Catalytic Coupling of Arene C–H Bonds and Alkynes for the Synthesis of Coumarins: Substrate Scope and Application to the Development of Neuroimaging Agents
摘要:
C-H bond functionalization offers strategically novel approaches to complex organic compounds. However, many C-H functionalization reactions suffer from poor compatibility with Lewis basic functional groups, especially amines, which are often essential for biological activity. This study describes a systematic examination of the substrate scope of catalytic hydroarylation in the context of complex amino coumarin synthesis. The choice of substrates was guided by the design and development of the next generation of fluorescent false neurotransmitters (FFNs), neuroimaging probes we recently introduced for optical imaging of neurotransmission in the brain. Comparison of two mild protocols using catalytic PtCl4 or Au(PPh3)Cl/AgSbF6 revealed that each method has a broad and mutually complementary substrate scope. The relatively less active platinum system out-performed the gold catalyst with indole substrates lacking substitution at the C-3 position and provided higher regioselectivity in the case of carbazole-based substrates. On the other hand, the more active gold catalyst demonstrated excellent functional group tolerance, and the ability to catalyze the formation of strained, helical products. The development of these two protocols offers enhanced substrate scope and provides versatile synthetic tools required for the structure-activity examination of FFN neuroimaging probes as well as for the synthesis of complex coumarins in general.
[EN] DEVELOPMENT OF FLUOROGENIC SUBSTRATES FOR MONOAMINE OXIDASES (MAO-A AND MAO-B) [FR] MISE AU POINT DE SUBSTRATS FLUOROGENES DESTINES AUX MONOAMINE OXYDASES (MAO-A AND MAO-B)
Development of Fluorogenic Substrates For Monoamine Oxidases (Mao-A and Mao-B)
申请人:Chen Gong
公开号:US20080194522A1
公开(公告)日:2008-08-14
The present invention relates to compounds useful for detecting the activity of monoamine oxidases, compounds useful for competitively inhibiting monoamine oxidases, for determining inhibitors of monoamine oxidases and compounds useful for treating monoamine oxidase-related nervous system pathologies, as well as pharmaceutical compositions and methods of manufacture thereof.
[EN] DEVELOPMENT OF FLUOROGENIC SUBSTRATES FOR MONOAMINE OXIDASES (MAO-A AND MAO-B)<br/>[FR] MISE AU POINT DE SUBSTRATS FLUOROGENES DESTINES AUX MONOAMINE OXYDASES (MAO-A AND MAO-B)
申请人:F NEW YORK THE TRUSTEES OF COL
公开号:WO2006026368A3
公开(公告)日:2006-08-31
Catalytic Coupling of Arene C–H Bonds and Alkynes for the Synthesis of Coumarins: Substrate Scope and Application to the Development of Neuroimaging Agents
作者:Paul A. Vadola、Dalibor Sames
DOI:10.1021/jo3006842
日期:2012.9.21
C-H bond functionalization offers strategically novel approaches to complex organic compounds. However, many C-H functionalization reactions suffer from poor compatibility with Lewis basic functional groups, especially amines, which are often essential for biological activity. This study describes a systematic examination of the substrate scope of catalytic hydroarylation in the context of complex amino coumarin synthesis. The choice of substrates was guided by the design and development of the next generation of fluorescent false neurotransmitters (FFNs), neuroimaging probes we recently introduced for optical imaging of neurotransmission in the brain. Comparison of two mild protocols using catalytic PtCl4 or Au(PPh3)Cl/AgSbF6 revealed that each method has a broad and mutually complementary substrate scope. The relatively less active platinum system out-performed the gold catalyst with indole substrates lacking substitution at the C-3 position and provided higher regioselectivity in the case of carbazole-based substrates. On the other hand, the more active gold catalyst demonstrated excellent functional group tolerance, and the ability to catalyze the formation of strained, helical products. The development of these two protocols offers enhanced substrate scope and provides versatile synthetic tools required for the structure-activity examination of FFN neuroimaging probes as well as for the synthesis of complex coumarins in general.