A series of novel 3-/2,3-substituted pyrido[4,3-e][1,2,4]triazino[3,2-c][1,2,4]thiadiazine 6,6-dioxides 4-28 have been synthesized by the reaction of 3-amino-2-(4-thioxo-1,4-dihydropyridin-3-yl-sulfonyl)guanidine with either 2-oxoalkanoic acids and its esters, or phenylglyoxylic hydrates in glacial acetic acid. Some of them exhibited reasonable or moderate anticancer activity toward human cancer cell
A convenient enantioselective decarboxylative aldol reaction to access chiral α-hydroxy esters using β-keto acids
作者:Zhiqiang Duan、Jianlin Han、Ping Qian、Zirui Zhang、Yi Wang、Yi Pan
DOI:10.3762/bjoc.10.95
日期:——
We show a convenient decarboxylative aldol process using a scandium catalyst and a PYBOX ligand to generate a series of highly functionalized chiral alpha-hydroxy esters. The protocol tolerates a broad range of beta-keto acids with inactivated aromatic and aliphatic alpha-keto esters. The possible mechanism is rationalized.
Modular Synthesis of α,α-Diaryl α-Amino Esters via Bi(V)-Mediated Arylation/S<sub>N</sub>2-Displacement of Kukhtin–Ramirez Intermediates
作者:Alessio Calcatelli、Ross M. Denton、Liam T. Ball
DOI:10.1021/acs.orglett.2c03201
日期:2022.11.4
We report a concise and modular approach to α,α-diaryl α-amino esters from readily available α-keto esters. This mild, one-pot protocol proceeds via ketone umpolung, with in situ formation of a Kukhtin–Ramirez intermediate preceding sequential electrophilic arylation by Bi(V) and SN2 displacement by an amine. The methodology is compatible with a wide range of anilines and primary amines - including