- Three-component asymmetric catalytic ugi reaction - Concinnity from diversity by substrate-mediated catalyst assembly
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The first chiral catalyst for the three-component Ugi reaction was identified as a result of a screen of a large set of different BOROX catalysts. The BOROX catalysts were assembled in situ from a chiral biaryl ligand, an amine, water, BH3×SMe2, and an alcohol or phenol. The catalyst screen included 13 different ligands, 12 amines, and 47 alcohols or phenols. The optimal catalyst system (LAP 8-5-47) provided α-amino amides from an aldehyde, a secondary amine, and an isonitrile with excellent asymmetric induction. The catalytically active species is proposed to be an ion pair that consists of the chiral boroxinate anion and an iminium cation. Harmonious arrangement of parts: A screen of BOROX catalysts that were generated in situ from 13 different ligands and 47 alcohols led to the identification of an effective combination for the catalytic asymmetric three-component Ugi reaction. Experimental results suggest that the catalyst is a chiral polyborate anion, which then forms an ion pair with the iminium cation that is generated from aldehyde and secondary amine.
- Zhao, Wenjun,Huang, Li,Guan, Yong,Wulff, William D.
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supporting information
p. 3436 - 3441
(2014/04/03)
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- LYSOPHOSPHATIDIC ACID RECEPTOR ANTAGONISTS
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Compounds, methods of making such compounds, pharmaceutical compositions and medicaments comprising such compounds, and methods of using such compounds to treat, prevent or diagnose diseases, disorders, or conditions associated with one or more of the lysophosphatidic acid receptors are provided.
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Paragraph 0635
(2013/03/26)
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- 4-[6-(2-Aminoethyl)naphthalen-2-yl]benzonitriles are potent histamine H3 receptor antagonists with high CNS penetration
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4-[6-(2-Tertiaryaminoethyl)naphthalen-2-yl]benzonitriles are conformationally constrained histamine H3 receptor antagonists with high potency and selectivity. The analogs were designed around a naphthalene core, with the goal of enhancing lipop
- Black, Lawrence A.,Nersesian, Diana L.,Sharma, Padam,Ku, Yi-Yin,Bennani, Youssef L.,Marsh, Kennan C.,Miller, Thomas R.,Esbenshade, Timothy A.,Hancock, Arthur A.,Cowart, Marlon
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p. 1443 - 1446
(2007/10/03)
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- An expedient and multikilogram synthesis of a naphthalenoid H3 antagonist
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A facile and scaleable synthesis of potent and selective histamine H3 receptor antagonist 1 is described, starting from commercially available 6-bromo-naphthalene-2-carboxylic acid methyl ester 3a. The key intermediate, 2-(6-bromonaphthalen-2-yl)ethanol 5 was prepared in good yield (78%) and purity (99%) via a one-carbon homologation of 3a. The coupling of 5 with pyridazinone 12 was accomplished effectively by a copper-catalyzed cross-coupling reaction. Activation of the hydroxyl group of 4, followed by displacement reaction with 2(R)-methylpyrrolidine 13, afforded the free base of 1, which was subsequently converted to its corresponding salt The new process consisted of eight chemical steps and one salt formation step and required no Chromatographic purification throughout the synthesis. It has been successfully implemented on pilot plant scale to prepare over 10 kg quantities of the target compound 1 in 43% overall yield in high purity (99%) and with the desired physical properties.
- Pu, Yu-Ming,Ku, Yi-Yin,Grieme, Timothy,Black, Lawrence A.,Bhatia, Ashok V.,Cowart, Marion
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p. 1004 - 1009
(2012/12/30)
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- Bicyclic-substituted amines as histamine-3 receptor ligands
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Compounds of formula (I) are useful in treating conditions or disorders prevented by or ameliorated by histamine-3 receptor ligands. Also disclosed are pharmaceutical compositions comprising the histamine-3 receptor ligands and methods for using such comp
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Page/Page column 30
(2008/06/13)
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- Antihyperglycemic Activity of Novel Naphthalenyl 3H-1,2,3,5-Oxathiadiazole 2-Oxides
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A series of naphthalenyl 3H-1,2,3,5-oxathiadiazole 2-oxides was prepared and tested for antihyperglycemic activity in the db/db mouse, a model for type 2 (non-insulin dependent) diabetes mellitus.Substitution at the 1-,5-, or 8-positions of the naphthalene ring with a halogen was found to be beneficial to antihyperglycemic activity. 4--3H-1,2,3,5-oxathiadiazole 2-oxide (45), one of the most potent compounds in this series, was selected for further pharmacological evaluation.
- Ellingboe, John W.,Lombardo, Louis J.,Alessi, Thomas R.,Nguyen, Thomas T.,Guzzo, Frieda,et al.
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p. 2485 - 2493
(2007/10/02)
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