138715-51-2Relevant articles and documents
Enantioselective Synthesis of Pyroglutamic Acid Esters from Glycinate via Carbonyl Catalysis
Ma, Jiguo,Zhou, Qinghai,Song, Guanshui,Song, Yongchang,Zhao, Guoqing,Ding, Kuiling,Zhao, Baoguo
supporting information, p. 10588 - 10592 (2021/04/06)
Direct α-functionalization of NH2-free glycinates with relatively weak electrophiles such as α,β-unsaturated esters still remains a big challenge in organic synthesis. With chiral pyridoxal 5 d as a carbonyl catalyst, direct asymmetric conjugated addition at the α-C of glycinate 1 a with α,β-unsaturated esters 2 has been successfully realized, to produce various chiral pyroglutamic acid esters 4 in 14–96 % yields with 81–97 % ee's after in situ lactamization. The trans and cis diastereomers can be obtained at the same time by chromatography and both of them can be easily converted into chiral 4-substituted pyrrolidin-2-ones such as Alzheimer's drug Rolipram (11) with the same absolute configuration via tert-butyl group removal and subsequent Barton decarboxylation.
Synthesis of the novel antidepressant (R)-(-)-Rolipram
Langlois, Nicole,Wang, Hai-Shan
, p. 3133 - 3144 (2007/10/03)
Enantioselective synthesis of (R)-Rolipram 1 has been achieved through a conjugate addition of cyanide to enantiomerically pure 2-(2-aryl ethenyl)oxazoline 2, followed by selective reduction of the adduct with NaBH4-NiCl2.
Trisubstituted phenyl analogs having activity for congestive heart failure
-
, (2008/06/13)
Novel trisubstituted phenyl analogs are now found to have activity as for the treatment of congestive heart failure.
