Solid-phase synthesis of N , N ′-substituted acylguanidines
作者:Dharmpal S Dodd、Yufen Zhao
DOI:10.1016/s0040-4039(00)02265-6
日期:2001.2
An efficient method for the solid-phase synthesis of N,N′-substituted acylguanidines is presented. The key-step involves the N-acylation of resin immobilized S-methylisothiourea with a variety of carboxylic acids using PyAOP as the coupling agent. The resulting resin bound N-acyl-derivatives are reacted with a host of amines and the N-acyl,N′-alkyl(aryl)guanidines liberated from the resin upon exposure
Facile synthesis of 3-amino-5-aryl-1,2,4-oxadiazoles via PIDA-mediated intramolecular oxidative cyclization
作者:Kuan Lu、Liancheng Duan、Boxuan Xu、Weile Yin、Di Wu、Yanfang Zhao、Ping Gong
DOI:10.1039/c6ra08871f
日期:——
A mild and efficient method for the synthesis of 3-amino-5-aryl-1,2,4-oxadiazole by intramolecularcyclization using PhI(OAc)2 (PIDA) as an oxidant is developed. Various 3-amino-5-aryl-1,2,4-oxadiazoles are prepared in moderate to good yields, and the PIDA-mediated N–O bond formation mechanism is suggested. In view of the readily available starting materials, operational simplicity, high functionality
An eco-friendly protocol for synthesis of thiourea derivatives: 1-benzoyl-3-benzylguanidine and 1-benzoyl-3-benzyl-O-ethylisourea. A possible non-purely thermal microwave assisted reaction
作者:Heiddy Marquez、André Loupy、Osmar Calderon、Eduardo R. Pérez
DOI:10.1016/j.tet.2005.12.037
日期:2006.3
nucleophilic amines promoted the sulfur elimination by attack on the thiocarbonyl group in both thiourea and thiocarbamates to afford guanidines and isourea, respectively. Transesterification products were obtained from p-TsOH catalyzed reaction of thiocarbamate with alcohols under MW-solvent-free conditions. Very important non-purely thermal MW specific effects were evidenced and attributed to stabilization
使用KF在干燥介质条件下从1-苯甲酰基-3-苄基硫脲和苯甲酰基-乙基硫代氨基甲酸酯以良好的收率(分别为68%和76%)合成了1-苯甲酰基-3-苄基胍和1-苯甲酰基-3-苄基-O-乙基异脲–微波辐射下的Al 2 O 3。强亲核胺通过攻击硫脲和硫代氨基甲酸酯中的硫代羰基而促进了硫的消除,从而分别提供了胍和异脲。酯交换产物是在无MW溶剂的条件下,由对氨基甲酸酯与硫醇的对-TsOH催化反应制得的。证明了非常重要的非纯热MW特有效应,并归因于物质与波浪之间的库仑相互作用而稳定。
A simple one-pot methodology for the synthesis of substituted benzoylguanidines from benzoylthioureas using tert-butyl hydroperoxide
作者:Henrique Esteves、Ângelo de Fátima、Rosane de P. Castro、José R. Sabino、Fernando Macedo、Tiago Oliveira Brito
DOI:10.1016/j.tetlet.2015.10.088
日期:2015.12
The potential of tert-butyl hydroperoxide as a reagent in the guanylation of benzoylthioureas in the presence of amines has been evaluated in a systematic study involving substrates bearing N-2-substituents with different electronic properties. The results show that (BuOOH)-Bu-t is a suitable and robust reagent for the synthesis of either N-1,N-2,N-3-tri- and tetrasubstituted or N-1,N-2-disubstituted guanidines from N-2-substituted N-1-benzoylthioureas and N-1-benzoylthioureas, respectively. The recrystallised guanylation adducts were readily obtained in good yields and at high purity levels after a simple one-pot reaction procedure. The crystal structures of two novel benzoylguanidines are provided. (C) 2015 Elsevier Ltd. All rights reserved.