5533-04-0Relevant articles and documents
Cationic Alkynyl Heck Reaction toward Substituted Allenes Using BobCat: A New Hybrid Pd(0)-Catalyst Incorporating a Water-Soluble dba Ligand
Neff, Robynne K.,Frantz, Doug E.
, p. 17428 - 17432 (2018)
The cationic alkynyl Heck reaction between aryl triflates and alkynes to give substituted allenes is described. Key to the success of this method was the discovery and development of a new hybrid Pd(0)-catalyst, BobCat, that incorporates a water-soluble dba-ligand and biaryl phosphine ligand to provide substituted allenes in good yields under mild reaction conditions.
Semi-rigid (Aminomethyl) piperidine-based pentadentate ligands for Mn(II) complexation
Baranyai, Zsolt,Callegari, Edoardo,Cossi, Maurizio,Fraccarollo, Alberto,Martinelli, Jonathan,Tei, Lorenzo
, (2021/10/12)
Two pentadentate ligands built on the 2-aminomethylpiperidine structure and bearing two tertiary amino and three oxygen donors (three carboxylates in the case of AMPTA and two carboxylates and one phenolate for AMPDA-HB) were developed for Mn(II) complexation. Equilibrium studies on the ligands and the Mn(II) complexes were carried out using pH potentiometry,1H-NMR spectroscopy and UV-vis spectrophotometry. The Mn complexes that were formed by the two ligands were more stable than the Mn complexes of other pentadentate ligands but with a lower pMn than Mn(EDTA) and Mn(CDTA) (pMn for Mn(AMPTA) = 7.89 and for Mn(AMPDA-HB) = 7.07).1H and17O-NMR relaxometric studies showed that the two Mn-complexes were q = 1 with a relaxivity value of 3.3 mM?1 s?1 for Mn(AMPTA) and 3.4 mM?1 s?1 for Mn(AMPDA-HB) at 20 MHz and 298 K. Finally, the geometries of the two complexes were optimized at the DFT level, finding an octahedral coordination environment around the Mn2+ ion, and MD simulations were performed to monitor the distance between the Mn2+ ion and the oxygen of the coordinated water molecule to estimate its residence time, which was in good agreement with that determined using the17O NMR data.
68Ga-Labelled Tropane Analogues for the Visualization of the Dopaminergic System
H?seli, Sascha,Holy, Marion,Joksch, Markus,Bergner, Carina,Wree, Andreas,Kurth, Jens,Cankaya, Aylin,Piel, Markus,Krause, Bernd J.,Sitte, Harald H.,R?sch, Frank
supporting information, p. 804 - 808 (2020/12/15)
The development of radiometal-labelled pharmaceuticals for neuroimaging could offer great potential due to easier handling during labelling and availability through radionuclide generator systems. Nonetheless, to date, no such tracers are available for positron emission tomography, primarily owing to the challenge of crossing the blood–brain barrier (BBB) and loss of affinity through chelator attachment. We have prepared a variety of 68Ga-labelled phenyltropanes showing that, through a simple hydrocarbon-linker, it is possible to introduce a chelator onto the lead structure while maintaining its high affinity for hDAT (human dopamine transporter) and simultaneously achieving adequate lipophilicity. One of the candidates, [68Ga]Ga-HBED-hexadiyne-tropane, showed an IC50 value of 66 nM, together with a log D7.4 of 0.96. A μPET study in a hemi-parkinsonian rat model showed a fast wash-out of the tracer, and no specific uptake in the brain, thus implying an inability to penetrate the BBB.
COMBINATION TREATMENT OF BACTERIAL INFECTION
-
Paragraph 0147; 0148, (2020/06/08)
The present invention resides in the discovery that combined use of kuraridin (or any one of its analogs) and epicatechin gallate (ECG) can provide heightened level of antimicrobial activity, especially for the suppression of bacteria of the Staphylococcus aureus and Staphylococcal species. Compositions, kits, and methods for the combination use are disclosed.
Metal-free annulative hydrosulfonation of propiolate esters: synthesis of 4-sulfonates of coumarins and butenolides
Fernandes, Rodney A.,Gangani, Ashvin J.,Kunkalkar, Rupesh A.
, p. 3970 - 3984 (2020/03/19)
An efficient metal-free and cost-effective method for the synthesis of coumarin and butenolide 4-sulfonates (46 examples) has been developed. The reaction involves addition of sulfonic acids to ethyl propiolates followed by lactonization, resulting in direct formation of coumarin and butenolide 4-sulfonates. This methodology has been elaborated to Sonogashira and Suzuki coupling including the synthesis of rac-tolterodine.
Facile Synthesis of 2-Fluorobenzofurans: 5-endo-trig Cyclization of β,β-Difluoro-o-hydroxystyrenes
Morioka, Ryutaro,Fujita, Takeshi,Ichikawa, Junji
, (2020/10/22)
Efficient synthetic methods were established for obtaining 2-fluorobenzofurans involving various substituents. Upon being treated with 1,8-diazabicyclo[5.4.0]undec-7-ene under microwave irradiation, the α-unsubstituted β,β-difluoro-o-hydroxystyrenes under
Design, synthesis, and evaluation of a water soluble C5-monoketone type curcumin analogue as a potent amyloid β aggregation inhibitor
Hotsumi, Mayumi,Tajiri, Misato,Nikaido, Yuri,Sato, Taki,Makabe, Koki,Konno, Hiroyuki
supporting information, p. 2157 - 2161 (2019/07/03)
A structure activity relationship study of curcumin analogues for the inhibition of amyloid β aggregation is described. Optimization of the o-phenol and olefin spacer resulted in the identification of the C5-monoketone type curcumin analogue AY1319, which
Sequential Energy Transfer Catalysis: A Cascade Synthesis of Angularly-Fused Dihydrocoumarins
Nevesely, Tomá?,Daniliuc, Constantin G.,Gilmour, Ryan
supporting information, p. 9724 - 9728 (2019/11/29)
An operationally simple one-pot protocol has been developed to enable the conversion of diversely substituted cinnamic acid derivatives into angularly-fused dihydrocoumarins (up to 94%). Inspired by coumarin biosynthesis, this reaction cascade harnesses photochemical E → Z alkene isomerization enabled by energy transfer catalysis using inexpensive thioxanthen-9-one (TX) under irradiation at 402 nm. Subsequent lactonization generates the heterocyclic core prior to a second photosensitization event to induce a [2 + 2] cycloaddition, again mediated by TX. The tetracyclic products are generated efficiently, and proof of the structure was established by X-ray crystallography. Mechanistic investigations, including structural probes and NMR reaction monitoring, support the postulated order of events. The study underscores the synthetic value of inexpensive small-molecule organic photocatalysts in the generation of structural complexity via sequential ?€-bond activation.
5′-Chloro-2,2′-dihydroxychalcone and related flavanoids as treatments for prostate cancer
Saito, Yohei,Mizokami, Atsushi,Tsurimoto, Hiroyuki,Izumi, Kouji,Goto, Masuo,Nakagawa-Goto, Kyoko
supporting information, p. 1143 - 1152 (2018/09/10)
Several flavonoids and their biosynthetic precursor chalcones were designed and synthesized to improve the biological effects of the lead compound 2′-hydroxyflavonone against androgen receptor (AR)-dependent transcriptional stimulation. Newly synthesized chalcones 19 and 26 suppressed AR-dependent transcription as well as DHT-dependent growth stimulation at a low micromolar level. These compounds were also effective against ligand-independent constitutively active mutant AR derived from castration-resistant PCa (CRPC). Compounds 19 and 26 showed broad spectrum antiproliferative activity at 5–10 μM against multiple tumor cell lines including androgen-independent and taxane-resistant prostate cancer as well as a multidrug-resistant subline. Mode of action studies suggested that 19 induced sub-G1 accumulation in PC-3 cells by disrupting the microtubule network without affecting cell cycle progression. Furthermore, the in vivo effectiveness of chalcone 19 was confirmed in a xenograft model antitumor assay. Thus, chalcone 19 has the potential to be a bifunctional lead for treatment of AR-dependent PCa at lower doses as well as AR-independent PCa, including CRPC, at higher doses.
Synthesis and SAR study of new hydroxy and chloro-substituted 2,4-diphenyl 5H-chromeno[4,3-b]pyridines as selective topoisomerase IIα-targeting anticancer agents
Magar, Til Bahadur Thapa,Seo, Seung Hee,Kadayat, Tara Man,Jo, Hyunji,Shrestha, Aarajana,Bist, Ganesh,Katila, Pramila,Kwon, Youngjoo,Lee, Eung-Seok
, p. 1909 - 1919 (2018/03/07)
As part of our effort to develop potential topoisomerase IIα (topo IIα) targeting anticancer agents, we systematically designed a new series of hydroxy and chloro-substituted 2,4-diphenyl 5H-chromeno[4,3-b]pyridines. Total eighteen compounds were synthesi
