Synthesis and radical scavenging activity of 3,3-dialkyl-3,4-dihydro-isoquinoline 2-oxides
摘要:
The syntheses and antioxidant activities of several cyclic nitrones related to phenyl t-butyl nitrone (PBN) are described. These nitrones may act as radical scavengers and have potential uses in the treatment of stroke and septic shock. (C) 1996 Elsevier Science Ltd
Disclosed are novel compounds of the formula (I) or a pharmaceutically acceptable salt or solvate thereof, wherein R1, R2, R3, R4 and X are as defined in the specification. Also disclosed are pharmaceutical compositions comprising the compounds of formula (I). Also disclosed are methods of treating cognitive or neurodegenerative diseases such as Alzheimer's disease. Also disclosed are methods of treating a cognitive or neurodegenerative disease comprising administering to a patient I need of such treatment a combination of at least one compound of formula (I) and at least one compound selected from the group consisting of β-secretase inhibitors other than those of formula (I), HMG-CoA reductase inhibitors, gamma-secretase inhibitors, non-steroidal anti-inflammatory agents, N-methyl-D-aspartate receptor antagonists, cholinesterase inhibitors and anti-amyloid antibodies.
Cross-coupling reactions between 2-methyl-2-propen-1-ol and various boronic acids are used to obtain aromatic-(2-methylallyl) derivatives. However, deboronation or isomerization side reactions may occur for several boronic acids. We describe herein the synthesis of original alkenes with good yields under mild reaction conditions that decrease these side reactions. The scope of this environmentally benign reaction is thereby extended to a wide variety of boronic acids. A mechanistic study was conducted and suggested a plausible catalytic cycle mechanism, pointing to the importance of the Lewis acidity of the boronic acid used.
Rhodium-Catalyzed, Enantioselective Hydroacylation of <i>ortho</i>-Allylbenzaldehydes
作者:Kirsten F. Johnson、Adam C. Schmidt、Levi M. Stanley
DOI:10.1021/acs.orglett.5b02559
日期:2015.10.2
The development of a rhodiumcatalyst for endo- and enantioselective hydroacylation of ortho-allylbenzaldehydes is reported. A catalyst generated in situ from [Rh(COD)Cl]2, (R)-DTBM-SEGPHOS, and NaBARF promotes the desired hydroacylation reactions and minimizes the formation of byproducts from competitive alkene isomerization and ene/dehydration pathways. These rhodium-catalyzed processes generate
Photoinduced Dearomatizing Three‐Component Coupling of Arylphosphines, Alkenes, and Water
作者:Yusuke Masuda、Hiromu Tsuda、Masahiro Murakami
DOI:10.1002/anie.202013215
日期:2021.2.15
A unique photoinduced reaction that couples a triarylphosphine, an alkene, and water to produce 2‐(cyclohexa‐2,5‐dienyl)ethylphosphine oxide is reported herein. The alkene inserts into a C(aryl)−P bond of the arylphosphine, the aryl ring is dearomatized into the cyclohexadienyl ring, and the phosphorus is oxidized. The three components are all readily available, and their intermolecular coupling significantly
Ligandless Iron-Catalyzed Desulfinylative CâC Allylation Reactions using Grignard Reagents and Alk-2-enesulfonyl Chlorides
作者:Chandra M. R. Volla、Dean MarkovicÌ、Srinivas Reddy Dubbaka、Pierre Vogel
DOI:10.1002/ejoc.200900927
日期:2009.12
regioselectivity of these allylations was studied by using sulfonyl chlorides 3 and 4 with aryl Grignard reagents. The scope of these allylations was further extended by the coupling of ester-substituted alk-2-enesulfonylchloride 10 with aromatic Grignard reagents. Symmetrical products were synthesized by double C-C allylation with the use of 2-methylidenepropane-1,3-disulfonyl chloride (12). ((C) Wiley-VCH