An efficient synthesis of new 2-aminomethyl-1,3,4-oxadiazoles from enantiomeric phenylglycine hydrazides
作者:Agnieszka Kudelko、Wojciech Zieliński
DOI:10.1016/j.tet.2008.11.096
日期:2009.2
New derivatives of 2-aminomethyl-1,3,4-oxadiazole were synthesized in the reactions of N-protected phenylglycine hydrazides and triethyl orthoesters (orthoformate, orthoacetate, orthopropionate, orthobenzoate) in the presence of glacial acetic acid. Studies on the cleavage reactions of the acid-sensitive N-BOC and N-Ac 1,3,4-oxadiazoles are presented. Spectral characteristics of the compounds and attempts
ABSTRACT N-substituted isomeric hydrazones of uridyl aldehyde have been synthesized. The occurrence of the dominant E isomers with respect to the azomethine group was confirmed by means of NMR spectroscopy. Synthesized hydrazones feature an acetonide moiety as a protection of two hydroxyl groups on the ribose part. The attempt to remove the protecting group resulted in an azo-hydrazone tautomeric mixture
摘要已合成了尿苷醛的 N-取代异构腙。通过NMR光谱证实存在关于偶氮甲碱基团的主要E异构体。合成的腙具有丙酮化物部分作为核糖部分上两个羟基的保护。去除保护基团的尝试产生了偶氮腙互变异构混合物。所述化合物可能是用于金属螯合的有价值的手性配体。对锰 (II) 离子对一种选定腙的亲和力进行了评估。
Facile one-pot synthesis of 2-amino-1,3,4-oxadiazole tethered peptidomimetics by molecular-iodine-mediated cyclodeselenization
作者:L. Santhosh、C. Srinivasulu、S. Durgamma、Girish Prabhu、Vommina V. Sureshbabu
DOI:10.1039/c7nj02278f
日期:——
Synthesis of 2-amino-1,3,4-oxadiazole tethered peptidomimetics through the reaction of Nα-protected amino acid hydrazides with isoselenocyanato esters in one- pot is described. The molecular-iodine-mediated cyclodeselenization of in situ generated selenosemicarbazide intermediates resulted in the facile formation of 2-amino-1,3,4-oxadiazoles under mild conditions in excellent yields. The method employs
The reaction of formaldehyde with enantiomerically pure α-N-protected amino acidhydrazides is described. The system has been investigated in different solvents, including both aqueous formaldehyde and paraformaldehyde, with the aim of simplifying the final reaction mixture. Aqueous formaldehyde in refluxing THF proved to be the best combination, affording mainly the corresponding monomeric N-methylene
A facile one-pot synthesis of Nα-Z/Boc-protected S-linked 1,3,4-oxadiazole tethered peptidomimetics
作者:Vommina V. Sureshbabu、B. Vasantha、G. Nagendra
DOI:10.1016/j.tetlet.2011.12.093
日期:2012.3
A new class of S-linked 1,3,4-oxadiazole-tethered N-alpha-protected peptidomimetics is designed and synthesized by a reaction of N-alpha-Z/Boc-protected 1,3,4-oxadiazole-2-thiol with alpha-bromo ester derived from amino acid. The protocol has also been employed for the synthesis of glycosylated amino acids and N,N'-orthogonally protected dipeptidomimetics bearing S-linked 1,3,4-oxadiazole mimetics as well. The intermediate 5-alkyl amino-1,3,4-oxadiazole-2-thiols have been isolated as stable compounds. Further, the chain extension at both N- and C-termini of N-protected S-linked 1,3,4-oxadiazole tethered dipeptidomimetics was also demonstrated. (C) 2012 Elsevier Ltd. All rights reserved.