- Minisci-Photoredox-Mediated α-Heteroarylation of N-Protected Secondary Amines: Remarkable Selectivity of Azetidines
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The development of a general, mild, and functional-group-tolerant direct functionalization of N-heteroarenes by C-H functionalization with N-protected amines, including azetidines under Minisci-mediated photoredox conditions, is reported. A broad scope of substituted azetidines, including spirocyclic derivatives, and heterocycles were explored. This reaction enables the production of sp3-rich complex druglike structures in one step from unactivated feedstock amines and heterocycles.
- Bosset, Cyril,Beucher, Hélène,Bretel, Guillaume,Pasquier, Elisabeth,Queguiner, Laurence,Henry, Cyril,Vos, Ann,Edwards, James P.,Meerpoel, Lieven,Berthelot, Didier
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Read Online
- Single Electron Transfer-Induced Selective α-Oxygenation of Glycine Derivatives
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Modification of amino acids is an important strategy in organic and bioorganic chemistry. In contrast to common side-chain functionalization, backbone modification is much less explored. Especially glycine units seem to be attractive and versatile since a wide range of functionality can be potentially introduced. We report here oxidative modification of glycinates that are stable and enable further functionalization. Selective glycinate enolate oxidation by TEMPO or a FeCp2PF6/TEMPO reagent combination provides stable alkoxyamines in good to excellent yields. The methodology is expanded to glycine-containing dipeptides demonstrating selective oxygenation at the glycine unit. The orthogonal reactivity potential of oxygenated glycines for transformation to other amino acid derivatives is explored.
- Císa?ová, Ivana,Jahn, Ullrich,K?nig, Burkhard,Moser, Johannes,Venugopal, Navyasree,Vojtí?ková, Margaréta
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supporting information
(2021/11/03)
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- Design and Synthesis of 2-(1-Alkylaminoalkyl)pyrazolo[1,5-a]pyrimidines as New Respiratory Syncytial Virus Fusion Protein Inhibitors
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Respiratory syncytial virus (RSV) is one of the most common causes of lower respiratory tract infections and a significant pathogen for both adults and children. Although two drugs have been approved for the treatment of RSV infections, the low therapeutic index of these drugs have led pharmaceutical companies to develop safe and effective small-molecule anti-RSV drugs. The pyrazolo[1,5-a]pyrimidine series of compounds containing a piperidine ring at the 2-position of the pyrazolo[1,5-a]pyrimidine scaffold are known as candidate RSV fusion (F) protein inhibitor drugs, such as presatovir and P3. The piperidine ring has been revealed to facilitate the formation of an appropriate dihedral angle between the pyrazolo[1,5-a]pyrimidine scaffold and the plane of the amide bond for exertion of anti-RSV activity. A molecular-dynamic study on newly designed compounds with an acyclic chain instead of the piperidine ring proposed and demonstrated a new series of pyrazolo[1,5-a]pyrimidine derivatives, such as 9c with a 1-methyaminopropyl moiety, showing similar dihedral angle distributions to those in presatovir. Compound 9c exhibited potent anti-RSV activity with an EC50 value of below 1nM, which was similar to that of presatovir. A subsequent optimization study on the benzene ring of 9c led to the potent RSV F protein inhibitor 14f with an EC50 value of 0.15nM. The possibility of improving the biological properties of anti-RSV agents by modification at the 7-position of pyrazolo[1,5-a]pyrimidine is also discussed.
- Abe-Kumasaka, Tomoko,Busujima, Tsuyoshi,Iwakiri, Kanako,Kanuma, Kosuke,Kawaguchi, Takanori,Kurosaka, Jun,Ogata, Yuya,Sugaya, Yutaka,Sugiyama, Hiroyuki,Takahashi, Ryo,Tamura, Yunoshin,Tanigawa, Eiji,Ueda-Yonemoto, Naoko,Yamaguchi-Sasaki, Toru
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p. 345 - 362
(2020/05/14)
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- 4,5-Disubstituted 1-Methylimidazoles via Cyclization of Defined α-Aminoketones: Synthesis of Fungerin and Analogues I
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A protocol for the chemoselective synthesis of the fungal metabolite fungerin has been developed. First the required N-methyl α-aminoketone was generated starting from sarcosine, propiolic acid, and prenyl bromide. Marckwald thioimidazole cyclization and subsequent sulfur removal delivered the target fungerin as well as an analogue, respectively, displaying defined substitution patterns.
- Przybyla, Daniel,Nubbemeyer, Udo
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supporting information
p. 770 - 774
(2017/02/15)
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- AZA-PYRIDONE COMPOUNDS AND USES THEREOF
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Disclosed herein are aza-pyridone compounds, pharmaceutical compositions that include one or more aza-pyridone compounds, and methods of synthesizing the same. Also disclosed herein are methods of ameliorating and/or treating a disease and/or a condition, including an orthomyxovirus infection, with an aza-pyridone compounds. Examples of an orthomyxovirus viral infection include an influenza infection.
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Paragraph 0195
(2015/03/16)
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- Study of intramolecular aminolysis in peptides containing N-alkylamino acids at position 2
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Many peptides and proteins, containing Nα-alkylamino acids (including proline) at the second position, are prone to intramolecular aminolysis (IA) with elimination of N-terminal dipeptide sequence as 2,5-diketopiperazines (DKP). We synthesized a series of short peptides, containing N-alkylamino acids at position 2, and studied their stability in the presence of acetic acid and amines. The presence of side chains in the second and the third amino acid residues and alkylation at Nα of the third amino acid residue slowed down IA. Nα-Alkyl residue in the first amino acid residue impeded IA only in peptides, containing three or more residues. Side chains of the first amino acids did not affect significantly the cleavage rates. Acetic acid promoted IA more strongly than aqueous ammonia, while tertiary amines were less effective. Peptides with methionine-S-oxide residues were more labile than the unoxidized analogs, suggesting intramolecular assistance of the S-oxide group in aminolysis. Surprisingly, intermediate compounds of the formula Boc-Met-MeXaa-Sar-NHR underwent rapid cleavage (endopeptolysis) upon attempted acidolytic deprotection.
- Ryakhovsky, Vladimir V.,Ivanov, Andrey S.
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supporting information; experimental part
p. 7070 - 7076
(2012/08/29)
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- Diastereo- and enantioselective hydrogenation of α-amino-β-keto ester hydrochlorides catalyzed by an iridium complex with MeO-BIPHEP and NaBArF: Catalytic cycle and five-membered chelation mechanism of asymmetric hydrogenation
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The development of Ir-catalyzed asymmetric hydrogenation of α-amino-β-keto ester hydrochlorides is described. This reaction proceeds through a dynamic kinetic resolution to produce anti-β-hydroxy- α-amino acid esters in a high diastereo- and enantioselective manner. Mechanistic studies have revealed that this unique asymmetric hydrogenation proceeds through reduction of the ketone moiety via the five-membered transition state involving the chelation between the oxygen of the ketone and the nitrogen of the amine function. The relationship studies between the hydrogen pressure and the stereoselectivity have disclosed two mechanisms dependent on hydrogen pressure. Under low hydrogen pressure (15 atm), the reaction rate proportionally increased with the hydrogen pressure. However, under the high hydrogen conditions, the reaction rate exponentially accelerated along with the increasing hydrogen pressure, which suggests the participation of two or more of hydrogen atoms. Apply some pressure: The Ir-catalyzed asymmetric hydrogenation of α-amino-β-keto ester hydrochlorides proceeds through a dynamic kinetic resolution to produce anti-β-hydroxy-α-amino acid esters in a high diastereo- and enantioselective manner (see scheme). Mechanistic studies revealed that this unique asymmetric hydrogenation proceeds through reduction of the ketone moiety via the five-membered transition state.
- Maeda, Tsukuru,Makino, Kazuishi,Iwasaki, Masamichi,Hamada, Yasumasa
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supporting information; experimental part
p. 11954 - 11962
(2011/01/12)
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- NON-NUCLEOSIDE REVERSE TRANSCRIPTASE INHIBITORS
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Compounds of formula (I), wherein R1, X1, X2 and A, are as defined herein or pharmaceutically acceptable salts thereof, inhibit HIV-1 reverse transcriptase and afford a method for prevention and treatment of HIV-1 infections and the treatment of AIDS and/or ARC. The present invention also relates to compositions containing compounds of formula (I) useful for the prevention and treatment of HIV-1 infections and the treatment of AIDS and/or ARC.
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Page/Page column 40
(2009/01/20)
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- SUBSTITUTED OXIMES AS NEUROKININ ANTAGONISTS
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Compounds within the genus represented by structural formula (I) or a pharmaceutically acceptable salt thereof, wherein: T is substituted phenyl or substituted pyridyl; R is H, methyl, ethyl, -CH2CN, -CH2C(O)NH2, -(CH2)3SO3H, -CH2C(O)NHCH3, -CH2C(O)NHOH, -CH2C(O)NHOCH3, -CH2C(O)NHCH2CN, -CH2F, -CH2C(O)NHCH2SO3H, (a), (b), (c), (d) or (e); R is methyl or ethyl; and Z is substituted piperidinyl.
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- Synthesis and antimitotic/cytotoxic activity of hemiasterlin analogues
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The antimitotic sponge tripeptide hemiasterlin (1) and a number of structural analogues have been synthesized and evaluated in cell-based assays for both cytotoxic and antimitotic activity in order to explore the SAR for this promising anticancer drug lead. One synthetic analogue, SPA110 (8), showed more potent in vitro cytotoxicty and antimitotic activity than the natural product hemiasterlin (1), and consequently it has been subjected to thorough preclinical evaluation and targeted for clinical evaluation. The details of the synthesis of hemiasterlin (1) and the analogues and a discussion of how their biological activities vary with their structures are presented in this paper.
- Nieman, James A.,Coleman, John E.,Wallace, Debra J.,Piers, Edward,Lim, Lynette Y.,Roberge, Michel,Andersen, Raymond J.
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p. 183 - 199
(2007/10/03)
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- Substituted oximes as neurokinin antagonists
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Compounds within the genus represented by the structural formula I or a pharmaceutically acceptable salt thereof, wherein: T is substituted phenyl or substituted pyridyl; R4 is methyl or ethyl; and Z is substituted piperidinyl.
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- 2-(2,3,5,6-tetrafluoro-4-pyridyl)-1,2,5-thiadiazolidin-3-one 1,1-dioxides and compositions and method of use thereof
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2-(2,3,5,6-Tetrafluoro-4-pyridyl)-1,2,5-thiadiazolidin-3-one 1,1-dioxides, pharmaceutical compositions containing them and methods for the treatment of degenerative diseases utilizing them.
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- Selective thrombin inhibitors
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The present invention relates to a novel selective thrombin inhibitor having the following formula (I), which is also effective by oral administration: in which R1represents acetyl substituted with aryl or aryloxy, or represents sulfonyl substituted with substituted or unsubstituted aryl or N-containing heterocyclic group, Xrepresents a group of formula R2and R3independently of one another represent hydrogen; cycloalkyl substituted or unsubstituted with carboxyl or alkoxycarbonyl; arylalkyloxy; hydroxy; or lower alkyl substi tuted or unsubstituted with carboxyl, alkoxycarbonyl or hydroxy, or R2and R3together with nitrogen atom to which they are attached can form a piperidine group substituted with carboxyl or alkoxycarbonyl, R4represents hydrogen, lower alkyl or lower alkoxy, R5represents alkanesulfonyl; alkoxycarbonyl; alkylcarbonyl; formyl; lower alkyl; aryl substituted or unsubstituted with alkoxy or haloalkyl; or hydroxy-substituted lower alkyl,and R6and R7independently of one another represent hydrogen, lower alkyl or amino, and to a process for preparation thereof and a pharmaceutical composition for thrombin inhibition which comprises the compound of formula (I) as an active ingredient.
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- 2-HETEROCYCLYLOXYMETHYL AND 2-HETEROCYCLYLTHIOMETHYL-1.2.5-THIADIAZOLIDIN-3-ONE 1,1-DIOXIDES AND COMPOSITIONS AND METHOD OF USE THEREOF
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2-Heterocyclyloxymethyl and 2-heterocyclylthiomethyL-1,2,5-thiadiazolidin-3-one 1,1-dioxides, pharmaceutical compositions containing them and methods for the treatment of degenerative diseases utilizing them.
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- 2-SUBSTITUTED 1,2,5,-THIADIAZOLIDIN-3-ONE 1,1-DIOXIDES AND COMPOSITIONS AND METHOD OF USE THEREOF
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2-Substituted 1,2,5-thiadiazolidin-3-one 1,1-dioxides, pharmaceutical compositions containing them and methods for the treatment of degenerative diseases utilizing them.
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- SUBSTITUTED 2-(PHOSPHINYLOXYMETHYL)-1,2,5-THIADIAZOLIDIN-3-ONE 1,1-DIOXIDES AND COMPOSITIONS AND METHOD OF USE THEREOF
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Substituted 2-(phosphinyloxymethyl)-1,2,5-thiadiazolidin-3-one 1,1-dioxides, pharmaceutical compositions containing them and methods for the treatment of degenerative diseases utilizing them.
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- SUBSTITUTED 2-ARYLCARBONYLOXYMETHYL-1,2,5-THIADIAZOLIDIN-3-ONE 1,1-DIOXIDE DERIVATIVES AND COMPOSITIONS AND METHOD OF USE THEREOF
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Substituted 2-arylcarbonyloxymethyl-1,2,5-thiadiazolidin-3-one 1,1-dioxide derivatives, pharmaceutical compositions containing them and methods for the treatment of degenerative diseases utilizing them.
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