- Synthesis of L-4,4-difluoroglutamic acid via electrophilic difluorination of a lactam.
-
[formula: see text] An enantiomerically pure bicyclic lactam proved to be an excellent substrate for electrophilic difluorination using N-fluorobenzenesulfonimide. The resulting difluorinated lactam can be easily converted into L-4,4-difluoroglutamic acid. To the best of our knowledge, this is the first example of a synthetically useful electrophilic difluorination of an unactivated lactam.
- Konas,Coward
-
-
Read Online
- Bicyclic-Fused Heteroaryl or Aryl Compounds
-
Compounds, tautomers and pharmaceutically acceptable salts of the compounds are disclosed, wherein the compounds have the structure of Formula Ia, as defined in the specification. Corresponding pharmaceutical compositions, methods of treatment, methods of synthesis, and intermediates are also disclosed.
- -
-
Paragraph 0507; 0508; 0509
(2015/10/28)
-
- Synthesis, evaluation of anti-HIV-1 and anti-HCV activity of novel 2′,3′-dideoxy-2′,2′-difluoro-4′-azanucleosides
-
A series of 2′,3′-dideoxy-2′,2′-difluoro-4′- azanucleosides of both pyrimidine and purine nucleobases were synthesized in an efficient manner starting from commercially available L-pyroglutamic acid via glycosylation of difluorinated pyrrolidine derivative 15. Several 4′-azanucleosides were prepared as a separable mixture of α- and β-anomers. The 6-chloropurine analogue was obtained as a mixture of N 7 and N9 regioisomers and their structures were identified based on NOESY and HMBC spectral data. Among the 4′-azanucleosides tested as HIV-1 inhibitors in primary human lymphocytes, four compounds showed modest activity and the 5-fluorouracil analogue (18d) was found to be the most active compound (EC50 = 36.9 μM) in this series. None of the compounds synthesized in this study demonstrated anti-HCV activity.
- Martínez-Montero, Saúl,Fernández, Susana,Sanghvi, Yogesh S.,Theodorakis, Emmanuel A.,Detorio, Mervi A.,McBrayer, Tamara R.,Whitaker, Tony,Schinazi, Raymond F.,Gotor, Vicente,Ferrero, Miguel
-
p. 6885 - 6893
(2013/01/15)
-
- Reactivity Enhancement for Chiral Dirhodium(II) Tetrakis (Carboxamidates)
-
Difluorinated ligands from azetidinone-4-carboxylates and pyrrolidinone-5-carboxylate have been prepared, substituted onto dirhodium(II), and the reactivities and selectivities of the resulting catalysts have been examined. The fluorinated catalysts exhibit enhanced reactivity towards diazo decomposition but diminished enantioselectivities for cyclopropanation. Selectivity for ylide formation and rearrangement or Si-H insertion is enhanced or similar to that with unfluorinated analogues.
- Doyle, Michael P.,Hu, Wenhao,Phillips, Iain M.,Moody, Christopher J.,Pepper, Adrian G.,Slawin, Alexandra M. Z.
-
p. 112 - 117
(2007/10/03)
-