623577-33-3Relevant articles and documents
Consecutive Three-Component Coupling-Addition Synthesis of β-Amino Enoates and 3-Hydroxypyrazoles via Ethyl 3-Arylpropiolates
Niedballa, Jonas,Reiss, Guido J.,Müller, Thomas J. J.
supporting information, p. 5019 - 5024 (2020/07/24)
Two consecutive three-component syntheses furnishing β-amino enoates or 3-hydroxypyrazoles based upon the Sonogashira alkynylation of aryl iodides and ethyl propiolate were established in mostly excellent yields. The ethyl 3-arylpropiolate intermediates are Michael systems which are suited for concatenation with conjugate addition or cyclocondensation giving access to libraries of 21 different β-amino enoates and 17 different 3-hydroxypyrazoles. The rotational barrier of β-pyrrolidino enoates was assessed by studying the coalescence of pyrrolidinyl protons in VT-NMR spectra of electronically different substituted derivatives showing that the electronic substituent effect on the aryl group does not affect the height of the rotational barrier. This indicates that the substituents are essentially oriented orthogonally to the plane of the β-pyrrolidino enoates.
PYRAZOLE DERIVATIVES AS GAMMA-SECRETASE INHIBITORS USEFUL IN THE TREATMENT OF ALZHEIMER’S DISEASE
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Page 34; 35, (2010/02/09)
The compounds of formula (I): inhibit gamma-secretase and hence are of utility in the treatment or prevention of Alzheimer's disease.
Regioselective rapid analogue syntheses of 1-methyl-3,5-diarylpyrazoles via palladium-catalysed coupling to 3(5)-pyrazolyl nonaflates
Bourrain, Sylvie,Ridgill, Mark,Collins, Ian
, p. 795 - 798 (2007/10/03)
Regioselective rapid analogue syntheses of 1-methyl-3,5-diarylpyrazoles were developed, based on Pd-catalysed couplings to 1-methyl-3(5)-arylpyrazole nonaflates, which offered an advantage in hydrolytic stability over the corresponding triflates. The new bifunctional reagent 1-methyl-3-bromo-pyrazol- 5-yl nonaflate underwent highly chemoselective Pd-catalysed couplings to the nonaflate, followed by Suzuki couplings to the bromide, allowing sequential, regioselective introduction of the two aryl substituents.