N-Halosuccinimide/SiCl4 as general, mild and efficient systems for the α-monohalogenation of carbonyl compounds and for benzylic halogenation
作者:Tarek A. Salama、Zoltán Novák
DOI:10.1016/j.tetlet.2011.05.135
日期:2011.8
Combinations of N-halosuccinimide and tetrachlorosilane in acetonitrile were found to be efficient systems for the selective α-monohalogenation of carbonyl compounds as well as for benzylichalogenation under mild conditions.
Highly Enantioselective Synthesis of Fused Tri‐ and Tetrasubstituted Aziridines: aza‐Darzens Reaction of Cyclic Imines with α‐Halogenated Ketones Catalyzed by Bifunctional Phosphonium Salt
作者:Jianke Pan、Jia‐Hong Wu、Hongkui Zhang、Xiaoyu Ren、Jian‐Ping Tan、Lixiang Zhu、Hong‐Su Zhang、Chunhui Jiang、Tianli Wang
DOI:10.1002/anie.201900613
日期:2019.5.27
The first enantioselective aza‐Darzens reaction of cyclic imines with α‐halogenated ketones was realized under mild reaction conditions by using amino‐acid‐derived bifunctional phosphonium salts as phase‐transfer promoters. A variety of structurally dense tri‐ and tetrasubstituted aziridine derivatives, containing benzofused heterocycles as well as spiro‐structures, were readily synthesized in high yields
Dipeptide-Based Phosphonium Salt Catalysis: Application to Enantioselective Synthesis of Fused Tri- and Tetrasubstituted Aziridines
作者:Jia-Hong Wu、Jianke Pan、Tianli Wang
DOI:10.1055/s-0039-1690192
日期:2019.12
salt catalysis. This article briefly discusses the recent development in asymmetricreactions (mainly including nucleophilic additions and cyclizations) promoted by chiral quaternary phosphonium salt catalysts. We expect that more catalyticasymmetricreactions will be developed on the basis of such new phase-transfer catalytic systems in the near future.
Discovery and SAR of potent, orally available and brain-penetrable 5,6-dihydro-4H-3-thia-1-aza-benzo[e]azulen- and 4,5-dihydro-6-oxa-3-thia-1-aza-benzo[e]azulen derivatives as neuropeptide Y Y5 receptor antagonists
from a potent Y5 antagonist (2) with thiazole fragments that exhibit weak Y5 affinities followed by lead optimisation led to the discovery of (5,6-dihydro-4H-3-thia-1-aza-benzo[e]azulen-2-yl)-piperidin-4-ylmethyl-amino and (4,5-dihydro-6-oxa-3-thia-1-aza-benzo[e]azulen-2-yl)-piperidin-4-ylmethyl-amino derivatives. Both classes of compounds are capable of delivering potent and selectiveorally and centrally
Stereochemical considerations and the antiinflammatory activity of 6-amino-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-ols and related derivatives
作者:Shing Chun Wong、Sandra Sasso、Howard Jones、James J. Kaminski
DOI:10.1021/jm00367a005
日期:1984.1
significant antiinflammatoryactivity. The antiinflammatoryactivity of the amino alcohols was also significantly influenced by the position and nature of the aromatic substituent. Latentiation of the amino alcohol function resulted in analogues exhibiting antiinflammatoryactivity equivalent to their amino alcohol precursors. Masking the amino alcohol function as a more stable derivative led to analogues