168297-85-6Relevant articles and documents
Stereoselective Alkylation of Chiral Titanium(IV) Enolates with tert-Butyl Peresters
Pérez-Palau, Marina,Sanosa, Nil,Romea, Pedro,Urpí, Fèlix,López, Rosa,Gómez-Bengoa, Enrique,Font-Bardia, Mercè
supporting information, p. 8852 - 8856 (2021/11/17)
Here, we present a new stereoselective alkylation of titanium(IV) enolates of chiral N-acyl oxazolidinones with tert-butyl peresters from Cα-branched aliphatic carboxylic acids, which proceeds through the decarboxylation of the peresters and the subsequent formation of alkyl radicals to produce the alkylated adducts with an excellent diastereoselectivity. Theoretical calculations account for the observed reactivity and the outstanding stereocontrol. Importantly, the resultant compounds can be easily converted into ligands for asymmetric and catalytic transformations.
Asymmetric Total Synthesis and Evaluation of Antitumor Activity of Ophiorrhisine A and Its Derivatives
Onozawa, Tadayoshi,Kitajima, Mariko,Kogure, Noriyuki,Takayama, Hiromitsu
, p. 15312 - 15322 (2019/01/03)
The first asymmetric total synthesis of ophiorrhisine A (1), a new cyclic tetrapeptide isolated from Ophiorrhiza nutans, was accomplished via an intramolecular aromatic nucleophilic substitution reaction (IMSNAr) of a linear tripeptide to construct a 14-membered paracyclophane ring, resulting in confirmation of its structure and absolute configuration. The structure-activity relationship study of 1 and its derivatives demonstrated that some derivatives possessed cytotoxicity toward human cancer cell lines A549, HT29, and HCT116.
Asymmetric radical addition of TEMPO to titanium enolates
Mabe, Phillip J.,Zakarian, Armen
supporting information, p. 516 - 519 (2014/04/03)
A mild method for a-hydroxylation of N-acyl oxazolidinones by asymmetric radical addition of the 2,2,6,6-tetramethylpiperidine N-oxy (TEMPO) radical to titanium enolates was developed. The high diastereoselectivity and broad scope of the reaction show synthetic utility for the a-hydroxylation of substrates that are not tolerant to strongly basic conditions.