Amine-catalyzed synthesis of N2-sulfonyl 1,2,3-triazole in water and the tunable N2-H 1,2,3-triazole synthesis in DMSO via metal-free enamine annulation
作者:Yanhui Guo、Yunyun Liu、Jie-Ping Wan
DOI:10.1016/j.cclet.2021.08.003
日期:2022.2
N2-H 1,2,3-triazoles via organocatalytic annulation of enaminone/enaminoester with sulfonylazide has been realized. The unconventional selectivity providing N2-sulfoyl 1,2,3-triazoles takes place in pure water, wherein the hydrogen bond effect between water and the intermediate resulting from enamine-azide corporation accounts for the novel reaction selectivity. On the other hand, the reactions conducted
synthetic usefulness of obtained 4-nitrobuta-1,3-dien-1-amines has also been demonstrated by achieving the synthesis of multisubstituted 5-nitro-1,6-dihydropyridines in two-component cyclocondensation reactions of 4-nitrobuta-1,3-dien-1-amines with aromatic or aliphatic aldehydes. Lastly, diverse N-H and N-substituted 5-nitro-1,6-dihydropyridines have been obtained in 35–87% yields.
[EN] PYRIDINE COMPOUNDS AS INHIBITORS OF DIPEPTIDYL PEPTIDASE IV<br/>[FR] COMPOSES PYRIDINES UTILISES COMME INHIBITEURS DE DIPEPTIDYLE PEPTIDASE IV
申请人:TAKEDA PHARMACEUTICAL
公开号:WO2005042488A1
公开(公告)日:2005-05-12
A compound represented by the formula wherein R1 and R2 are the same or different and each is an optionally substituted hydrocarbon group or an optionally substituted hydroxy group; R3 is an optionally substituted aromatic group; R4 is an optionally substituted amino group; L is a divalent chain hydrocarbon group; Q is a bond or a divalent chain hydrocarbon group; and X is a hydrogen atom, a cyano group, a nitro group, an acyl group, a substituted hydroxy group, an optionally substituted thiol group, an optionally substituted amino group or an optionally substituted cyclic group; provided that when X is an ethoxycarbonyl group, then Q is a divalent chain hydrocarbon group. The compound has a peptidase inhibitory action, is useful as an agent for the prophylaxis or treatment of diabetes and the like, and is superior in efficacy, duration of action, specificity, lower toxicity and the like.
Isothiourea and Brønsted Acid Cooperative Catalysis: Enantioselective Construction of Dihydropyridinones
作者:Yu-Chen Zhang、Rui-Long Geng、Jin Song、Liu-Zhu Gong
DOI:10.1021/acs.orglett.0c00461
日期:2020.3.20
Asymmetric annulation of bench-stable α,β-unsaturated aryl esters with enamines was realized via cooperative catalysis of chiral isothiourea and Brønsted acid. This reaction proceeds via a chiral α,β-unsaturatedacyl ammonium intermediate and offers a rapid access to functionalized 3,4-dihydropyridin-2-ones in high yields and excellent enantioselectivities.
Divergent Synthesis of Multisubstituted Unsymmetric Pyrroles and Pyrrolin-4-ones from Enamino Esters via Copper-Catalyzed Aerobic Dimerization
作者:Zhi-Wei Chen、Lei Zheng、Jin Liu
DOI:10.1002/ejoc.201900341
日期:2019.5.26
An efficient strategy for copper‐catalyzed synthesis of multisubstituted unsymmetric pyrroles and pyrrolin‐4‐ones, under oxygen atmosphere, from enamino esters through oxidative cyclization and 1,2‐aryl migration was developed. The additive plays a crucial role in this divergent transformation, and these transformations have different mechanisms (radical and non‐radical).