122-01-0Relevant articles and documents
A General Cp*CoIII-Catalyzed Intramolecular C?H Activation Approach for the Efficient Total Syntheses of Aromathecin, Protoberberine, and Tylophora Alkaloids
Lerchen, Andreas,Knecht, Tobias,Koy, Maximilian,Daniliuc, Constantin G.,Glorius, Frank
, p. 12149 - 12152 (2017)
Herein, we report a Cp*CoIII-catalyzed C?H activation approach as the key step to create highly valuable isoquinolones and pyridones as building blocks that can readily be applied in the total syntheses of a variety of aromathecin, protoberberine, and tylophora alkaloids. This particular C?H activation/annulation reaction was achieved with several terminal as well as internal alkyne coupling partners delivering a broad scope with excellent functional group tolerance. The synthetic applicability of this protocol reported herein was demonstrated in the total syntheses of two Topo-I-Inhibitors and two 8-oxyprotoberberine cores that can be further elaborated into the tetrahydroprotoberberine and the protoberberine alkaloid core. Moreover these building blocks were also transformed to six different tylophora alkaloids in expedient fashion.
Metal-free oxidative self-coupling of aldehydes or alcohols to symmetric carboxylic anhydrides
Gaspa, Silvia,Porcheddu, Andrea,De Luca, Lidia
, p. 2533 - 2536 (2017)
A metal-free synthesis of symmetrical anhydrides has been developed starting from aldehydes, both aliphatic and aromatic or primary benzylic alcohols. The reaction occurs at room temperature and makes use of trichloroisocyanuric acid (TCCA) as an oxidant providing the desired carboxylic anhydrides in satisfactory yields.
Synthesis of N-[4-(alkyl)cyclohexyl]-substituted benzamides with anti-inflammatory and analgesic activities
Pau, Amedeo,Boatto, Gianpiero,Palomba, Michele,Asproni, Battistina,Cerri, Riccardo,Palagiano, Francesco,Filippelli, Walter,Falcone, Giuseppe,Motola, Giulia
, p. 524 - 532 (1999)
Two series of N-[4-(alkyl)cyclohexyl]-substituted benzamides, i.e. a series of N-[4-(tert-butyl)cyclohexyl]-substituted benzamides and a series of N-[4-(ethyl)cyclohexyl]-substituted benzamides, were synthesised and evaluated for their anti-inflammatory and analgesic potencies, and gastrointestinal irritation liability. Copyright (C) 1999 Elsevier Science S.A.
4,5-Diaryl 3(2H)Furanones: Anti-inflammatory activity and influence on cancer growth
Semenok, Dmitrii,Medvedev, Jury,Giassafaki, Lefki-P.,Lavdas, Iason,Vizirianakis, Ioannis S.,Eleftheriou, Phaedra,Gavalas, Antonis,Petrou, Anthi,Geronikaki, Athina
, (2019)
Apart from their anti-inflammatory action, COX inhibitors have gathered the interest of many scientists due to their potential use for the treatment and prevention of cancer. It has been shown that cyclooxygenase inhibitors restrict cancer cell growth and are able to interact with known antitumor drugs, enhancing their in vitro and in vivo cytotoxicity. The permutation of hydrophilic and hydrophobic aryl groups in COX inhibitors leads to cardinal changes in the biological activity of the compounds. In the present study, thirteen heterocyclic coxib-like 4,5-diarylfuran-3(2H)-ones and their annelated derivatives-phenanthro[9,10-b]furan-3-ones-were synthesized and studied for anti-inflammatory and COX-1/2 inhibitory action and for their cytotoxic activity on the breast cancer (MCF-7) and squamous cell carcinoma (HSC-3) cell lines. The F-derivative of the -SOMe substituted furan-3(2H)-ones exhibited the best activity (COX-1 IC50 = 2.8 μM, anti-inflammatory activity (by carrageenan paw edema model) of 54% (dose 0.01 mmol/kg), and MCF-7 and HSC-3 cytotoxicity with IC50 values of 10 μM and 7.5 μM, respectively). A cytotoxic effect related to the COX-1 inhibitory action was observed and a synergistic effect with the anti-neoplastic drugs gefitinib and 5-fluorouracil was found. A phenanthrene derivative exhibited the best synergistic effect with gefitinib.
Equilibrium and Dynamic Dielectric Properties of Acrylate Polymers with (Phenyl)(4-chlorophenyl)methanone Groups in Their Structure
Nunes, R.C.,Diaz-Calleja, R.,Pinto, M.,Saiz, E.,Riande, E.
, p. 12962 - 12970 (1995)
The curves describing the relaxation behavior of poly(4-(acryloxy)phenyl)(4-chlorophenyl)methanone at several frequencies present in the dielectric loss-temperature plane a β relaxation centered at -76 deg C at 10 Hz, whose activation energy shows a slight tendency to increase as the temperature goes up.The relaxation spectra exhibit an ostensible glass-rubber relaxation or α process centered at 106 deg C at 10 Hz, in which free charge conductivity and blocking electrode phenomena become dominant at frequencies below 10 Hz.An electric model is used to separate the dipolar response from conductivity contributions in the glass-rubber relaxation, and the dipole time correlation function for this process is obtained at several temperatures.The intramolecular correlation coefficient gintra, determined from dielectric measurements in solution, is somewhat larger than the coefficient g involving both intra- and intermolecular interactions, obtained from dielectric measurements in the bulk.A rotational state scheme is developed which gives a good account of the intramolecular dipolar correlation coefficient.Finally whereas the relaxation mechanisms involved in the glass-rubber relaxation seem to be governed by the volume, the conductive processes exhibit Arrhenius behavior.
Remarkably Efficient Iridium Catalysts for Directed C(sp2)-H and C(sp3)-H Borylation of Diverse Classes of Substrates
Chattopadhyay, Buddhadeb,Hassan, Mirja Md Mahamudul,Hoque, Md Emdadul
supporting information, p. 5022 - 5037 (2021/05/04)
Here we describe the discovery of a new class of C-H borylation catalysts and their use for regioselective C-H borylation of aromatic, heteroaromatic, and aliphatic systems. The new catalysts have Ir-C(thienyl) or Ir-C(furyl) anionic ligands instead of the diamine-type neutral chelating ligands used in the standard C-H borylation conditions. It is reported that the employment of these newly discovered catalysts show excellent reactivity and ortho-selectivity for diverse classes of aromatic substrates with high isolated yields. Moreover, the catalysts proved to be efficient for a wide number of aliphatic substrates for selective C(sp3)-H bond borylations. Heterocyclic molecules are selectively borylated using the inherently elevated reactivity of the C-H bonds. A number of late-stage C-H functionalization have been described using the same catalysts. Furthermore, we show that one of the catalysts could be used even in open air for the C(sp2)-H and C(sp3)-H borylations enabling the method more general. Preliminary mechanistic studies suggest that the active catalytic intermediate is the Ir(bis)boryl complex, and the attached ligand acts as bidentate ligand. Collectively, this study underlines the discovery of new class of C-H borylation catalysts that should find wide application in the context of C-H functionalization chemistry.
Immobilization of (l)-valine and (l)-valinol on SBA-15 nanoporous silica and their application as chiral heterogeneous ligands in the Cu-catalyzed asymmetric allylic oxidation of alkenes
Samadi, Saadi,Ashouri, Akram,Rashid, Hersh I,Majidian, Shiva,Mahramasrar, Mahsa
supporting information, p. 17630 - 17641 (2021/10/04)
SBA-15 nanoporous silica was synthesized by hydrothermal method using P123 surfactant and tetraethoxyortosilicate in acidic condition and then functionalized by 3-chloropropyltrimethoxysilane. Next, by immobilization of chiral amino acid (S)-2-amino-3-methyl butanoic acid (l-valine) and chiral amino alcohol (S)-2-amino-3-methylbutane-1-ol (l-valinol), preparedviathe reduction ofl-valine by NaBH4/I2in THF, on functionalized-SBA-15, chiral heterogeneous ligands AL*-i-Pr-SBA-15 and AA*-i-Pr-SBA-15 were prepared and characterized by FT-IR, XRD, TGA, EDX, SEM, BET-BJH techniques. The asymmetric allylic oxidation of alkenes was done using copper-complexes of these ligands and the as-synthesized peresters. The reactions were optimized by varying various parameters such as temperature, solvent, amount of chiral heterogeneous ligand, as well as the type and amount of copper salt. Under optimized conditions, 6 mg of AL*-i-Pr-SBA-15 and 3.2 mol% of Cu(CH3CN)4PF6in acetonitrile at 50 °C, the chiral allylic ester was obtained with 80% yield and 39% enantiomeric excess in 24 h. The recyclability of the chiral heterogeneous catalysts was also evaluated without significant reduction in the reaction results up to three runs.
Photochemical Activation of Aromatic Aldehydes: Synthesis of Amides, Hydroxamic Acids and Esters
Nikitas, Nikolaos F.,Apostolopoulou, Mary K.,Skolia, Elpida,Tsoukaki, Anna,Kokotos, Christoforos G.
supporting information, p. 7915 - 7922 (2021/05/03)
A cheap, facile and metal-free photochemical protocol for the activation of aromatic aldehydes has been developed. Utilizing thioxanthen-9-one as the photocatalyst and cheap household lamps as the light source, a variety of aromatic aldehydes have been activated and subsequently converted in a one-pot reaction into amides, hydroxamic acids and esters in good to high yields. The applicability of this method was highlighted in the synthesis of Moclobemide, a drug against depression and social anxiety. Extended and detailed mechanistic studies have been conducted, in order to determine a plausible mechanism for the reaction.
One-step Conversion of Amides and Esters to Acid Chlorides with PCl3
Li, Fangshao,Wu, Xiaofang,Guo, Fengzhe,Tang, Zi-Long,Xiao, Jing
supporting information, p. 4314 - 4317 (2021/07/16)
A general and efficient iodine-promoted chlorination of amides and esters with phosphorus trichloride is described. For the first time. Various inactivated amides including secondary and tertiary amides were directly converted to the corresponding acid chlorides in one-step. The substrate scope of methyl esters including aromatic and aliphatic esters was also explored under this system. This method is simple, scalable and wide in scope, which provides an approach to preparation of these acid chlorides.
PCl3-mediated transesterification and aminolysis of tert-butyl esters via acid chloride formation
Wu, Xiaofang,Zhou, Lei,Li, Fangshao,Xiao, Jing
, p. 491 - 497 (2021/01/20)
A PCl3-mediated conversion of tert-butyl esters into esters and amides in one-pot under air is developed. This novel protocol is highlighted by the synthesis of skeletons of bioactive molecules and gram-scale reactions. Mechanistic studies revealed that this transformation involves the formation of an acid chloride in situ, which is followed by reactions with alcohols or amines to afford the desired products.
