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" no prazo de Papéis
Ning Zhu et al.
Journal of combinatorial chemistry, 12(4), 531-540 (2010-06-01)
The thiol-disulfide dynamic interchange reaction mediated by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was extensively studied. By this synthetic method sulfides can be prepared successfully within seconds in high yields at room temperature from stable and readily available disulfides and an alkylating agent. The
Ana Pascual et al.
Biomacromolecules, 16(4), 1169-1178 (2015-03-13)
In this study, a new family of broad-spectrum antimicrobial polycarbonate hydrogels has been successfully synthesized and characterized. Tertiary amine-containing eight-membered monofunctional and difunctional cyclic carbonates were synthesized, and chemically cross-linked polycarbonate hydrogels were obtained by copolymerizing these monomers with a
Mathieu Arnould et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 19(37), 12249-12253 (2013-08-21)
Dancing with diversity: The synthesis of diverse pyrido[2',1':2,3]imidazo[4,5-b]quinolines bearing several substitution patterns was developed based on combining a multicomponent reaction (Groebke-Blackburn-Bienaymé reaction) with an original cyclization as a secondary transformation (see scheme; DBU = 1,8-diazabicyclo[5.4.0]undec-7-ene).
H. Oediger et al.
Synthesis, 591-591 (1972)
Dengyou Zhang et al.
Chemical communications (Cambridge, England), 48(23), 2909-2911 (2012-02-07)
A practical Pd(PPh(3))(4)/DBU catalytic system for the synthesis of pharmaceutically relevant aminopyridine nitrile intermediates, as well as a variety of other aryl nitriles using non-toxic K(4)[Fe(CN)(6)] has been developed. The key features of our new protocol for cyanation lie in
Naoto Utsumi et al.
Organic letters, 10(16), 3405-3408 (2008-07-18)
Direct organocatalytic Mannich-type reactions of thioesters provide for the expedient and diastereoselective synthesis of protected beta-amino acids. A variety of thioesters were found to be reactive with different imines under mild conditions to provide beta-amino acids in good yields. This
N. Ono et al.
Bulletin of the Chemical Society of Japan, 52, 1716-1716 (1979)
Shyam S Verma et al.
Carbohydrate research, 341(11), 1930-1937 (2006-05-16)
DBU catalyzed condensation of 3-O-benzyl(methyl)-5,6-dideoxy-1,2-O-isopropylidene-beta-L-threo-hept-4-enofuranuronates with different aldehydes produces the corresponding 3-O-benzyl(methyl)-6-carbethoxy-5,6-dideoxy-1,2-O-isopropylidene-7-phenyl-beta-L-threo-hept-4-enofuranoses. The latter on treatment with methanesulfonyl chloride followed by DBU catalyzed E2 reaction of the methanesulfonyloxy intermediates gave the respective 3-O-benzyl(methyl)-6-carbethoxy-5,6,7-trideoxy-1,2-O-isopropylidene-7-phenyl-beta-L-threo-hept-4,6-dienofuranose in moderate to good yields.
Matthew O'Reilly et al.
Dalton transactions (Cambridge, England : 2003), (31)(31), 6092-6095 (2010-05-08)
With the new chiral phosphine ligand DBUP, obtained from DBU and Ph(2)PCl, a remarkable anion effect was observed on the diastereoselective formation of the bischelated complexes [Ni(DBUP)(2)](X)(n) (X = Cl, Br, n = 2; X = NiCl(4), n = 1)
Claude Larrivée-Aboussafy et al.
Organic letters, 12(2), 324-327 (2009-12-18)
1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) has been found to catalyze the amidation of acyl imidazoles. The rate acceleration is especially evident with traditionally unreactive, electron-deficient anilines. DBU is readily available and offers safety and cost advantages over more commonly employed catalysts such as
Joachim B Havla et al.
Toxicology in vitro : an international journal published in association with BIBRA, 24(3), 849-853 (2009-12-17)
Tissue engineering of autologous cartilage transplants is suggested as a new approach in reconstruction of external auricular deformities. 1.6-Hexanediol (HD), 1.8-diazabicyclo[5.4.0]undec-7-ene (DBU) and 6-hydroxyhexanoic acid (HHA) are matrices of the open-pored polyurethane three-dimensional scaffold. Since these bioresorbable materials may interact
Cédric G Jaffredo et al.
Macromolecular rapid communications, 33(22), 1938-1944 (2012-08-14)
Basic organocatalysts of the guanidine (1,5,7-triazabicyclo[4.4.0]dec-5-ene, TBD), amidine (1,8-diazabicyclo[5.4.0]-undec-7-ene, DBU), and phosphazene (2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2diazaphosphorine, BEMP) type do effectively polymerize β-butyrolactone (BL). Poly(3-hydroxybutyrate)s (PHBs) with controlled molecular features, that is, controlled molar masses, narrow molar mass distributions, and well-defined functional end groups
Xiuzhao Yu et al.
Chemical communications (Cambridge, England), 48(33), 4002-4004 (2012-03-17)
An efficient, metal free approach to highly substituted 2-pyrrolines by DBU-catalyzed tandem additions (a formal [3+2] cycloaddition) of electron-deficient 1,3-conjugated enynes and 2-aminomalonates under mild conditions was developed.
1, 8-Diazabicyclo [5.4. 0] undec-7-ene (DBU) as ligand for atom transfer radical polymerization (ATRP)
Fournier D, et al.
European Polymer Journal, 41(7), 1576-1581 (2005)
1, 8-Diazabicyclo [5.4. 0] undec-7-ene (DBU)-promoted efficient and versatile aza-Michael addition.
Yeom C-E, et al.
Tetrahedron, 63(4), 904-909 (2007)
Jack W Blount et al.
Journal of agricultural and food chemistry, 63(8), 2233-2240 (2015-02-12)
Grape seed polyphenolic extract (GSPE) rich in the flavan-3-ols (+)-catechin and (-)-epicatechin beneficially modulates Alzheimer's Disease phenotypes in animal models. The parent molecules in the extract are converted to a series of methylated and glucuronidated derivatives. To fully characterize these
Gui-Ling Zhao et al.
Organic letters, 7(20), 4527-4530 (2005-09-24)
[reaction: see text] DBU-catalyzed reactions of salicylic aldehydes with 3-methylpenta-3,4-dien-2-one, 3-benzylpenta-3,4-dien-2-one, or ethyl 2-methylbuta-2,3-dienoate gave the corresponding functionalized 2H-1-chromenes in good to excellent yields and good diastereoselectivities in some cases in DMSO, respectively.
Kristin E Price et al.
Organic letters, 11(9), 2003-2006 (2009-04-04)
A mild, high-yielding, and practical protocol for the direct amidation of alkyl cyanoacetates using DBU is presented. This method eliminates the need for activation of cyanoacetic acid and/or high temperatures. It has been applied to the large-scale synthesis of CP-690,550-10
Wen-Chung Shieh et al.
The Journal of organic chemistry, 67(7), 2188-2191 (2002-04-02)
1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) is an effective nucleophilic catalyst for carboxylic acid esterification with dimethyl carbonate (DMC). The reaction pathway of this new class of nucleophilic catalysis has been studied. A plausible, multistep mechanism is proposed, which involves an initial N-acylation of
Young H Lim et al.
ACS nano, 9(2), 1995-2008 (2015-01-27)
The development of well-defined polymeric nanoparticles (NPs) as delivery carriers for antimicrobials targeting human infectious diseases requires rational design of the polymer template, an efficient synthetic approach, and fundamental understanding of the developed NPs, e.g., drug loading/release, particle stability, and
Claudia Scholz et al.
ChemMedChem, 9(9), 2104-2110 (2014-02-08)
The optimization of synthetic carriers for gene transfer remains a major challenge. Cationic polymers such as polyethylenimine (PEI) often show increasing gene transfer activity with increasing molecular weight, but this favorable effect is accompanied by an undesired increase in cytotoxicity.
C.G. Rao
Organic preparations and procedures international, 12, 225-225 (1980)
Wim L Noorduin et al.
Angewandte Chemie (International ed. in English), 48(51), 9600-9606 (2009-12-01)
A century ago Wilhelm Ostwald received the Nobel Prize for Chemistry. Although Ostwald was never significantly involved with the phenomenon of chirality, one of his discoveries, Ostwald ripening, is thought to be involved in a recently discovered method in which
Yang Lu et al.
Journal of chromatographic science, 52(9), 1109-1120 (2013-10-11)
Cyclodextrins (CDs) and their derivatives have been one of the most popular and successful chiral additives used in electrokinetic chromatography because of the presence of multiple chiral centers, which leads to multiple chiral interactions. However, there has been relatively less
Chiara Samorì et al.
Bioresource technology, 101(9), 3274-3279 (2010-01-15)
Lipid extraction is a critical step in the development of biofuels from microalgae. Here a new procedure was proposed to extract hydrocarbons from dried and water-suspended samples of the microalga Botryococcus braunii by using switchable-polarity solvents (SPS) based on 1,8-diazabicyclo-[5.4.0]-undec-7-ene
Masahiro Yoshida et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 18(49), 15578-15581 (2012-11-09)
This'll fix it: efficient fixation of atmospheric CO(2) has been achieved by the reaction of propargylic amines with a silver/DBU dual-catalyst system. Various oxazolidinones were synthesized in moderate to good yields by using substituted propargylic amines.
Wanli Chen et al.
The Journal of organic chemistry, 77(3), 1585-1591 (2012-01-19)
DBU-promoted cyclization of ortho-(3-hydroxy-1-alkynyl)benzamide is presented, providing an efficient method for the synthesis of trans-3,4-dihydroisoquinolin-1(2H)-ones and (E)-4-(1-alkenyl)isoquinolin-1(2H)-ones under mild conditions.
Highly efficient organosuperbase-catalyzed Mannich-type reactions of sulfonylimidates with imines: successful use of aliphatic imines as substrates and a unique reaction mechanism.
Junya Nakano et al.
Angewandte Chemie (International ed. in English), 51(38), 9525-9529 (2012-08-30)
Lun-Zhi Dai et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 13(13), 3701-3706 (2007-01-20)
Reactions of salicylaldehydes with ethyl buta-2,3-dienoate or penta-3,4-dien-2-one catalyzed by a catalytic amount of potassium carbonate produce the corresponding 2 H-chromene products in moderate to good yields under mild conditions. A plausible reaction mechanism is discussed in the light of
Shigeo Hayashi et al.
Journal of enzyme inhibition and medicinal chemistry, 29(6), 846-867 (2014-02-13)
Because of the pivotal role of cyclooxygenase (COX) in the inflammatory processes, non-steroidal anti-inflammatory drugs (NSAIDs) that suppress COX activities have been used clinically for the treatment of inflammatory diseases/syndromes; however, traditional NSAIDs exhibit serious side-effects such as gastrointestinal damage
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