A Simple Synthesis of Polyfunctionalized 4-Aminopyrazolidin-3-ones as ‘Aza-deoxa’ Analogs of<scp>D</scp>-Cycloserine
作者:Ana Novak、Matej Štefanič、Uroš Grošelj、Martina Hrast、Marta Kasunič、Stanislav Gobec、Branko Stanovnik、Jurij Svete
DOI:10.1002/hlca.201300169
日期:2014.2
A simple five‐step synthesis of fully substituted (4RS,5RS)‐4‐aminopyrazolidin‐3‐ones as analogs of D‐cycloserine was developed. It comprises a two‐step preparation of 5‐substituted (4RS,5RS)‐4‐(benzyloxycarbonylamino)pyrazolidin‐3‐ones, reductive alkylation at N(1), alkylation of the amidic N(2) with alkyl halides, and simultaneous hydrogenolytic deprotection/reductive alkylation of the primary NH2
Various N-benzyloxycarbonyl-α-dehydroamino acid methyl esters were newly synthesized by the condensation of α-oxocarboxylic acids with benzyl carbomate followed by methyl esterfication. Others were obtained by the Wittig-Horner reaction of aldehydes with diethoxyphosphinylglycine and by the base-catalyzed β-elimination of β-acetoxy or β-halo-α-amino acids.
The rearrangement of (E)-didehydroamino acid derivatives to the corresponding Z-derivatives under acid or basic catalysis as well as under the influence of radicals has been investigated. The condensation of N-benzyloxycarbonyl or N-tert-butoxycarbonyl protected alkyl 2-amino-2-(dimethoxyphosphoryl)acetates with aldehydes or ketones in dichloromethane in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene furnishes (Z)-didehydroamino acid ester derivatives diastereoselectively in excellent yields and with high purity.
研究了在酸或碱催化以及自由基影响下,(E)-二脱氢氨基酸衍生物重排为相应的 Z 衍生物的过程。在 1,8- 二氮杂双环[5.4.0]十一碳-7-烯存在下,N-苄氧羰基或 N-叔丁氧羰基保护的 2-氨基-2-(二甲氧基磷酰)乙酸烷基酯与醛或酮在二氯甲烷中缩合,可产生非对映选择性的 (Z)-二脱氢氨基酸酯衍生物,收率极高,纯度也很高。
Effenberger, Franz; Kuehlwein, Juergen; Baumgartner, Christian, Liebigs Annalen der Chemie, 1994, # 11, p. 1069 - 1074
作者:Effenberger, Franz、Kuehlwein, Juergen、Baumgartner, Christian
DOI:——
日期:——
Effenberger, Franz; Kuehlwein, Juergen; Drauz, Karlheinz, Liebigs Annalen der Chemie, 1993, # 12, p. 1295 - 1302