- Nickel-Catalyzed Decarbonylative Cyanation of Acyl Chlorides
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Ni-catalyzed decarbonylative cyanation of acyl chlorides with trimethylsilyl cyanide has been achieved. This transformation is applicable to the synthesis of an array of nitrile compounds bearing a wide range of functional groups under neutral conditions. The step-by-step experimental studies revealed that the reaction sequences of the present catalytic reaction are oxidative addition, transmetalation, decarbonylation, and reductive elimination.
- Wang, Zhenhua,Wang, Xiu,Ura, Yasuyuki,Nishihara, Yasushi
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supporting information
p. 6779 - 6784
(2019/08/26)
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- Decarbonylative Methylation of Aromatic Esters by a Nickel Catalyst
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A Ni-catalyzed decarbonylative methylation of aromatic esters was achieved using methylaluminums as methylating agents. Dimethylaluminum chlorides uniquely worked as the methyl source. Because of the Lewis acidity of aluminum reagents, less reactive alkyl esters could also undergo the present methylation. By controlling the Lewis acidity of aluminum reagents, a chemoselective decarbonylative cross-coupling between alkyl esters and phenyl esters was successful.
- Okita, Toshimasa,Muto, Kei,Yamaguchi, Junichiro
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supporting information
p. 3132 - 3135
(2018/05/28)
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- Discovery of N-aryl-9-oxo-9H-fluorene-1-carboxamides as a new series of apoptosis inducers using a cell- and caspase-based high-throughput screening assay. 2. Structure-activity relationships of the 9-oxo-9H-fluorene ring
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As a continuation of our studies of apoptosis inducing 9-oxo-9H-fluorene-1-carboxamides as potential anticancer agents, we explored modification of the 9-oxo-9H-fluorene ring. SAR studies showed that most changes to the 9-oxo-9H-fluorene ring were not wel
- Kemnitzer, William,Sirisoma, Nilantha,Jiang, Songchun,Kasibhatla, Shailaja,Crogan-Grundy, Candace,Tseng, Ben,Drewe, John,Cai, Sui Xiong
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scheme or table
p. 1288 - 1292
(2010/06/15)
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- SUBSTITUTED N-ARYL-9-OXO-9H-FLUORENE-1-CARBOXAMIDES AND ANALOGS AS ACTIVATOR OF CASPASES AND INDUCERS OF APOPTOSIS
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The present invention is directed to substituted N-aryl-9-oxo-9H-fluorene-1-carboxamides and analogs thereof, represented by the general Formula I: (I) wherein R1-R8, X and Ar are defined herein. The present invention also relates to the discovery that co
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Page/Page column 37
(2010/10/20)
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- Amide compounds
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The present invention is a compound and pharmaceutical composition comprising a compound of formula (I): wherein R1is a 4-(lower) alkyl-imidazol-1-yl or a 4,5-di(lower) alkyl-imidazol-1-yl group, R2is a hydrogen atom or a lower alkyl
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Page column 7
(2010/02/07)
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- NOVEL AMIDE COMPOUNDS
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A compound of the formula (I):R1-A-X-NHCO-Y-R2 ???whereinR1 is heterocyclic group which may have suitable substituents, or phenyl which may have suitable substituents,R2 is condensed phenyl which may have suitable substituents, phenyl which may have suitable substituents, or thienyl which may have suitable substituents,A is a group of the formula:-(CH2)t-(O)m- or in which R3 and R4 are each hydrogen or linked together to form imino,R5 is hydrogen or lower alkyl,t is 0, 1 or 2,p, m and n are each 0 or 1,X is phenylene which may have suitable substituents, or bivalent heterocyclic group containing nitrogen which may have suitable substituents,Y is bond, lower alkylene, or lower alkenylene, and a salt thereof.
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- Design and synthesis of [(2,3-dichlorophenyl)piperazin-1-yl]alkylfluorenylcarboxamides as novel ligands selective for the dopamine D3 receptor subtype
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The dopamine D3 receptor subtype has been recently targeted as a potential neurochemical modulator of the behavioral actions of psychomotor stimulants, such as cocaine. However, definitive behavioral investigations have been hampered by the lack of highly selective D3 agonists and antagonists. In an attempt to design a novel class of D3 ligands with which to study this receptor system, a series of chemically divergent compounds that possessed various structural features that exist within several classes of reputed D3 agents was screened and compared to the recently reported NGB 2904 (58b). On the basis of these results, a novel series of compounds was designed that included functional moieties that were required for high-affinity and selective binding to D3 receptors. All the compounds in this series included an aryl-substituted piperazine ring, a varying alkyl chain linker (C3-C5), and a terminal aryl amide. The compounds were synthesized and evaluated in vitro for binding in CHO cells transfected with human D2, D3, or D4 receptor cDNAs. D3 binding affinities ranged from Ki=1.4 to 1460 nM. The most potent analogue in this series, 51, demonstrated a D3/D2 selectivity of 64 and a D3/D4 selectivity of 1300. Structure-activity relationships for this class of ligands at D3 receptors will provide new leads toward the development of highly selective and potent molecular probes that will prove useful in the elucidation of the role D3 receptors play in the psychomotor stimulant and reinforcing properties of cocaine.
- Robarge,Husbands,Kieltyka,Brodbeck,Thurkauf,Newman
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p. 3175 - 3186
(2007/10/03)
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- Investigation of the Reaction between Amino Acids or Amino Acid Esters and 9-Formylfluorene and Its Equivalents. Possible Utility of the Derived Enamines as Amino Group Protectants
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Treatment of 9-(hydroxymethylene)fluorene/9-formylfluorene (storable as the hemiacetal with methanol, 7) with amino acids and amino acid esters yields the corresponding enamines 8, which may be considered to be hydrocarbon analogues of N-formyl amino acid derivatives.Attempted coupling of the free acids 8 (R'=H) with amino acid esters failed, suggesting insufficient reduction in basicity of the amino group due to the enamine residue.The introduction of electron-withdrawing substituents into the fluorene ring decreases the basicity sufficiently to allow normal peptide coupling reactions, as for example with the 2,7-dichloro analogues derived from 17.Thus phenylalanine derivative 18 treated with leucine methyl ester and DCC gave dipeptide 19.The DC-FM-bar group could be removed by catalytic transfer hydrogenolysis.Mild acid hydrolysis represents a second general deblocking technique for the FM-bar function.It was demonstrated in a model study involving the highly sensitive amino acid α-phenylglycine that the FM-bar protecting group was less prone to cause racemization than the benzyloxycarbonyl function.It was demonstrated that the simple pentapeptide leucine enkephalin 29 could be synthesized using α-DC-FM-bar protection along with tert-butyl-based side chain protecting groups.
- Carpino, Louis A.,Chao, Hann Guang,Tien, Jien-Heh
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p. 4302 - 4313
(2007/10/02)
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- Conformational Preference for the Binding of Biaryl Substrates and Inhibitors to the Active Site of Phenylethanolamine N-Methyltransferase
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We have previously described regions of steric bulk tolerance in the aromatic-ring binding site of phenylethanolamine N-methyltransferase (PNMT, EC 2.1.1.28) for phenylethanolamine substrates and α-methylbenzylamine inhibitors.For bound substrates, this region is located in the vicinity of the para position of the aromatic ring, while for bound α-methylbenzylamine inhibitors, it is located in the region complementary to the meta position.In the present study, we sought to determine the preferred conformation of the biaryl portion of (m-phenylphenyl)- and (p-phenylphenyl)ethanolamine (4 and 5, respectively) as well as for m-phenyl and p-phenyl-α-methylbenzylamine (7 and 8, respectively) for PNMT active site interactions.Planar derivatives of 4,5,7, and 8 were obtained through the synthesis of 2-(1-fluorenyl)-2-hydroxyethylamine (9), 2-(2-fluorenyl)-2-hydroxyethylamine (10), 1-(1-fluorenyl)ethylamine (11), and 1-(2-fluorenyl)ethylamine (12).The four fluorene derivatives were examined for in vitro activity as substrates and inhibitors of the PNMT-catalyzed reaction.As in case of 4, 5, 7, and 8, we have observed a positional preference for the alkylamine side chain with respect to the biphenyl skeleton present in 9-12.Thus, fluorenylethanolamine 10 ("p-biphenyl") displays a Michaelis constant (Km = 26 μM) that is approximately 10 times lower than that for 9 ("m-bipenyl", Km = 297 μM); in the α-methylbenzylamine inhibitors, fluorenyl derivative 11 ("m-biphenyl", Ki = 4.14 μM) is approximately 40 times better than 12 ("p-biphenyl", Ki =185 μM) for in vitro inhibition of PNMT.In each case, conformational restriction of the biaryl system present in 4, 5, 7, and 8, such that the aromatic rings are coplanar, resulted in enhanced affinity for thr PNMT active site.Thus, conformational restriction of ethanolamine 5 (Km = 82 μM) and α-methylbenzylamine 7 (Ki = 89 μM) as in 11 (Ki = 4.14 μM) leads, in each case, to a stronger enzyme-ligand dissociable complex.These results, in conjunction with others from these laboratories, indicate that the PNMT active site beyond the zone that interacts with the central aromatic ring portion of phenylethanolamine substrates and α-methylbenzylamine inhibitors is essentially a flat, hydrophobic pocket.
- Grunewald, Gary L.,Carter, Anne E.,Sall, Daniel J.,Monn, James A.
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