1647-26-3Relevant articles and documents
Catalytic Access to Functionalized Allylic gem-Difluorides via Fluorinative Meyer–Schuster-Like Rearrangement
An, Rui,Li, Huimin,Liao, Lihao,Wu, Jin-Ji,Xu, Yang,Zhao, Xiaodan
supporting information, p. 11010 - 11019 (2020/05/18)
An unprecedented approach for efficient synthesis of functionalized allylic gem-difluorides via catalytic fluorinative Meyer–Schuster-like rearrangement is disclosed. This transformation proceeded with readily accessible propargylic fluorides, and low-cost B–F reagents and electrophilic reagents by sulfide catalysis. A series of iodinated, brominated, and trifluoromethylthiolated allylic gem-difluorides that were difficult to access by other methods were facilely produced with a wide range of functional groups. Importantly, the obtained iodinated products could be incorporated into different drugs and natural products, and could be expediently converted into many other valuable gem-difluoroalkyl molecules as well. Mechanistic studies revealed that this reaction went through a regioselective fluorination of alkynes followed by a formal 1,3-fluorine migration under the assistance of the B–F reagents to give the desired products.
Structure-activity relationship studies of (E)-3,4-dihydroxystyryl alkyl sulfones as novel neuroprotective agents based on improved antioxidant, anti-inflammatory activities and BBB permeability
Chen, Ying,Wu, Bolin,Hao, Yameng,Liu, Yunqi,Zhang, Zhili,Tian, Chao,Ning, Xianling,Guo, Ying,Liu, Junyi,Wang, Xiaowei
, p. 420 - 433 (2019/03/29)
(E)-3,4-dihydroxystyryl alkyl sulfones, as new analogues of neurodegenerative agents, were designed and synthesized. The biological results demonstrated that most of the target compounds preserved antioxidant and anti-inflammatory potency in scavenging reactive free radicals, protecting neuronal cells against neurotoxins such as H2O2, 6-hydroxydopamine and inhibiting lipopolysaccharide (LPS)-induced over-production of NO. Among these compounds, 6.22 with cyclopentyl propyl exhibited prominent antioxidant activity at low concentration (2.5 μM) in H2O2 model (cell viability = 94.5%). In addition, 6.22 (IC50 = 1.6 μM) displayed better anti-inflammatory activity than that of lead compound 1 (IC50 = 13.4 μM). In view of the outstanding performance of 6.22, the apoptotic rates of H2O2-damaged PC12 cells were detected by Annexin V-FITC/PI assay. 6.22 showed higher potency in inhibition of apoptosis than 1 at low concentration (2.5 μM), consisting with the antioxidant and anti-inflammatory models. Furthermore, with the predicted CNS (+) blood-brain barrier (BBB) permeability (Pe = 6.84 × 10?6 cm s?1), low cytotoxicity and favorable physiochemical properties based on calculation, compound 6.22 can be further developed as a potential multifunctional neuroprotective agent.
Metallocene compounds, including the catalyst, the catalyst used in the process of olefin polymers, olefin homopolymers and copolymers and
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Paragraph 0156, (2017/11/01)
PROBLEM TO BE SOLVED: To solve shortcomings of metallocene compounds of the present technology standard and to provide metallocenes that increase desirable characteristics such as high melting point, high molar mass homopolymers and high molar mass copolymers, and do so at higher productivities when used as components of supported catalysts under industrially relevant polymerization conditions at temperatures of from 50 to 100°C.SOLUTION: Certain metallocene compounds are provided that, when used as a component in a supported polymerization catalyst under industrially relevant polymerization conditions, afford high molar mass homo polymers or copolymers like polypropylene or propylene/ethylene copolymers without the need for any α-branched substituent in either of the two available 2-positions of the indenyl ligands.
PROCESS FOR THE PREPARATION OF ORGANIC BROMIDES
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Paragraph 00169; 00171, (2017/07/28)
The present invention provides a process for the preparation of organic bromides, by a radical bromodecarboxylation of carboxylic acids with a bromoisocyanurate.
Catalytic Access to Alkyl Bromides, Chlorides and Iodides via Visible Light-Promoted Decarboxylative Halogenation
Candish, Lisa,Standley, Eric A.,Gómez-Suárez, Adrián,Mukherjee, Satobhisha,Glorius, Frank
supporting information, p. 9971 - 9974 (2016/07/19)
Herein is reported the catalytic, visible light-promoted, decarboxylative halogenation (bromination, chlorination, and iodination) of aliphatic carboxylic acids. This operationally-simple reaction tolerates a range of functional groups, proceeds at room temperature, and is redox neutral. By employing an iridium photocatalyst in concert with a halogen atom source, the use of stoichiometric metals such as silver, mercury, thallium, and lead can be circumvented. This reaction grants access to valuable synthetic building blocks from the large pool of cheap, readily available carboxylic acids.
Metallocene compounds, catalysts comprising them, process for producing an olefin polymer by use of the catalysts, and olefin homo- and copolymers
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Page/Page column 43, (2012/11/07)
Certain metallocene compounds are provided that, when used as a component in a supported polymerization catalyst under industrially relevant polymerization conditions, afford high molar mass homo polymers or copolymers like polypropylene or propylene/ethylene copolymers without the need for any α-branched substituent in either of the two available 2-positions of the indenyl ligands. The substituent in the 2-position of one indenyl ligand can be any radical comprising hydrogen, methyl, or any other C2-C40 hydrocarbon which is not branched in the α-position, and the substituent in the 2-position of the other indenyl ligand can be any C4-C40 hydrocarbon radical with the proviso that this hydrocarbon radical is branched in the β-position. This metallocene topology affords high melting point, very high molar mass homo polypropylene and very high molar mass propylene-based copolymers. The activity/productivity levels of catalysts including the metallocenes of the present invention are exceptionally high.
Triazole ligands reveal distinct molecular features that induce histaine H4 receptor affinity and subtly govern H4/H3 subtype selectivity
Wijtmans, Maikel,De Graaf, Chris,De Kloe, Gerdien,Istyastono, Enade P.,Smit, Judith,Lim, Herman,Boonnak, Ratchanok,Nijmeijer, Saskia,Smits, Rogier A.,Jongejan, Aldo,Zuiderveld, Obbe,De Esch, Iwan J. P.,Leurs, Rob
supporting information; experimental part, p. 1693 - 1703 (2011/05/05)
The histamine H3 (H3R) and H4 (H 4R) receptors attract considerable interest from the medicinal chemistry community. Given their relatively high homology yet widely differing therapeutic promises, ligand selectivity for the two receptors is crucial. We interrogated H4R/H3R selectivities using ligands with a [1,2,3]triazole core. Cu(I)-assisted "click chemistry" was used to assemble diverse [1,2,3]triazole compounds (6a-w and 7a-f), many containing a peripheral imidazole group. The imidazole ring posed some problems in the click chemistry putatively due to Cu(II) coordination, but Boc protection of the imidazole and removal of oxygen from the reaction mixture provided effective strategies. Pharmacological studies revealed two monosubstituted imidazoles (6h,p) with 4R affinities and >10-fold H 4R/H3R selectivity. Both compounds possess a cycloalkylmethyl group and appear to target a lipophilic pocket in H 4R with high steric precision. The use of the [1,2,3]triazole scaffold is further demonstrated by the notion that simple changes in spacer length or peripheral groups can reverse the selectivity toward H3R. Computational evidence is provided to account for two key selectivity switches and to pinpoint a lipophilic pocket as an important handle for H4R over H3R selectivity.
METALLOCENE COMPOUNDS, CATALYSTS COMPRISING THEM, PROCESS FOR PRODUCING AN OLEFIN POLYMER BY USE OF THE CATALYSTS, AND OLEFIN HOMO-AND COPOLYMERS
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, (2010/11/03)
Certain metallocene compounds are provided that, when used as a component in a supported polymerization catalyst under industrially relevant polymerization conditions, afford high molar mass homo polymers or copolymers like polypropylene or propylene/ethylene copolymers without the need for any α-branched substituent in either of the two available 2-positions of the indenyl ligands. The substituent in the 2-position of one indenyl ligand can be any radical comprising hydrogen, methyl, or any other C2-C40 hydrocarbon which is not branched in the α-position, and the substituent in the 2-position of the other indenyl ligand can be any C4-C40 hydrocarbon radical with the proviso that this hydrocarbon radical is branched in the β-position. This metallocene topology affords high melting point, very high molar mass homo polypropylene and very high molar mass propylene-based copolymers. The activity/productivity levels of catalysts including the metallocenes of the present invention are exceptionally high.
Inhibitors of protein isoprenyl transferases
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, (2008/06/13)
Compounds having the formula STR1or a pharmaceutically acceptable salt thereof wherein R 1 is (a) hydrogen, (b) loweralkyl, (c) alkenyl, (d) alkoxy, (e) thioalkoxy, (f) halo, (g) haloalkyl, (h) aryl-L 2 --, and (i) heterocyclic-L 2 --; R 2 is selected from STR2(b) --C(O)NH--CH(R 14)--C(O)OR 15, STR3(d) --C(O)NH--CH(R 14)--C(O)NHSO 2 R 16, (e) --C(O)NH--CH(R 14)-tetrazolyl, (f) --C(O)NH-heterocyclic, and (g) --C(O)NH--CH(R 14)--C(O)NR 17 R 18 ; R 3 is heterocyclic, aryl, substituted or unsubstituted cycloalkyl; R 4 is hydrogen, lower alkyl, haloalkyl, halogen, aryl, arylakyl, heterocyclic, or (heterocyclic)alkyl; L 1 is absent or is selected from (a) --L 4 --N(R 5)--L 5 --, (b) --L 4 --O--L 5 --, (c) --L 4 --S(O) n --L 5 -- (d) --L 4 --L 6 --C(W)--N(R 5)--L 5 --, (e) --L 4 --L 6 --S(O)m--N(R 5)--L 5 --, (f) --L 4 --N(R 5)--C(W)--L 7 --L 5 --, (g) --L 4 --N(R 5)--S(O) p --L 7 --L 5 --, (h) optionally substituted alkylene, (i) optionally substituted alkenylene, and (j) optionally substituted alkynylene are inhibitors of protein isoprenyl transferases. Also disclosed are protein isoprenyl transferase inhibiting compositions and a method of inhibiting protein isoprenyl transferases.
Nucleosides and nucleotides. 107. 2-(cycloalkylalkynyl)adenosines: Adenosine A2 receptor agonists with potent antihypertensive effects
Abiru,Miyashita,Watanabe,Yamaguchi,Machida,Matsuda
, p. 2253 - 2260 (2007/10/02)
Adenosine receptor-binding profiles in rat brain tissues and antihypertensive effects in spontaneously hypertensive rats (SHR) of a series of 2-(cycloalkylalkynyl)adenosine (2-CAAs) and their congeners are described. The structure-activity relationship of this series of compounds is discussed, focusing on the length of the alkynyl side chain and bulkiness of the terminal cycloalkyl substituents in terms of binding activity and cardiovascular effects. All the 2-CAAs had a preferential affinity for A2 receptors. Of these derivatives, 2-(3-cyclopentyl-1-propyn-1-yl)adenosine (10b) exhibited the most selective affinity for A2 receptors (K(i) ratio: A1/A2 = 70) on the basis of receptor binding. In the C-2 binding region of adenosine, compounds often have potent and/or selective A2 activity from introduction of an acetylenic group at the C-2 position followed by one methylene residue further followed by a hydrophobic substituent such as a cycloalkyl ring at the terminal position of the alkynyl side chain. Intravenous injection of 10b up to 100 μg/kg had a potent hypotensive effect without a marked decrease in heart rate in anesthetized SHR. Compounds 10j-s, with a hydroxyl group in the C-3 position of the alkynyl side chain, had a potent affinity for both A1 and A2 receptors, but they were not highly selective for A2 receptors. These compounds caused a marked bradycardia upon intravenous administration in anesthetized SHR. Oral administration of 10b (0.1-1 mg/kg) had a potent and long-lasting antihypertensive effect in conscious SHR.
