30461-77-9Relevant academic research and scientific papers
Pd-Catalyzed desulfitative arylation of olefins by: N -methoxysulfonamide
Ojha, Subhadra,Panda, Niranjan
supporting information, p. 1292 - 1298 (2022/02/19)
A novel Pd-catalyzed protocol for the desulfitative Heck-type reaction of N-methoxy aryl sulfonamides with alkenes was reported. The cross-coupling reaction was performed successfully with a variety of olefins to obtain aryl alkenes. Different substituents on the aromatic ring of N-methoxysulfonamides were also found to be compatible with the reaction conditions. Expectedly, the reaction proceeds through CuCl2-promoted generation of the nitrogen radical and subsequent desulfonylation under thermal conditions to afford the aryl radical for the Pd-catalyzed coupling reaction. N-Methoxysulfonamide was further exploited for the synthesis of symmetrical biaryls in the presence of CuCl2. This journal is
Enantioselective Total Syntheses of Pallambins A–D
Zhang, Xiwu,Cai, Xinxian,Huang, Bin,Guo, Lei,Gao, Zhongrun,Jia, Yanxing
, p. 13380 - 13384 (2019/08/16)
The first enantioselective total syntheses of (?)-pallambins A–D have been achieved in 15 or 16 steps from a known chiral cyclohexenone. Salient features of the syntheses include a palladium-catalyzed oxidative cyclization to assemble the [3.2.1]bicyclic moiety, an Eschenmoser–Claisen rearrangement/lactone formation sequence to construct the C ring, an intramolecular Wittig reaction to form the D ring, and individual transformations of pallambins C and D to generate pallambins A and B. The described synthesis avoids protecting-group manipulations through the design of highly chemo- and stereoselective transformations. During the course of this work, a palladium-catalyzed method for the dehydrobromination of α-bromoketones was developed, and the scope of this transformation was also investigated.
In-vitro and in-vivo antimalarial activity of caffeic acid and some of its derivatives
Alson, Sylvain G.,Jansen, Olivia,Cieckiewicz, Ewa,Rakotoarimanana, Hajatiana,Rafatro, Herintsoa,Degotte, Gilles,Francotte, Pierre,Frederich, Michel
, p. 1349 - 1356 (2018/07/31)
Objectives: To explore the in-vitro and in-vivo antimalarial potential of caffeic acid and derivatives. Methods: Two common phenolic acids (caffeic acid and chlorogenic acid) were evaluated for in-vitro and in-vivo antiplasmodial activity in comparison with some semi-synthetic derivatives that were synthesized. An in-vitro assay based on plasmodial lactate dehydrogenase activity, and the classical in-vivo 5-day suppressive test from Peters on an artemisinin-resistant Plasmodium berghei strain was used. Parasitic stage sensitivity to ethyl caffeate was determined in this work. Key findings: Phenolic acid esters derivatives showed better antiplasmodial activity than corresponding phenolic acids. The derivative with the highest in-vitro activity being caffeic acid ethyl ester, exhibiting an IC50?=?21.9?±?9.4?μm. Ethyl caffeate and methyl caffeate were then evaluated for antimalarial activity in?vivo and ethyl caffeate showed a growth inhibition of 55% at 100?mg/kg. Finally, it seems that ethyl caffeate blocks the growth of young parasitic forms. Conclusions: Our study provides evidence for an antimalarial potential of caffeic acid derivatives which are common in several medicinal plants traditionally used against malaria. It also demonstrates the possibility to use such derivatives in the treatment of malaria.
A Mixed-Ligand Chiral Rhodium(II) Catalyst Enables the Enantioselective Total Synthesis of Piperarborenine B
Panish, Robert A.,Chintala, Srinivasa R.,Fox, Joseph M.
supporting information, p. 4983 - 4987 (2016/04/26)
A novel, mixed-ligand chiral rhodium(II) catalyst, Rh2(S-NTTL)3(dCPA), has enabled the first enantioselective total synthesis of the natural product piperarborenine B. A crystal structure of Rh2(S-NTTL)3(dCPA) r
The palladium slow-release pre-catalysts and nanoparticles in the "phosphine-free" Mizoroki-Heck and Suzuki-Miyaura reactions
Sigeev, Alexander S.,Peregudov, Alexander S.,Cheprakov, Andrei V.,Beletskaya, Irina P.
supporting information, p. 417 - 429 (2015/02/19)
The Mizoroki-Heck reaction of electronrich aryl iodides was studied using a phosphine-free catalytic system with a broad range of pre-catalysts of varied stability and structure based on organoselenium chelators. The application of the "mercury test" by observing the response of the catalytic systems studied not only to the addition, but also to the withdrawal of Hg allowed us to establish a critical role of nanoparticles in the operation of the phos-phine-free catalytic systems. A three-stage mechanistic scheme involving a slow stage served by mononuclear Pd species, and the main fast stage served by Pd nanoparticles, and terminated by the nanoparticle decay is proposed as a general mechanistic paradigm for the phosphine-free Mizoroki-Heck and the related Suzuki-Miyaura reactions.
Synthesis and antimicrobial activities of 4-aryl-3,4-dihydrocoumarins and 4-arylcoumarins
Sun, Jie,Ding, Wei-Xian,Hong, Xiao-Ping,Zhang, Ke-Yun,Zou, Yong
experimental part, p. 16 - 22 (2012/07/28)
A new series of 4-aryl-3,4-dihydrocoumarins and 4-arylcoumarins were synthesized by the reaction of substituted cinnamic acids and 3-arylpropiolic acid with the corresponding phenols. These compounds were evaluated for antibacterial activity in vitro. The
Tandem allylic oxidation-condensation/esterification catalyzed by silica gel: An expeditious approach towards antimalarial diaryldienones and enones from natural methoxylated phenylpropenes
Sharma, Abhishek,Sharma, Naina,Shard, Amit,Kumar, Rakesh,Mohanakrishnan, Dinesh,Saima,Sinha, Arun K.,Sahal, Dinkar
, p. 5211 - 5219 (2011/08/07)
A new one-pot strategy has been developed, wherein abundantly available methoxylated phenylpropenes are directly transformed into corresponding dienones (1,5-diarylpenta-2,4-dien-1-ones) and enones (chalcones and cinnamic esters) via allylic oxidation-condensation or allylic oxidation-esterification sequences. Preliminary antimalarial activity studies of the above synthesized diaryldienones and enones against Plasmodium falciparum (Pf3D7) have shown them to be promising lead candidates for developing newer and economical antimalarial agents. In particular, two enones (12b and 13b) were found to possess comparatively better activity (IC50 = 4.0 and 3.4 μM, respectively) than licochalcone (IC50 = 4.1 μM), a well known natural antimalarial compound. The Royal Society of Chemistry 2011.
OXADIAZOLE COMPOUNDS, THEIR PREPARATION AND USE
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Page/Page column 74, (2011/09/30)
The present invention relates to oxadiazole compounds in all their stereoisomeric and tautomeric forms and mixtures thereof in all ratios; and their pharmaceutically acceptable salts, pharmaceutically acceptable solvates, pharmaceutically acceptable prodrugs and pharmaceutically acceptable polymorphs. The invention also relates to processes for the manufacture of the oxadiazole compounds and to pharmaceutical compositions containing them. The said compounds and their pharmaceutical compositions are useful in the treatment of cancer, particularly chronic myeloid leukemia (CML). The present invention further provides a method of treatment of cancer by administering a therapeutically effective amount of said compounds or their pharmaceutical compositions, to a mammal in need thereof.
Bifunctional phenolic-choline conjugates as anti-oxidants and acetylcholinesterase inhibitors
Sebestik, Jaroslav,Marques, Sergio M.,Fale, Pedro L.,Santos, Susana,Arduino, Daniela M.,Cardoso, Sandra M.,Oliveira, Catarina R.,Serralheiro, M. Luisa M.,Santos, M. Amelia
experimental part, p. 485 - 497 (2012/05/19)
Because of the complex cascade of molecular events that can occur in the brain of an Alzheimer's disease (AD) patient, the therapy of this neurodegenerative disease seems more likely to be achieved by multifunctional drugs. Herein, a new series of dual-targeting ligands have been developed and in vitro bioevaluated. Their architecture is based on conjugating the acetylcholinesterase inhibition and anti-oxidant properties in one molecular entity. Specifically, a series of naturally occurring phenolic acids with recognized anti-oxidant properties (derivatives of caffeic acid, rosmarinic acid, and trolox) have been conjugated with choline to account for the recognition by acetylcholinesterase (AChE). The synthesized hybrid compounds evidenced AChE inhibitory capacity of micromolar range (rationalized by molecular modeling studies) and good antioxidant properties. Their effects on human neuroblastoma cells, previously treated with beta-amyloid peptides and 1-methyl-4-phenylpyridinium ion neurotoxins (to simulate AD and Parkinson's disease, respectively), also demonstrated a considerable capacity for protection against the cytotoxicity of these stressors.
An efficient route to xanthine based A2A adenosine receptor antagonists and functional derivatives
Labeaume, Paul,Dong, Ma,Sitkovsky, Michail,Jones, Elizabeth V.,Thomas, Rhiannon,Sadler, Sara,Kallmerten, Amy E.,Jones, Graham B.
supporting information; experimental part, p. 4155 - 4157 (2010/10/21)
A one-pot route to 8-substituted xanthines has been developed from 5,6-diaminouracils and carboxaldehydes. Yields are good and the process applicable to a range of substrates including a family of A2A adenosine receptor antagonists. A new route to the KW-6002 family of antagonists is presented including a pro-drug variant, and application to related image contrast agents developed.
