56850-57-8Relevant academic research and scientific papers
New Strategy for Forging Contiguous Quaternary Carbon Centers via H 2 O 2 -Mediated Ring Contraction
Hu, Jiadong,Yu, Xin,Xie, Weiqing
, p. 2517 - 2524 (2017/09/28)
Stereospecific construction of contiguous quaternary carbon centers constitutes a major challenge in natural product synthesis. A general protocol that enables stereospecific construction of all stereoisomers of such a moiety remains elusive. In this article, we will discuss the oxidative ring contraction of all-substituted cyclic α-formyl ketones mediated by H 2 O 2, which provides a facile access to the stereospecific construction of contiguous quaternary carbon centers.
Oxidative rearrangement of malondialdehyde: Substrate scope and mechanistic insights
Yu, Xin,Liu, Zheng,Xia, Zilei,Shen, Zhigao,Pan, Xixian,Zhang, Hui,Xie, Weiqing
, p. 53397 - 53401 (2015/01/16)
A novel oxidative rearrangement of malondialdehyde was described. Under the effect of H2O2, malondialdehyde smoothly transferred to carboxylic acid with C-C bond cleavage in good to excellent yields. Mechanistic studies showed that this reaction proceeded via the formation of a 1,2-dioxolane intermediate, followed by concert C-C, O-O, C-H bond cleavage and a hydride shift.
β N-O turns and helices induced by β2-aminoxy peptides: Synthesis and conformational studies
Jiao, Zhi-Gang,Chang, Xiao-Wei,Ding, Wei,Liu, Guo-Jun,Song, Ke-Sheng,Zhu, Nian-Yong,Zhang, Dan-Wei,Yang, Dan
supporting information; experimental part, p. 1791 - 1799 (2012/02/02)
Herein, we report an efficient route for the asymmetric synthesis of β2-aminoxy acids as well as experimental and theoretical studies of conformations of peptides composed of β2-aminoxy acids. The nine-membered-ring intramolecular hydrogen bonds, namely, β N-O turns, are generated between adjacent residues in those peptides, in accordance with our computational results. The presence of two consecutive homochiral β N-O turns leads to the formation of β N-O helical structures in solution, although both helical (composed of two β N-O turns of the same handedness) and reverse-turn (composed of two β N-O turns with opposite handedness) structures are of similar stability, as suggested by theoretical studies. Nevertheless, two slightly different conformations, with the same handedness, of β2-aminoxy monomers have been observed in the solid state and in solution according to our X-ray and 2D NOESY studies.
3(1-hydoxyethyl)azetidinone compounds and their production
-
, (2008/06/13)
An amino acid compound of the formula: STR1 wherein R is a lower alkyl group, R1 is a hydrogen atom or a protecting group for carboxyl, R2 is a hydrogen atom, a protecting group for amino, an optionally substituted allyl group of the formula: STR2 (wherein R3 and R4 are each a hydrogen atom, a lower alkyl group or an aryl group), a beta-hydroxyethyl group in which the hydroxyl group is optionally protected, a formylmethyl group in which the formyl group is optionally protected, a carboxymethyl group in which the carboxyl group is protected or a 2-furylmethyl group and X is an optionally protected carboxyl group, a hydroxymethyl group in which the hydroxyl group is optionally protected or a substituted mercaptomethyl group of the formula: (wherein R5 is an aryl group or an ar(lower)alkyl group), which is a useful intermediate in the synthesis of 1-alkylcarbapenem compounds.
