- Exploration of the carmaphycins as payloads in antibody drug conjugate anticancer agents
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Antibody–drug conjugates (ADCs) represent a new dimension of anticancer chemotherapeutics, with warheads to date generally involving either antitubulin or DNA-directed agents to achieve low-to sub-nanomolar potency. However, other potent cytotoxins working by different pharmacological mechanisms are under investigation, such as α,β-epoxyketone based proteasome inhibitors. These proteasome active agents are an emerging class of anticancer drug that possesses ultra-potent cytotoxicity to some cancer cell lines. The carmaphycins are representatives of this latter class that we isolated and characterized from a marine cyanobacterium, and these as well as several synthetic analogues exhibit this level of potency. In the current work, we investigated the use of these highly potent cytotoxic compounds as warheads in the design of novel ADCs. We designed and synthesized a library of carmaphycin B analogues that contain amine handles, enabling their attachment to an antibody linker. The basicity of these incorporated amine handles was shown to strongly affect their cytotoxic properties. Linear amines resulted in the greatest reduction in cytotoxicity whereas less basic aromatic amines retained potent activity as demonstrated by a 4-sulfonylaniline derivative. These investigations resulted in identifying the P2 residue in the carmaphycins as the most suitable site for linker attachment point, and hence, we synthesized a highly potent analogue of carmaphycin B that contained a 4-sulfonylaniline handle as an attachment point for the linker antibody.
- Almaliti, Jehad,Miller, Bailey,Pietraszkiewicz, Halina,Glukhov, Evgenia,Naman, C. Benjamin,Kline, Toni,Hanson, Jeffrey,Li, Xiaofan,Zhou, Sihong,Valeriote, Frederick A.,Gerwick, William H.
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p. 416 - 432
(2018/10/31)
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- Method for synthesizing L L-(+)-selenomethionine (by machine translation)
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The synthetic route disclosed L - (+) - by the invention has, L - (+) - the advantages that the raw materials, are easy to obtain, the reaction conditions are, mild, the reaction conditions are mild, the separation, and purification are easy, L - (+) - and the; method L - (+) - is easy, to separate and purify L - (+) - L - (+) - L - (+) . (by machine translation)
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Paragraph 0041-0045; 0055-0057; 0064-0066; 0073-0075; 0082-0
(2019/12/25)
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- Enantiopure azetidine-2-carboxamides as organocatalysts for direct asymmetric aldol reactions in aqueous and organic media
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A family of enantiopure azetidine-2-caboxamides was asymmetrically synthesized, and was examined as organocatalyst in direct aldol reactions. A well chosen chiral azetidine-2-caboxamide was found to smoothly catalyze the direct aldol reaction of various benzaldehydes with acetone in brine, and β-hydroxy ketones were produced with enantiomeric excess up to 96%. The reaction of benzaldehydes with cyclic ketones also led to the formation of anti-products in diastereomeric ratio up to 99:1 and enantiomeric excess up to 99%.
- Song, Xixi,Liu, Ai-Xiang,Liu, Shan-Shan,Gao, Wen-Chao,Wang, Min-Can,Chang, Junbiao
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p. 1464 - 1470
(2014/02/14)
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- Large-scale, protection-free synthesis of Se-adenosyl-l-selenomethionine analogues and their application as cofactor surrogates of methyltransferases
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S-Adenosyl-l-methionine (SAM) analogues have previously demonstrated their utility as chemical reporters of methyltransferases. Here we describe the facile, large-scale synthesis of Se-alkyl Se-adenosyl-l-selenomethionine (SeAM) analogues and their precursor, Se-adenosyl-l-selenohomocysteine (SeAH). Comparison of SeAM analogues with their equivalent SAM analogues suggests that sulfonium-to-selenonium substitution can enhance their compatibility with certain protein methyltransferases, favoring otherwise less reactive SAM analogues. Ready access to SeAH therefore enables further application of SeAM analogues as chemical reporters of diverse methyltransferases.
- Bothwell, Ian R.,Luo, Minkui
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supporting information
p. 3056 - 3059
(2014/06/23)
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- Discovery of danoprevir (ITMN-191/R7227), a highly selective and potent inhibitor of hepatitis C virus (HCV) NS3/4A protease
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HCV serine protease NS3 represents an attractive drug target because it is not only essential for viral replication but also implicated in the viral evasion of the host immune response pathway through direct cleavage of key proteins in the human innate im
- Jiang, Yutong,Andrews, Steven W.,Condroski, Kevin R.,Buckman, Brad,Serebryany, Vlad,Wenglowsky, Steve,Kennedy, April L.,Madduru, Machender R.,Wang, Bin,Lyon, Michael,Doherty, George A.,Woodard, Benjamin T.,Lemieux, Christine,Do, Mary Geck,Zhang, Hailong,Ballard, Joshua,Vigers, Guy,Brandhuber, Barbra J.,Stengel, Peter,Josey, John A.,Beigelman, Leonid,Blatt, Lawrence,Seiwert, Scott D.
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supporting information
p. 1753 - 1769
(2014/04/03)
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- Synthesis and biological evaluation of novel curcuminoid derivatives
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Curcuminoids have been reported to possess multiple bioactivities, such as antioxidant, anticancer and anti-inflammatory properties. Three novel series of curcuminoid derivatives (11a-h, 15a-h and 19a-d) with enhanced bioactivity have been synthesized. Among the synthesized compounds, 11b exhibited the most significant activity with an MIC of 0.5 μ M /mL against selected medically important Gram-positive cocci (S aureus and S viridans) and Gram-negative bacilli (E. coli and E. cloacae). The derivatives exhibited remarkable results in an antioxidant test with an IC50 2.4- to 9.3-folder smaller than curcuminoids. With respect to antiproliferative activity against Hep-G2, LX-2, SMMC7221 and MDA-MB-231, the derivatives exhibited an effect stronger than curcuminoids with an IC50 ranging from 0.18 to 4.25 μ M.
- Cao, Ya-Kun,Li, Hui-Jing,Song, Zhi-Fang,Li, Yang,Huai, Qi-Yong
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p. 16349 - 16372
(2015/01/08)
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- Total synthesis of the hypermodified RNA bases wybutosine and hydroxywybutosine and their quantification together with other modified RNA bases in plant materials
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We report an efficient synthesis of the hypermodified natural tRNA modifications wybutosine (yW) and hydroxywybutosine (OHyW). We also describe the preparation of isotopically labeled analogues for precise quantification of yW and OHyW in different tissue
- Hienzsch, Antje,Deiml, Christian,Reiter, Veronika,Carell, Thomas
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supporting information
p. 4244 - 4248
(2013/04/23)
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- Synthesis and evaluation of C8-substituted 4.5-spiro lactams as Glycogen Phosphorylase a inhibitors
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An effective synthesis of 4.5-spiro lactams 28/29, has been completed in nine steps with an overall yield of 5.8%. The 4.5-spiro lactams were made from 2-allyl-Cbz-Pro-OMe 21, which was converted into the corresponding alcohol 22 via a hindered borane reaction with (2-methylbutyl)2borane. Subsequent Swern oxidation of 22 gave novel aldehyde 23. Aldehyde 23 was treated under Bucherer-Bergs reaction conditions to give hydantoin 26, which was opened to the corresponding amino acid 30 using di-tert-butyl dicarbonate and DMAP followed by hydrolysis. Treatment of amino acid 30 with acidic methanol gave 4.5-spiro lactams 28/29. Only 4.5-spiro lactam 29 displayed moderate activity against GPa with an IC50 of 241 μM.
- Loughlin, Wendy A.,Schweiker, Stephanie S.,Jenkins, Ian D.,Henderson, Luke C.
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supporting information
p. 1576 - 1582
(2013/03/29)
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- Evaluation of enantiopure N-(ferrocenylmethyl)azetidin-2-yl(diphenyl) methanol for catalytic asymmetric addition of organozinc reagents to aldehydes
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(Chemical Equation Presented) A facile and practical approach to preparation of enantiopure N-(ferrocenylmethyl)azetidin-2-yl(diphenyl)-methanol was developed from cheap and easily available L-(+)-methionine. Synthetic highlights include the three-step, one-pot construction of the chiral azetidine ring and the development of an improved one-step procedure for the synthesis of the key intermediate L-2-amino-4-bromobutanoic acid. Enantiopure N-(ferrocenylmethyl)azetidin-2-yl(diphenyl)methanol was evaluated for catalytic asymmetric addition of organozinc reagents to aldehydes. The asymmetric ethylation, methylation, arylation, and alkynylation of aldehydes achieved enantioselectivity of up to 98.4%, 94.1%, 99.0%, and 84,6% ee, respectively, in the presence of a catalytic amount of chiral N-(ferrocenylmethyl)azetidin-2- yl(diphenyl)methanol. Our results demonstrated further that the four-membered heterocycle-based backbone was a good potential chiral unit for the catalytic asymmetric induction reaction, and the hindrance of the bulky ferrocenyl group, compared to a phenyl group, played an important role in the enantioselectivities. A possible transition for the catalytic asymmetric addition has been proposed on the basis of the crystal structure of the chiral ligand 3b including two HOAc molecules and previous studies.
- Wang, Min-Can,Zhang, Qing-Jian,Zhao, Wen-Xian,Wang, Xiao-Dan,Ding, Xue,Jing, Tao-Tao,Song, Mao-Ping
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p. 168 - 176
(2008/09/17)
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- Nα-Fmoc-protected ω-azido- and ω-alkynyl-L- amino acids as building blocks for the synthesis of "clickable" peptides
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The growing interest in the 1,4-disubstituted-1,2,3-triazolyl moiety as an amide bond surrogate and its formation through very mild, chemoselective, and bioorthogonal CuI-catalyzed Huisgen 1,3-dipolar [3+2] cycloaddition of an alkynyl to an azi
- Isaad, Alexandra Le Chevalier,Barbetti, Francesca,Rovero, Paolo,D'Ursi, Anna Maria,Chelli, Mario,Chorev, Michael,Papini, Anna Maria
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body text
p. 5308 - 5314
(2009/06/18)
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- NOVEL MACROCYCLIC INHIBITORS OF HEPATITIS C VIRUS REPLICATION
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The embodiments provide compounds of the general Formula I, as well as compositions, including pharmaceutical compositions, comprising a subject compound. The embodiments further provide treatment methods, including methods of treating a hepatitis C virus infection and methods of treating liver fibrosis, the methods generally involving administering to an individual in need thereof an effective amount of a subject compound or composition.
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Page/Page column 158-160
(2009/01/20)
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- Syntheses of the P-methylase substrates of the bialaphos biosynthetic pathway
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(Chemical Equation Presented) Genetic studies suggest that either N-acetyldemethyl phosphinothricin (1, N-AcDMPT) or N-acetyldemethyl phosphinothricin tripeptide (2, N-AcDMPTT) is the substrate for the P-methylation reaction in the biosynthesis of phosphinothricin tripeptide (PTT), which is widely used as an herbicide. To study the mechanism for this unique P-methylation reaction catalyzed by the BcpD protein and the functions of the unusual nonribosomal peptide synthetases involved in PTT biosynthesis, this work reports the chemical syntheses of 1 and 2.
- Xiao, Youli,Lee, Kent,Liu, Pinghua
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supporting information; experimental part
p. 5521 - 5524
(2009/06/28)
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- A stereoselective synthesis of phosphinic acid phosphapeptides corresponding to glutamyl-γ-glutamate and incorporation into potent inhibitors of folylpoly-γ-glutamyl synthetase
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Radical addition of H3PO2 to N-/C-protected vinyl glycine led to the corresponding H-phosphinic acid in excellent yield. The non-nucleophilic H-phosphinic acid was converted to a nucleophilic P III species, RP(OTMS)2, which was used in two approaches to the target phosphinic acid containing pseudopeptide. New methodology was developed that led to excellent yields in the reaction of RP(OTMS)2 with unactivated electrophiles, including an acyclic homoallylic bromide. However, en route to the target pseudopeptide, Arbuzov reaction of RP(OTMS) 2 with a cyclic homoallylic bromide, (R)-3-(bromomethyl)-cyclopent-1- ene, led to a rearranged allylic phosphinic acid rather than the desired homoallylic derivative, a putative glutarate surrogate. Conjugate addition of RP(OTMS)2 to α-methylene glutarate containing a chiral auxiliary resulted in only modest diastereoselectivity. Purification by flash chromatography provided protected derivatives of both diastereomers of the pseudopeptide. Following global deprotection, coupling of (S)-H-Glu-γ- [Ψ(P(O)(OH)(CH2))]-(S)-Glu-OH and (S)-H-Glu-γ-[Ψ(P(O) (OH)(CH2))]-(R)-Glu-OH to (4-amino-4-deoxy-10-methyl)pteroyl azide led to the target compounds for biochemical study as inhibitors of the ATP-dependent ligase, folylpoly-γ-glutamate synthetase.
- Hartley, David M.,Coward, James K.
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p. 6757 - 6774
(2007/10/03)
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- Nitric oxide synthase inhibitor phosphate salt
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A compound of formula (I): namely (2S)-2-amino-4-{[2-(etha-nimidoylamino)ethyl]thio}butanoic acid, compound with prosphoric acid, or a solvate or physiologically functional derivative thereof, is useful as a relatively non-hygroscopic selective inhibitor of inducible nitric oxice synthase.
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- An efficient procedure for the preparation of 4-substituted 5-aminoimidazoles
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The preparation of O-methylimidates from α-aminonitriles and their subsequent co-cyclization with primary amines to afford 4-substituted 5-aminoimidazoles was studied. It was found that the mildly acidic pyridinium p-toluenesulfonate efficiently catalyzed each stage of the reaction sequence: (a) the formation of the O-methylimidates, (b) their co-cyclization with a variety of primary amines, and (c) certain derivatizations of the resultant heterocycles. The developed reaction conditions tolerate a wide variety of α-aminonitriles and primary amine co-reactants. Thus, it is possible to easily prepare a diverse array of substituted heterocyclic compounds in good yield. The requisite α-aminonitriles were synthesized either from amino acids or by phase-transfer alkylation of a glycine anion equivalent. The unstable free 5-aminoimidazoles were normally protected in situ to provide derivatives (methyl imidates or N,N-dimethylamidines) that were amenable to characterization.
- McLaughlin, Mark,Mohareb, Rafat M.,Rapoport, Henry
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- LES ORGANOCUPRATES DANS UNE NOUVELLE SYNTHESE D'AMINOACIDES ENANTIOMERIQUEMENT PURS
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A new general method of synthesis of optically pure α- amino esters was elaborated during studies on the reaction of organocuprates with tosyl and halogeno derivatives of L-serine and L-homoserine.
- Bajgrowicz, J. A.,Hallaoui, A. El,Jacquier, R.,Pigiere, Ch.,Viallefont, Ph.
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p. 1833 - 1845
(2007/10/02)
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