- Identification and Profiling of a Novel Diazaspiro[3.4]octane Chemical Series Active against Multiple Stages of the Human Malaria Parasite Plasmodium falciparum and Optimization Efforts
-
A novel diazaspiro[3.4]octane series was identified from a Plasmodium falciparum whole-cell high-throughput screening campaign. Hits displayed activity against multiple stages of the parasite lifecycle, which together with a novel sp3-rich scaffold provided an attractive starting point for a hit-to-lead medicinal chemistry optimization and biological profiling program. Structure-activity-relationship studies led to the identification of compounds that showed low nanomolar asexual blood-stage activity (50 nM) together with strong gametocyte sterilizing properties that translated to transmission-blocking activity in the standard membrane feeding assay. Mechanistic studies through resistance selection with one of the analogues followed by whole-genome sequencing implicated the P. falciparum cyclic amine resistance locus in the mode of resistance.
- Le Manach, Claire,Dam, Jean,Woodland, John G.,Kaur, Gurminder,Khonde, Lutete P.,Brunschwig, Christel,Njoroge, Mathew,Wicht, Kathryn J.,Horatscheck, André,Paquet, Tanya,Boyle, Grant A.,Gibhard, Liezl,Taylor, Dale,Lawrence, Nina,Yeo, Tomas,Mok, Sachel,Eastman, Richard T.,Dorjsuren, Dorjbal,Talley, Daniel C.,Guo, Hui,Simeonov, Anton,Reader, Janette,Van Der Watt, Mari?tte,Erlank, Erica,Venter, Nelius,Zawada, Jacek W.,Aswat, Ayesha,Nardini, Luisa,Coetzer, Theresa L.,Lauterbach, Sonja B.,Bezuidenhout, Belinda C.,Theron, Anjo,Mancama, Dalu,Koekemoer, Lizette L.,Birkholtz, Lyn-Marie,Wittlin, Sergio,Delves, Michael,Ottilie, Sabine,Winzeler, Elizabeth A.,Smith, Dennis,Fidock, David A.,Street, Leslie J.,Basarab, Gregory S.,Duffy, James,Chibale, Kelly
-
supporting information
p. 2291 - 2309
(2021/03/01)
-
- Thiamine hydrochloride as a recyclable organocatalyst for the efficient and chemoselective N-tert-butyloxycarbonylation of amines
-
Thiamin hydrochloride promoted highly efficient and ecofriendly approach has been described for the chemoselective N-tert-butyloxycarbonylation of amines under solvent-free conditions at ambient temperature. The demonstrated approach has been applicable for the N-Boc protection of variety of aliphatic, aryl, heteroaryl amines. The chemoselective protection of amino group occurs in chiral amines and amino alcohol without racemization in high yield. Thiamin hydrochloride is stable, economical, easy to handle and environmentally friendly.
- Ingale, Ajit P.,Garad, Dnyaneshwar N.,Ukale, Dattatraya,Thorat, Nitin M.,Shinde, Sandeep V.
-
supporting information
p. 3791 - 3804
(2021/11/04)
-
- 4 - Fluorine substituted aryl amine compound and synthesis method thereof
-
The invention discloses a synthesis method of 4 -fluorine substituted aryl amine compound, which comprises the following steps: 1) taking acyl-protected phenylhydroxylamine as a substrate, and generating 4 -fluorine substituted aniline compound under basic conditions by taking sulfonyl fluoride as a fluorine source in a polar solvent. 2) The deprotection is carried out under dilute acid conditions or Pd by catalytic hydrogenation to give the 4 - fluorine-substituted aryl amine compound. 4 - Fluorine substituted aniline compounds which are synthesized by the invention greatly increase the lipophilic property due to the introduction of fluorine atoms, and can be widely applied to preparation of fluorine-containing drugs and pesticide and dye intermediates. , The adopted raw materials are industrial products, are cheap and easily available, and are commercially available. 4 - Fluoroaryl aniline prepared by the method is high in yield, and the product with the purity 90% can be obtained in a yield of more than ≥ 99%. The method is simple to operate and low in cost, is very suitable for industrialization, and can be widely popularized and used.
- -
-
Paragraph 0050-0051
(2021/09/22)
-
- Integrating Hydrogen Production and Transfer Hydrogenation with Selenite Promoted Electrooxidation of α-Nitrotoluenes to E-Nitroethenes
-
Developing an electrochemical carbon-added reaction with accelerated kinetics to replace the low-value and sluggish oxygen evolution reaction (OER) is markedly significant to pure hydrogen production. Regulating the critical steps to precisely design electrode materials to selectively synthesize targeted compounds is highly desirable. Here, inspired by the surfaced adsorbed SeOx2? promoting OER, NiSe is demonstrated to be an efficient anode enabling α-nitrotoluene electrooxidation to E-nitroethene with up to 99 % E selectivity, 89 % Faradaic efficiency, and the reaction rate of 0.25 mmol cm?2 h?1 via inhibiting side reactions for energy-saving hydrogen generation. The high performance can be associated with its in situ formed NiOOH surface layer and absorbed SeOx2? via Se leaching-oxidation during electrooxidation, and the preferential adsorption of two -NO2 groups of intermediate on NiOOH. A self-coupling of α-carbon radicals and subsequent elimination of a nitrite molecule pathway is proposed. Wide substrate scope, scale-up synthesis of E-nitroethene, and paired productions of E-nitroethene and hydrogen or N-protected aminoarenes over a bifunctional NiSe electrode highlight the promising potential. Gold also displays a similar promoting effect for α-nitrotoluene transformation like SeOx2?, rationalizing the strategy of designing materials to suppress side reactions.
- Chong, Xiaodan,Liu, Cuibo,Wang, Changhong,Yang, Rong,Zhang, Bin
-
supporting information
p. 22010 - 22016
(2021/09/02)
-
- Electrophotocatalytic SNAr Reactions of Unactivated Aryl Fluorides at Ambient Temperature and Without Base
-
The electrophotocatalytic SNAr reaction of unactivated aryl fluorides at ambient temperature without strong base is demonstrated.
- Huang, He,Lambert, Tristan H.
-
supporting information
p. 658 - 662
(2019/11/28)
-
- Highly efficient chemoselective N-tert butoxycarbonylation of aliphatic/aromatic/heterocyclic amines using diphenylglycoluril as organocatalyst
-
An efficient approach for the Chemoselective N-tert-butoxycarbonylation of a variety of amines using diphenylglycoluril as organocatalyst has been described. For the first time, a plausible mechanism for the N-tert-butoxycarbonylation has been proposed using density functional theory (DFT) calculations supported by NMR studies. The reusability of the organocatalyst and observation of the desired N-Boc protected amines being formed without the formation of side products like urea, oxazolidinone, isocyanate, and N, N-di-Boc derivatives makes the present protocol desirable.
- Awasthi, Amardeep,Mukherjee, Anagh,Singh, Mandeep,Rathee, Garima,Vanka, Kumar,Chandra, Ramesh
-
-
- ACETAMIDO DERIVATIVES AS DNA POLYMERASE THETA INHIBITORS
-
Disclosed herein are certain acetamido derivatives that are DNA Polymerase Theta (Polθ) inhibitors of Formula (I). Also, disclosed are pharmaceutical compositions comprising such compounds and methods of treating diseases treatable by inhibition of Polθ such as cancer, including homologous recombination (HR) deficient cancers.
- -
-
Paragraph 0264
(2020/08/22)
-
- Harnessing Cascade Suzuki-Cyclization Reactions of Pyrazolo[3,4-b]pyridine for the Synthesis of Tetracyclic Fused Heteroaromatics
-
Numerous procedures have been described for the functionalization of pyrazolo[3,4-b]pyridine, mainly involving nucleophilic substitutions at the C-4 position or esterifications/amidations at the C-5 position. In this paper, we describe a robust, easy to implement protocol for the Suzuki cross-coupling reaction of chloroarene 2, followed by in-situ lactonization to provide chromenopyrazolopyridines. The extension of the scope of the reaction to fused naphthyridinones is also reported. This strategy gave access to 10 original pyrazolopyridine-containing tetracyclic compounds.
- Lavrard, Hubert,Popowycz, Florence
-
supporting information
p. 600 - 608
(2017/02/05)
-
- [TPA][Pro] ionic liquid as efficient reaction medium for N-tert-Boc protection of amines
-
A facile and efficient N-tert-Boc protection of amines is described by the reaction of various primary, secondary, benzylic and aryl amines with di-tert-butyl dicarbonate in the ionic liquid [TPA][Pro] at room temperature. All the N-tert-butylcarbamates are afforded in excellent yields. A catalyst-free method was developed and the ionic liquid [TPA][Pro] can be recovered and reused for several times without loss of its activity.
- Vijaya Durga,Rambabu,Srinivasa Reddy,Hari Babu
-
p. 1313 - 1316
(2017/05/02)
-
- Ligand-Promoted Meta-C-H Arylation of Anilines, Phenols, and Heterocycles
-
Here we report the development of a versatile 3-acetylamino-2-hydroxypyridine class of ligands that promote meta-C-H arylation of anilines, heterocyclic aromatic amines, phenols, and 2-benzyl heterocycles using norbornene as a transient mediator. More than 120 examples are presented, demonstrating this ligand scaffold enables a wide substrate and coupling partner scope. Meta-C-H arylation with heterocyclic aryl iodides as coupling partners is also realized for the first time using this ligand. The utility for this transformation for drug discovery is showcased by allowing the meta-C-H arylation of a lenalidomide derivative. The first steps toward a silver-free protocol for this reaction are also demonstrated.
- Wang, Peng,Farmer, Marcus E.,Huo, Xing,Jain, Pankaj,Shen, Peng-Xiang,Ishoey, Mette,Bradner, James E.,Wisniewski, Steven R.,Eastgate, Martin D.,Yu, Jin-Quan
-
supporting information
p. 9269 - 9276
(2016/08/05)
-
- Highly ortho-Selective Chlorination of Anilines Using a Secondary Ammonium Salt Organocatalyst
-
An organocatalytic, highly facile, efficient, and regioselective ortho-chlorination of anilines is described. A secondary ammonium chloride salt has been employed as the catalyst and the reaction can be conducted at room temperature without protection from air and moisture. In addition, the reaction is readily scalable and the catalyst can be recycled and reused. This catalytic protocol has been applied to the efficient synthesis of a highly potent c-Met kinase inhibitor. Mechanistic studies revealed that unique structural features of the secondary ammonium chloride salt are important for both the catalysis and regioselectivity of the electrophilic ortho-chlorination.
- Xiong, Xiaodong,Yeung, Ying-Yeung
-
supporting information
p. 16101 - 16105
(2016/12/26)
-
- A 2,6-bis(phenylamino)pyridinato titanium catalyst for the highly regioselective hydroaminoalkylation of styrenes and 1,3-butadienes
-
The C-C bond forming catalytic hydroaminoalkylation of terminal alkenes, 1,3-dienes, or styrenes allows a direct and highly atom efficient (100 %) synthesis of amines which can result in the formation of two regioisomers, the linear and the branched product. We present a new titanium catalyst with 2,6-bis(phenylamino)pyridinato ligands for intermolecular hydroaminoalkylation reactions of styrenes and 1-phenyl-1,3-butadienes that delivers the corresponding linear hydroaminoalkylation products with excellent regioselectivities. Linear progress: A new Ti complex with 2,6-bis(phenylamino) pyridinato ligands catalyzes highly regioselective hydroaminoalkylation reactions of styrenes. The process that directly gives access to the corresponding linear hydroaminoalkylation products offers a new and flexible synthetic approach towards pharmaceutically important 3-arylpropylamines. It is also possible to convert (E)-1-phenyl-1,3-butadienes into the corresponding linear products.
- Doerfler, Jaika,Preuss, Till,Schischko, Alexandra,Schmidtmann, Marc,Doye, Sven
-
supporting information
p. 7918 - 7922
(2014/08/05)
-
- INHIBITORS OF THE MITF MOLECULAR PATHWAY
-
Provided herein are compounds of the formula (IV) as well as pharmaceutically acceptable salts thereof, wherein the substituents are as those disclosed in the specification. These compounds, and the pharmaceutical compositions containing them, are useful as MITF inhibitors, MITF pathway inhibitors and for the treatment of cancer.
- -
-
Paragraph 00175
(2015/01/09)
-
- Fluorine Radiolabelling Process
-
The invention relates to a process for producing a process for producing an 18F-labelled compound, the process comprising treating a compound of formula (I) wherein EDG is an electron-donating group selected from —OH, —OR4, —NHR5 and —NR55R5; R1, R2, X1 and X2 are as defined herein; and R3 is selected from H, X3 and X4, wherein X3 is a monodentate cleavable surrogate group, and X4 is a bidentate cleavable surrogate group which is bonded (a) to said X1 or X2 and (b) to the ring carbon atom para to EDG; with [18F]fluoride in the presence of an oxidant, thereby producing, when R3 in the compound of formula (I) is H, an 18F-labelled compound of formula (II), wherein EDG is as defined above and R1, R2, X1 and X2 are as defined herein; or thereby producing, when R3 in the compound of formula (I) is said monodentate cleavable surrogate group X3, a compound of formula (IIa), wherein EDG′ is O, NR5, —NR55R5 or [OR4]+, and wherein R4, R5, R55, R1, R2, X1, X2 and X3 are as defined herein; or thereby producing, when R3 in the compound of formula (I) is said bidentate cleavable surrogate group X4, a compound of formula (IIc) or a compound of formula (IId), wherein EDG′ is O, NR5, —NR55R5 or [OR4]+, and wherein R4, R5, R55, R1, R2, X1, X2 and X4 are as defined herein
- -
-
Paragraph 0490
(2013/07/31)
-
- Solvent free N-Boc protection of amines using amberlystr a 21 solid base resin as a reusable heterogeneous catalyst
-
An efficient, environmentally benign, highly facile and convenient synthetic protocol for the selective t-butyl carboxylation of aliphatic, aromatic and heterocyclic amines using AmberlystR A 21 catalyst; a mild basic solid resin under solvent free conditions is reported. This method explores several advantages such as reusability of the heterogeneous catalyst, cleaner reaction profile, mild and solvent free system, short reaction time, operational simplicity, high conversions , excellent product yields and low cost of the catalyst. Furthermore since the catalyst is mild basic, decomposition of the carbamate formed is not observed if the reaction is continued for prolonged time as in the case of Lewis acid catalyzed N-Boc protection. This makes the present protocol a useful and attractive for N-Boc protection of amines.
- Tekale, Sunil U.,Kauthale, Sushama S.,Pawar, Rajendra P.
-
p. 1619 - 1623
(2013/09/12)
-
- Zinc chloride promoted efficient and facile BOC protection of amines
-
Amines are efficiently protected as their BOC derivatives under mild reaction conditions when reacted with BOC anhydride in presence of ZnCl2. The present method is applicable to a variety of amines including aliphatic, aromatic as well as heteroaromatic amines. This protocol appears to be competitive and in some cases superior to previously reported procedures that work under basic conditions.
- Arifuddin, M.,Lakshmikant, N.,Rajasekar, N.,Shinde, D. B.
-
p. 1168 - 1172,5
(2020/08/31)
-
- FLUORINE RADIOLABELLING PROCESS
-
The invention relates to a process for producing a process for producing an 18F-labelled compound, the process comprising treating a compound of formula (I): wherein EDG is an electron-donating group selected from -OH, -OR4, -NHR5 and -NR55R5; R1, R2, X1 and X2 are as defined herein; and R3 is selected from H, X3 and X4, wherein X3 is a monodentate cleavable surrogate group, and X4 is a bidentate cleavable surrogate group which is bonded (a) to said X or X and (b) to the ring carbon atom para to EDG; with [18F]fluoride in the presence of an oxidant, thereby producing, when R3 in the compound of formula (I) is H, an 18F-labelled compound of formula (II), wherein EDG is as defined above and R1, R2, X1 and X2 are as defined herein; or thereby producing, when R3 in the compound of formula (I) is said monodentate cleavable surrogate group X4, a compound of formula (Ilc), wherein EDG' is O, NR5, -NR55R5 or [OR4]+, and wherein R4, R5, R55, R1, R2, X1, X2 and X3 are as defined herein; or thereby producing, when R3 in the compound of formula (I) is said bidentate cleavable surrogate group X4, a compound of formula (IIc) or a compound of formula (IId), wherein EDG' is O, NR5, -NR55R5 or [OR4]+, and wherein R4, R5, R55, R1, R2, X1, X2 and X4 are as defined herein.
- -
-
Page/Page column 81
(2012/02/01)
-
- Simple and efficient method for n-boc protection of amines using PEG-400 as a reaction medium under mild conditions
-
Simple and efficient method for N-Boc protection of amines using PEG-400 as an ecofriendly reaction medium at room temperature is described. Various aromatic, heteroaromatic, and aliphatic amines were converted to the corresponding N-tert-butyl-carbamates in good to excellent yields in short times.
- Zeng, Hongyao,Li, Yongjia,Shao, Huawu
-
experimental part
p. 25 - 32
(2011/10/19)
-
- Nonsolvent application of ionic liquids: Organo-catalysis by 1-alkyl-3-methylimidazolium cation based room-temperature ionic liquids for chemoselective N-tert-butyloxycarbonylation of amines and the influence of the C-2 hydrogen on catalytic efficiency
-
1-Alkyl-3-methylimidazolium cation based ionic liquids efficiently catalyze N-tert-butyloxycarbonylation of amines with excellent chemoselectivity. The catalytic role of the ionic liquid is envisaged as "electrophilic activation" of di-tert-butyl dicarbonate (Boc2O) through bifurcated hydrogen bond formation with the C-2 hydrogen of the 1-alkyl-3-methylimidazolium cation and has been supported by a downfield shift of the imidazolium C-2 hydrogen of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][NTf2]) from δ 8.39 to 8.66 in the presence of Boc2O in the 1H NMR and a drastic reduction of the catalytic efficiency with 1-butyl-2,3-dimethylimidazolium ionic liquids that are devoid of the C-2 hydrogen. The differential time required for reaction with aromatic and aliphatic amines has offered means for selective N-t-Boc formation during inter and intramolecular competitions. Preferential N-t-Boc formation with secondary aliphatic amine has been achieved in the presence of primary aliphatic amine. Comparison of the catalytic efficiency for N-t-Boc formation with a common substrate revealed that [bmim][NTf2] is superior to the reported Lewis acid catalysts.
- Sarkar, Anirban,Roy, Sudipta Raha,Parikh, Naisargee,Chakraborti, Asit K.
-
experimental part
p. 7132 - 7140
(2011/10/08)
-
- Amination of aryl iodides using a fluorous-tagged ammonia equivalent
-
A fluorous-tagged ammonia equivalent for the Cu-catalyzed amination of aryl iodides is described in which N-Boc-protected anilines are produced in high overall yield and purity. All purification steps are performed using Fluorous SolidPhase Extraction (F-SPE) greatly simplifying and speeding up the isolation of the desired products.
- Nielsen, Simon Dalsgaard,Smith, Garrick,Begtrup, Mikael,Kristensen, Jesper L.
-
experimental part
p. 3704 - 3710
(2010/09/05)
-
- PEG-mediated facile protocol for N-Boc protection of amines
-
We have reported an efficient and eco-friendly protocol for the protection of various structurally and electronically divergent aryl and aliphatic amines using (Boc)2O in the presence of PEG-400 at room temperature. The reaction gave excellent
- Siddaiah,Basha,Padma Rao,Viplava Prasad,Suryachendra Rao
-
experimental part
p. 1127 - 1129
(2011/02/28)
-
- Amberlyst-15: a mild, efficient and reusable heterogeneous catalyst for N-tert-butoxycarbonylation of amines
-
A mild and versatile method has been developed for the chemoselective N-tert-butoxycarbonylation of amines in the presence of Amberlyst-15 under solvent-free condition. The method is general for the preparation of N-Boc derivatives of aliphatic (acyclic and cyclic) and aromatic amines.
- Kumar, K. Shiva,Iqbal, Javed,Pal, Manojit
-
experimental part
p. 6244 - 6246
(2010/01/11)
-
- CARBOXAMIDE DERIVATIVES AS ION CHANNEL MODULATORS
-
The present teachings provide compounds of Formula (I) wherein Ar, R1, R2, R3, X, p and n are defined herein. The present teachings also provide processes for producing said compounds and methods of treating a pathological condition or disorder, or alleviating a symptom thereof, using said compounds. The compounds can be useful in modulating ion channel activity including treating a variety of conditions associated with the abnormal modulation of one or more voltage-gated calcium channels.
- -
-
Page/Page column 98
(2008/12/06)
-
- ION CHANNEL MODULATORS
-
The present teachings provide carboxylic amide compounds that can modulate the activity of ion channels in a mammal. The present teachings also provide processes for producing said compounds and their pharmaceutically acceptable salts, hydrates and esters, and methods of treating a pathological condition or disorder, or alleviating a symptom thereof, using said compounds including their pharmaceutically acceptable salts, hydrates and esters. The compounds can be useful in modulating ion channel activity including treating a variety of conditions associated with the abnormal modulation of one or more voltage-gated calcium channels.
- -
-
Page/Page column 135
(2008/12/06)
-
- Nucleus- and side-chain fluorinated 3-substituted indoles by a suitable combination of organometallic and radical chemistry
-
Regioselectively fluoro-, trifluoromethyl- and trifluoromethoxy-substituted 3-methyleneindolines have been prepared using a four-step procedure involving metalation/bromination of fluorinated Boc-protected anilines, N-propargylation of the resulting o-bro
- Bellezza, Francesca,Cipiciani, Antonio,Ruzziconi, Renzo,Spizzichino, Sara
-
-
- ION CHANNEL MODULATORS
-
The present teachings provide compounds of Formula (I): and pharmaceutically acceptable salts, hydrates, and esters thereof, wherein Ar, R1, R2, R3, p, and X are defined herein. The present teachings also provide processes for producing said compounds and their pharmaceutically acceptable salts, hydrates and esters, and methods of treating a pathological condition or disorder, or alleviating a symptom thereof, using said compounds including their pharmaceutically acceptable salts, hydrates and esters. The compounds can be useful in modulating ion channel activity including treating a variety of conditions associated with the abnormal modulation of one or more voltage-gated calcium channels.
- -
-
Page/Page column 96
(2008/12/06)
-
- ION CHANNEL MODULATORS
-
The present teachings provide compounds of Formula (I) and pharmaceutically acceptable salts, hydrates, and esters thereof, wherein Ar, R1, R1', R2, R3, R4 R4', and p are defined herein. The present teachings also provide processes for producing said compounds and their pharmaceutically acceptable salts, hydrates and esters, and methods of treating a pathological condition or disorder, or alleviating a symptom thereof, using said compounds including their pharmaceutically acceptable salts, hydrates and esters. The compounds can be useful in modulating ion channel activity including treating a variety of conditions associated with the abnormal modulation of one or more voltage-gated calcium channels.
- -
-
Page/Page column 66
(2008/12/06)
-
- Tricyclic benzimidazoles and their use as metabotropic glutamate receptor modulators
-
The invention provides for a compound of formula (I) or a pharmaceutically acceptable salt thereof: wherein R1, R2, R3, A, B, D, m, n, x, and y are defined as described in the specification. The invention additionally provides a pharmaceutically composition comprising the compound of formula I, together with a method of using the same to treat or prevent neurological and psychiatric disorders. The compounds are useful in therapy related to the treatment or prevention of mGluR2 receptor-mediated disorders.
- -
-
Page/Page column 30; 35
(2008/06/13)
-
- COMPOUNDS AND COMPOSITIONS AS PROTEIN KINASE INHIBITORS
-
The invention provides a novel class of compounds, pharmaceutical compositions comprising such compounds and methods of using such compounds to treat or prevent diseases or disorders associated with abnormal or deregulated kinase activity, particularly di
- -
-
Page/Page column 34-35
(2010/11/25)
-
- Copper(II) tetrafluoroborate as a novel and highly efficient catalyst for N-tert-butoxycarbonylation of amines under solvent-free conditions at room temperature
-
Commercially available copper(II) tetrafluoroborate hydrate was found to be a highly efficient catalyst for chemoselective N-tert-butoxycarbonylation of amines with di-tert-butyl dicarbonate under solvent-free conditions and at room temperature. Various aromatic amines were protected as their N-tert-butyl carbamates in high yields and in short times. No competitive side reactions such as isocyanate, urea, and N,N-di-t-Boc formation was observed. Chemoselective N-tert-butoxycarbonylation was achieved with substrates bearing OH and SH groups. Chiral α-amino acid esters afforded the corresponding N-t-Boc derivatives in excellent yields.
- Chankeshwara, Sunay V.,Chakraborti, Asit K.
-
p. 1087 - 1091
(2007/10/03)
-
- Indium(III) halides as new and highly efficient catalysts for N-tert-butoxycarbonylation of amines
-
Indium(III) bromide and chloride efficiently catalysed the N-tert-butoxycarbonylation of amines with (Boc)2O at room temperature and under solvent-free conditions. Various aromatic, heteroaromatic and aliphatic amines were converted to N-tert-butylcarbamates in excellent yields in short times. Chiral amines, esters of α-amino acids and β-amino alcohols afforded optically pure N-t-Boc derivatives in high yields. The reactions were chemoselective and no competitive side reactions such as isocyanate, urea, and N,N-di-t-Boc formation were observed. Chemoselective conversion to N-tert-butylcarbamates took place with amino alcohols without any formation of oxazolidinones. Georg Thieme Verlag Stuttgart.
- Chankeshwara, Sunay V.,Chakraborti, Asit K.
-
p. 2784 - 2788
(2008/02/05)
-
- Facile N-tert-butoxycarbonylation of amines using La(NO3)3·6H2O as a mild and efficient catalyst under solvent-free conditions
-
Facile N-tert-butoxycarbonylation of amines is described by the treatment of various primary, secondary, benzylic and aryl amines with di-tert-butyl dicarbonate in the presence of catalytic amounts of La(NO3)3·6H2O under solvent-free conditions at room temperature to afford N-tert-butylcarbamates in excellent yields.
- Suryakiran,Prabhakar,Reddy, T. Srikanth,Rajesh,Venkateswarlu
-
p. 8039 - 8042
(2007/10/03)
-
- HClO4-SiO2 as a new, highly efficient, inexpensive and reusable catalyst for N-tert-butoxycarbonylation of amines
-
Perchloric acid adsorbed on silica-gel (HClO4-SiO2) was found to be a new, highly efficient, inexpensive and reusable catalyst for chemoselective N-tert-butoxycarbonylation of amines at room temperature and under solvent-free conditions. The Royal Society of Chemistry 2006.
- Chakraborti, Asit K.,Chankeshwara, Sunay V.
-
p. 2769 - 2771
(2008/03/28)
-
- Catalyst-free chemoselective N-tert-butyloxycarbonylation of amines in water
-
Catalyst-free N-tert-butyloxycarbonylation of amines in water is reported. The N-t-Boc derivatives were formed chemoselectively without any isocyanate, urea, N,N-di-t-Boc, and O/S-t-Boc as side products. Chiral amines, esters of α-amino acids, and β-amino alcohol afforded optically pure N-t-Boc derivatives. Amino alcohol and 2-aminophenol afforded the N-t-Boc derivative without oxazolidinone formation. Selectivity was observed during competition of aromatic amine vs aliphatic amine, amine vs amino acid ester, amine vs amino alcohol, and primary amine vs secondary amine.
- Chankeshwara, Sunay V.,Chakraborti, Asit K.
-
p. 3259 - 3262
(2007/10/03)
-
- In search of simplicity and flexibility: A rational access to twelve fluoroindolecarboxylic acids
-
All twelve indolecarboxylic acids 1-12 carrying both a fluorine substituent and a carboxy group at the benzo ring have been prepared either directly from the corresponding fluoroindoles 13-16 or from the chlorinated derivatives 22, 23 and 25 by hydrogen/metal permutation ("metalation"), or from the bromo- or iodofluoroindoles 17-20 and 26, 27, 29 and 30 by halogen/metal permutation, the organometallic intermediate being each time trapped with carbon dioxide. In most, though not all cases, the nitrogen atom in the five-membered ring had to be protected by a trialkylsilyl group. Some of the bromo- or iodofluoroindoles (26 and 27) were successfully subjected to a basicity gradient-driven selective migration of the heavy halogen. An unexpected finding on the way to the target compounds were the rigorously site-selective metalation of the 5-fluoro-N-(trialkylsilyl)indole (14b; exclusive deprotonation of the 4-position). The fluoroindoles 13-16, although previously known, were accessed more conveniently from suitably substituted nitrobenzenes using the Bartoli or the Leimgruber-Batcho method. A new and very attractive indole synthesis was elaborated consisting of the ortho-lithiation of an N-acyl-protected aniline followed by ortho-formylation, Wittig chloromethylenation and base-catalyzed cyclization accompanied by dehydrochlorination. These five consecutive steps can be contracted to a convenient one-pot protocol. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Schlosser, Manfred,Ginanneschi, Assunta,Leroux, Frederic
-
p. 2956 - 2969
(2007/10/03)
-
- N-boc protection of amines with di-tert-butyldicarbonate in water under neutral conditions in the presence of β-cyclodextrin
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A new protocol for protection of aryl and aliphatic amines was developed with (Boc)2O in the presence of β-cyclodextrin in water. A catalytic amount of β-cyclodextrin is specific for activation of amines. This procedure works well on a wide variety of both electron-rich and electron-deficient amines. Georg Thieme Verlag Stuttgart.
- Somi Reddy,Narender,Nageswar,Rama Rao
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p. 1110 - 1112
(2007/10/03)
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- Development of N-4,6-pyrimidine-N-alkyl-N′-phenyl ureas as orally active inhibitors of lymphocyte specific tyrosine kinase
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A new class of lymphocyte specific tyrosine kinase (lck) inhibitors based on an N-4,6-pyrimidine-N-alkyl-N′-phenyl urea scaffold is described. Many of these compounds showed low-nanomolar inhibition of lck kinase activity as well as IL-2 synthesis from Ju
- Maier, Jennifer A.,Brugel, Todd A.,Sabat, Mark,Golebiowski, Adam,Laufersweiler, Matthew J.,VanRens, John C.,Hopkins, Corey R.,De, Biswanath,Hsieh, Lily C.,Brown, Kimberly K.,Easwaran, Vijayasurian,Janusz, Michael J.
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p. 3646 - 3650
(2007/10/03)
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- Heterocyclic antiviral compounds
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This invention relates to piperidine derivatives of formulae Ia and Ib with substituents as defined herein useful in the treatment of a variety of disorders, including those in which the modulation of CCR5 receptors is implicated. More particularly, the present invention relates to 1-oxa-3,8-diaza-spiro[4.5]decan-2-one and 1-oxa-3,9-diaza-spiro[5.5]undecan-2-one compounds and related derivatives, to compositions containing and to uses of such derivatives. Disorders that may be treated or prevented by the present derivatives include HIV and genetically related retroviral infections (and the resulting acquired immune deficiency syndrome, AIDS), diseases of the immune system and inflammatory diseases.
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Page/Page column 44
(2008/06/13)
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- Synthesis of regiospecifically substituted quinolines from anilines
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A protocol for the synthesis of quinolines substituted on both pyridine and benzo-fused rings is reported. The method is based on the formylation of a substituted N-(tert-butoxycarbonyl)aniline followed by direct cyclisation and aromatisation of the inter
- Chelucci, Giorgio,Manca, Ilaria,Pinna, Gerard A.
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p. 767 - 770
(2007/10/03)
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- Novel cyclic amide derivatives
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Novel compounds represented by the following formula (I) that act as a ligand to sigma receptor/binding cite and a medicament comprising the same as an active ingredient: wherein X represents an alkyl group, an aryl group, a heterocyclic group or the like; Q represents a group represented by —CH2—, —CO—, —O—, —CH(OR7)— or the like wherein R7 represents a hydrogen atom, an alkyl group or the like; n represents an integer of from 0 to 5; R1 and R2 each represent a hydrogen atom, an alkyl group or the like; B represents either of the following groups: wherein R3, R4, R5, and R6 each represent a hydrogen atom, a halogen atom, an alkoxyl group or the like; m represents 1 or 2; and the ring of: represents an aromatic heterocyclic ring.
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- Electrophilic amination of carbanions with metallated t-butyl N-tosyloxycarbamate
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The reactivity of metallated t-butyl N-tosyloxycarbamate as electrophilic aminating reagent was studied.N-Boc-protected primary alkyl and aryl amines were obtained by reaction of organometallic derivatives with this reagent. - Keywords: electrophilic amin
- Greck, Christine,Bischoff, Laurent,Girard, Anne,Hajicek, Josef,Genet, Jean-Pierre
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p. 429 - 433
(2007/10/02)
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