Syntheses of β-lactams from acetic acids and imines induced by phenyl dichlorophosphate reagent
作者:Ana Arrieta、Fernando P. Cossio、Claudio Palomo
DOI:10.1016/s0040-4020(01)96484-1
日期:——
Among the reagents known to produce β-lactams from imines and acetic acids, only phenyl dichlorophosphate and 1-methyl-2-chloropyridinium iodide are suitable for the synthesis of vinylamino- β-lactams. Reaction of acetic acids with ethanolimine derivatives promoted by phenyl dichlorophosphate affords oxazolidines instead β-lactams. Protection of the hydroxyl group as the trimethylsilyl ether in the
N,N-Dimethylphosphoramidic dichloride: a convenient reagent for the preparation of β-lactams from acetic acids and imines
作者:Fernando P Cossío、Iñaki Ganboa、Jesús M García、Begoña Lecea、C Palomo
DOI:10.1016/s0040-4039(00)96016-7
日期:1987.1
A convenient reagent for the preparation of β-lactams from aceticacids and imines is described. A new route to α-keto-β-lactams from 3-bis(ethylthio)β-lactams is also reported. Reaction of 4-acethyl-β-lactams with diazomethane is also made.
A convenient synthetic approach to alpha-amino-beta-lactam synthesis promoted by phenyl dichlorophosphate reagent
作者:Jesus M. Aizpurua、Inlaki Ganboa、Fernando P. Cossío、Alberto Gonzalez、Ana Arrieta、Claudio Palomo
DOI:10.1016/s0040-4039(01)91200-6
日期:1984.1
beta-lactam synthesis, is shown to be very efficient for the synthesis of alpha-vinylamino-beta-lactams from Dane salts and Schiffbases. Someobservations toward the scope of the method are also briefly described. The interaction of acetic acids with ethanolimines afforded beta-lactams and/or oxazolidines according to the synthetic methodology used.
Durch Umsetzung des Dane‐Salzes mit fünf‐bzw. sechsgliedrigen Iminen entstehen Carbapename bzw. Carbacephamemit Vinylaminoseitenkette. Anhand von NOE‐Experimenten und einer Kristallstrukturanalyse wird die Z‐Konfiguration für die Substituenten am Brückenkopf und an C–6 des Adduktes 4a gesichert. Nach Abspaltung der Schutzgruppe werden die zugehörigen Amino‐ bzw. Bromverbindungen zugänglich.
通过将丹麦盐与五或 六元亚胺产生带有乙烯基氨基侧链的碳青霉烯类或碳青霉烯类。在 NOE 实验和晶体结构分析的基础上,确认了桥头和加合物 4a 的 C-6 处取代基的 Z 构型。保护基团被分离后,可以使用相关的氨基或溴化合物。
Stereoregulated synthesis of β-lactams from schiff bases derived from threonine esters
作者:Ajay K. Bose、Maghar S. Manhas、James M. van der Veen、Shamsher S. Bari、Dilip R. Wagle
DOI:10.1016/s0040-4020(01)81577-5
日期:1992.6
3-substituted-2-azetidinones has been prepared by the annelation of Schiff bases derivedfrom cinnamaldehyde and D-threonine esters and their absolute configuration determined. When the β-hydroxyl group of threonine is unprotected, both enantiomeric forms of N-unsubstituted 3,4-disubstituted-2-azetidinones can be prepared from a single β-lactam-forming reaction. On the other hand, by converting the hydroxyl