7-Oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridines as Novel Inhibitors of Human Eosinophil Phosphodiesterase
摘要:
High-throughput file screening against inhibition of human lung PDE4 led to the discovery of 3-ethyl-1-(4-fluorophenyl)-6-phenyl-7-oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine (11) as a novel PDE4 inhibitor. Subsequent SAR development, using an eosinophil PDE assay, led to analogues up to 50-fold more potent than 11 with IC50 values of 0.03-1.6 mu M. One such compound, CP-220,629 (22) (IC50 = 0.44 mu M), was efficacious in the guinea pig aerosolized antigen induced airway obstruction assay (ED50 2.0 mg/kg, po) and demonstrated a significant reduction in eosinophil (55%), neutrophil (65%), and IL-1 beta (82%) responses to antigen challenge in atopic monkeys (10 mg/kg, po).
Combining Transition Metal Catalysis with Radical Chemistry: Dramatic Acceleration of Palladium-Catalyzed CH Arylation with Diaryliodonium Salts
作者:Sharon R. Neufeldt、Melanie S. Sanford
DOI:10.1002/adsc.201200738
日期:2012.12.14
This paper describes a photoredox palladium/iridium-catalyzed C-H arylation with diaryliodonium reagents. Details of the reaction optimization, substrate scope, and mechanism are presented along with a comparison to a related method in which aryldiazonium salts are used in place of diaryliodonium reagents. The unprecedentedly mild reaction conditions (25 masculineC in methanol), the requirement for
Synthetic and Mechanistic Studies of Pd-Catalyzed C−H Arylation with Diaryliodonium Salts: Evidence for a Bimetallic High Oxidation State Pd Intermediate
作者:Nicholas R. Deprez、Melanie S. Sanford
DOI:10.1021/ja904116k
日期:2009.8.12
influence of the arylating reagent on the reaction rate, and establish the intra- and intermolecular 1 degree H/D kinetic isotope effect. On the basis of these studies, this transformation is proposed to proceed via turnover-limiting oxidation of the Pd dimer [Pd(N~C)(OAc)](2) (N~C = 3-methyl-2-phenylpyridine) by [Mes-I-Ph]BF(4). This mechanism implicates a bimetallic high oxidation state Pd species
Room-Temperature C–H Arylation: Merger of Pd-Catalyzed C–H Functionalization and Visible-Light Photocatalysis
作者:Dipannita Kalyani、Kate B. McMurtrey、Sharon R. Neufeldt、Melanie S. Sanford
DOI:10.1021/ja208068w
日期:2011.11.23
This communication describes the development of a room-temperature ligand-directed C-H arylation reaction using aryldiazoniumsalts. This was achieved by the successful merger of palladium-catalyzed C-H functionalization and visible-lightphotoredoxcatalysis. The new method is general for a variety of directing groups and tolerates many common functional groups.
Rhodium(III)-Catalyzed C-H Vinylation of Arenes: Access to Functionalized Styrenes
作者:Jun Zhou、Xin Li、Gang Liao、Bing-Feng Shi
DOI:10.1002/cjoc.201800354
日期:2018.12
An effective method has been developed for Rh(III)‐catalyzed direct vinylation of arenes to give functionalized styrenes, using vinyltriethoxysilane as a convenient and inexpensive vinyl source. A wide variety of substrates, including 1‐aryl‐2‐pyrrolidinones, anilines, benzamides and ketones, were compatible with this reaction. Moreover, this method can be applied to the two‐step synthesis of functionalized
Mild and Efficient Cobalt-Catalyzed Cross-Coupling of Aliphatic Amides and Aryl Iodides in Water
作者:Yong-Chua Teo、Bryan Tan
DOI:10.1055/s-0034-1380724
日期:——
convenient protocol for the C–N cross-coupling of aliphatic amides and iodobenzene is demonstrated using a simple and inexpensive Co(C2O4)·2H2O/N,N′-dimethylethylenediamine (DMEDA) catalytic system in water. Good yields of N-arylated products were isolated (up to 85%) and the protocol has been successfully applied to the synthesis of the anticancer drug, flutamide.