triazol-1-yl)acetyloxy}-lup-20(29)-en-28-oic acid] was found as the most potent inhibitor of cell line HT-29 with IC50 value 14.9 μM. Its role as an inducer of apoptosis was investigated in this cell line by Annexin-V/PI binding assay and by following its capability for ROS generation, depolarization of mitochondrial transmembrane potential, activation of caspases, PARP cleavage, nuclear degradation and expression of pro- and anti-apoptotic proteins. It exhibited much higher cytotoxicity than the standard drug 5-fluorouracil but showed negligible cytotoxicity towards normal PBMC. Elevated level of ROS generation, activation of caspase 3 and caspase 9, DNA fragmentation, higher expression of Bax and Bad, lower expression of Bcl2 and Bcl-xl, and increased level of Bax/Bcl-xl ratio identified 2c as a promising inducer of apoptosis that follows a mitochondria dependent pathway. Bio-physical studies indicate that compound 2c acts as a minor groove binder to the DNA.
