Discovery of β-homophenylalanine based pyrrolidin-2-ylmethyl amides and sulfonamides as highly potent and selective inhibitors of dipeptidyl peptidase IV
作者:Sonja Nordhoff、Silvia Cerezo-Gálvez、Holger Deppe、Oliver Hill、Meritxell López-Canet、Christian Rummey、Meinolf Thiemann、Victor G. Matassa、Paul J. Edwards、Achim Feurer
DOI:10.1016/j.bmcl.2009.05.109
日期:2009.8
Modifications of DPP-4 inhibitor 5, that was discovered by structure based design, are described and structure–activity relationships discussed. With analogue 7k one of the most potent non-covalent inhibitors of DPP-4 reported to date (IC50 = 0.38 nM) was discovered. X-ray structure of inhibitor 7k bound to DPP-4 revealed a hydrogen bonding interaction with Q553. First successful efforts in balancing
Screening of simple N-aryl and N-heteroaryl pyrrolidine amide organocatalysts for the enantioselective aldol reaction of acetone with isatin
作者:Michael Kinsella、Patrick G. Duggan、Claire M. Lennon
DOI:10.1016/j.tetasy.2011.07.016
日期:2011.7
We have screened a range of simple N-aryl and N-heteroaryl pyrrolidine amide organocatalysts incorporating N-pyridyl and N-quinolinyl groups in the synthetically useful aldol reaction of isatin with acetone. The 'reverse amide' N-pyridyl pyrrolidinylmethyl amide catalysts proved highly catalytically active but gave disappointing enantioselectivities. However, an N-3-pyridyl prolinamide catalyst gave the aldol adduct in high yields and high enantioselectivity with up to 72% ee of the (S)-isomer. Conditions were optimised for this catalyst and in particular an additive screen identified a link between the pK(a) of the acid additive and the yield and enantioselectivity. An N-arylsulfonamide prolinamide was also identified as a catalyst for this reaction giving the (R)-enantiomer in 68% ee. (C) 2011 Elsevier Ltd. All rights reserved.