- Copper-Catalyzed [3+2] Cycloaddition Reactions of Isocyanoacetates with Phosphaalkynes to Prepare 1,3-Azaphospholes
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A novel copper-catalyzed synthetic method is described for phosphorous- and nitrogen-containing heterocycles such as 1,3-azaphospholes. Cycloaddition reactions of various isocyanoacetates with phosphaalkynes in the presence of copper bromide, bis(diphenylphosphino)methane (dppm), and potassium carbonate afford the corresponding 1,3-azaphospholes in high yields with complete selectivity. Some dppm-bridged dicopper complexes were identified as active species for the formation of 1,3-azaphospholes.
- Liang, Wenbin,Nakajima, Kazunari,Sakata, Ken,Nishibayashi, Yoshiaki
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- BENZODIAZEPINE DERIVATIVES, COMPOSITIONS, AND METHODS FOR TREATING COGNITIVE IMPAIRMENT
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This invention relates to benzodiazepine derivatives, compositions comprising therapeutically effective amounts of those derivatives and methods of using those derivatives or compositions in treating cognitive impairment associated with CNS disorders. It also relates to the use of an α5-containing GABAA receptor agonist (e.g., an α5-containing GABAA receptor positive allosteric modulator) in treating cognitive impairment associated with CNS disorders in a subject in need or at risk thereof, including age-related cognitive impairment, Mild Cognitive Impairment (MCI), amnestic MCI, Age-Associated Memory Impairment, Age Related Cognitive Decline, dementia, Alzheimer's Disease(AD), prodromal AD, PTSD, schizophrenia, bipolar disorder, ALS, cancer-therapy-related cognitive impairment, mental retardation, Parkinson's disease, autism spectrum disorders, fragile X disorder, Rett syndrome, compulsive behavior, and substance addiction. It also relates to the use of an α5-containing GABAA receptor agonist (e.g., an α5-containing GABAA receptor positive allosteric modulator) in treating brain cancers (including brain tumors, e.g., medulloblastomas), and cognitive impairment associated therewith.
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Paragraph 0617
(2020/01/11)
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- BENZODIAZEPINE DERIVATIVES, COMPOSITIONS, AND METHODS FOR TREATING COGNITIVE IMPAIRMENT
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This invention relates to benzodiazepine derivatives, compositions comprising therapeutically effective amounts of those benzodiazepine derivatives and methods of using those derivatives or compositions in treating cognitive impairment associated with central nervous system (CNS) disorders. In particular, it relates to the use of a α5-containing GABAA receptor agonist (e.g., a α5-containing GABAA receptor positive allosteric modulator) as described herein in treating cognitive impairment associated with central nervous system (CNS) disorders in a subject in need or at risk thereof, including, without limitation, subjects having or at risk for age-related cognitive impairment, Mild Cognitive Impairment (MCI), amnestic MCI (aMCI), Age-Associated Memory Impairment (AAMI), Age Related Cognitive Decline (ARCD), dementia, Alzheimer's Disease(AD), prodromal AD, post traumatic stress disorder (PTSD), schizophrenia, bipolar disorder, amyotrophic lateral sclerosis (ALS), cancer-therapy-related cognitive impairment, mental retardation, Parkinson's disease (PD), autism spectrum disorders, fragile X disorder, Rett syndrome, compulsive behavior, and substance addiction. It also relates to the use of a α5-containing GABAA receptor agonist (e.g., a α5-containing GABAA receptor positive allosteric modulator) as described herein in treating brain cancers (including brain tumors, e.g., medulloblastomas), and cognitive impairment associated therewith.
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Paragraph 1599
(2018/07/05)
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- BENZODIAZEPINE DERIVATIVES, COMPOSITIONS, AND METHODS FOR TREATING COGNITIVE IMPAIRMENT
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This invention relates to benzodiazepine derivatives, compositions comprising therapeutically effective amounts of those benzodiazepine derivatives and methods of using those derivatives or compositions in treating cognitive impairment associated with central nervous system (CNS) disorders. In particular, it relates to the use of a α5- containing GABAA receptor agonist (e.g., a α5-containing GABAA receptor positive allosteric modulator) as described herein in treating cognitive impairment associated with central nervous system (CNS) disorders in a subject in need or at risk thereof, including, without limitation, subjects having or at risk for age-related cognitive impairment, Mild Cognitive Impairment (MCI), amnestic MCI (aMCI), Age- Associated Memory Impairment (AAMI), Age Related Cognitive Decline (ARCD), dementia, Alzheimer' s Disease(AD), prodromal AD, post traumatic stress disorder (PTSD), schizophrenia, bipolar disorder, amyotrophic lateral sclerosis (ALS), cancer-therapy-related cognitive impairment, mental retardation, Parkinson' s disease (PD), autism spectrum disorders, fragile X disorder, Rett syndrome, compulsive behavior, and substance addiction.
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Paragraph 0539
(2017/01/02)
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- Enantioselective synthesis of (-)-chloramphenicol via silver-catalysed asymmetric isocyanoacetate aldol reaction
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The highly enantio- and diastereoselective aldol reaction of isocyanoacetates catalysed by Ag2O and cinchona-derived amino phosphines applied to the synthesis of (-)- and (+)-chloramphenicol is described. The concise synthesis showcases the utility of this catalytic asymmetric methodology for the preparation of bioactive compounds possessing α-amino-β-hydroxy motifs.
- Franchino, Allegra,Jakubec, Pavol,Dixon, Darren J.
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- A Straightforward Approach towards Cyclic Photoactivatable Tubulysin Derivatives
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The development of a new photolabile protecting group containing an additional allyl functionality allows the synthesis of cyclic photoactivatable natural products. Cyclization occurs between the allyl moiety in the protecting group and a second double bond in the target molecule by means of ring-closing metathesis. Cyclization should increase the metabolic stability towards proteases. On the other hand, the conformational change should cause diminished biological activity. As illustrated for tubulysin derivatives, cyclic and photoactivatable drug candidates can easily be obtained in only two steps from simple building blocks through Ugi reaction and ring-closing metathesis. The photolabile protecting group is introduced by means of the isocyanide component during the Ugi reaction.
- Hoffmann, Judith,Kazmaier, Uli
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p. 11356 - 11360
(2016/02/18)
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- Porphyrins with exocyclic rings. 11.1 Synthesis and characterization of phenanthroporphyrins, a new class of modified porphyrin chromophores
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To obtain insights into the factors that influence the electronic spectra of conjugated porphyrin systems, a series of porphyrins with fused phenanthrene subunits have been synthesized. 9-Nitrophenanthrene reacted with esters of isocyanoacetic acid in the presence of DBU in THF to give a series of phenanthro[9,10-c]pyrroles 14 in good to excellent yields, and subsequent acid-catalyzed condensation with various (acetoxymethyl)pyrroles 18 gave six examples of dipyrryl-methanes 17 that incorporate a fused phenanthrene ring. Cleavage of the benzyl esters from 17a by hydrogenolysis over 10% Pd/C gave the corresponding dicarboxylic acid 24 and this condensed with diformyldipyrrylmethanes 22 under modified MacDonald '2 + 2' condensation conditions to afford the monophenanthroporphyrins 19 and 20. Dipyrrylmethanes 17d and 17f with mixed benzyl and tert-butyl ester moieties were converted into the related formyl dipyrrylmethanecarboxylic acids 29, and subsequent head-to-tail self-condensation in the presence of p-toluenesulfonic acid yielded two examples of opp-diphenanthroporphyrins 27. Reaction of phenanthropyrroles 14 with dimenthoxymethane and p-toluenesulfonic acid in acetic acid afforded the symmetrical dipyrrl-methanes 31, and following cleavage of the ester moieties and MacDonald condensation with dialdehyde 22b, the adj-diphenanthroporphyrin 30 was isolated in moderate yield. Metal chelates of the mono-, opp-di, and adj-diphenanthroporphyrin systems were also prepared, and the electronic spectra for these modified porphyrin systems and their nickle(II), copper(II), and zinc complexes were examined. Surprisingly, the UV-vis absorptions were only slightly shifted to higher wavelengths than those for octaalkylporphyrins. Reduction of ethyl ester 14a with lithium aluminum hydride gave an unstable carbinol, and subsequent tetramerization in the presence of BF3 etherate and oxidation with DDQ afforded the tetraphenanthroporphyrin 10. The free base porphyrin was virtually insoluble in organic solvents, but protonation with TFA gave a soluble dication 10H22+ with a strong Soret band at 482 nm and two weaker absorptions at 615 and 668 nm. The bathochromic shifts for 10H22+ are far more significant than those observed for the mono- and diphenanthroporphyrin structures, although again somewhat less than might have been expected for this extraordinarily high degree of ring fusion.
- Novak, Bennett H.,Lash, Timothy D.
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p. 3998 - 4010
(2007/10/03)
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- Dehydration of formamides using the Burgess Reagent: A new route to isocyanides
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The Burgess Reagent readily converts formamides into isocyanides in high yields and is particularly effective for substrates containing halide sensitive trimethylsilyl ether groups.
- Creedon, Siobhan M.,Crowley, H. Kevin,McCarthy, Daniel G.
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p. 1015 - 1017
(2007/10/03)
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