Reaction of methyl N-Boc-N-phenoxycarbonylglycinate with various aldehydes afforded the corresponding cis-4,5-oxazolidinone derivatives, which were effectively converted to (E)-α,β-didehydroamino acids by means of a base. Furthermore, N-deprotection of the oxazolidinone derivatives and subsequent coupling reaction with Boc-amino acid furnished the corresponding dipeptides, which were transformed to dipeptide containing α,β-didehydroamino acid with high E selectivity.
Synthesis of Enantiomerically Pure Isoxazolidine Monomers for the Preparation of<i>β</i><sup>3</sup>-Oligopeptides by Iterative<i>α</i>-Keto AcidHydroxylamine (KAHA) Ligations
作者:Ying-Ling Chiang、Justin A. Russak、Nancy Carrillo、Jeffrey W. Bode
DOI:10.1002/hlca.201200484
日期:2012.12
for the synthesis of enantiomerically pure isoxazolidine monomers for the synthesis of β3‐oligopeptides via α‐keto acidhydroxylamine (KAHA) ligation is presented. This one‐pot synthetic method utilizes in situ generated nitrones bearing gulose‐derived chiral auxiliaries for the asymmetric 1,3‐dipolar cycloaddition with methyl 2‐methoxyacrylate. The resulting enantiomerically pure isoxazolidine monomers
[EN] PYRROLOPYRROLONE DERIVATIVES AS INHIBITORS OF NEUTROPHIL ELASTASE<br/>[FR] DERIVES DU PYRROLOPYRROLONE UTILISES COMME INHIBITEURS DE L'ELASTASE DE NEUTROPHILES
申请人:GLAXO GROUP LIMITED
公开号:WO1997036903A1
公开(公告)日:1997-10-09
(EN) There are described according to the invention compounds of formula (I) (relative stereochemistry indicated), wherein R1, R2, R3 and X are as defined in the specification, together with processes for preparing them, compositions containing them and their use as pharmaceuticals. Compounds of formula (I) are indicated $i(inter alia) for the treatment of chronic bronchitis.(FR) L'invention concerne des composés selon la formule (I) (stéréochimie relative indiquée). Dans la formule, R1, R2, R3 et X sont comme définis dans le descriptif. L'invention traite également de procédés pour préparer ces composés, de compositions les contenant et de leur utilisation comme produits pharmaceutiques. Les composés de la formule (I) sont indiqués, entre autres, pour le traitement de la bronchite chronique.
Dihydroxylation of Vinyl Sulfones: Stereoselective Synthesis of (+)- and (−)-Febrifugine and Halofuginone
作者:Noel P. McLaughlin、Paul Evans
DOI:10.1021/jo902396m
日期:2010.1.15
The asymmetric dihydroxylation of amino-functionalized vinyl sulfone 19 has been used for the 3-step preparation of 3-hydroxylpiperidine 24 in 86% enantiomeric excess. This enantiomerically enriched building block was used then to synthesize the naturally Occurring antimalarial alkaloid febrifugine 1 and its antiangiogenic analogue, halofuginone 3.