4835-96-5Relevant articles and documents
-
Farmer,R.F.,Hamer,J.
, p. 2418 - 2419 (1966)
-
-
Marvel,Frank
, p. 1675,1677 (1942)
-
Stereoselective synthesis of novel C-3 functionalized 3-sulfonyl-β-lactams: Promising biologically active heterocyclic scaffolds
Bhalla, Aman,Modi, Garima,Bari, Shamsher S.,Kumari, Anu,Berry, Shiwani,Hundal, Geeta
, p. 1160 - 1165 (2017)
An efficient and operationally simple strategy for the stereoselective synthesis of novel C-3 functionalized 3-sulfonyl-β-lactam heterocycles is described. The C-3 functionalized 3-phenyl/benzylsulfonyl-β-lactams 3/3′, 5/5′ has been synthesized via Michael addition using different Michael acceptors on trans-3-phenyl/benzylsulfonyl-β-lactams 2(a–f) using K2CO3as a base and acetonitrile/DMF as solvents. The reaction furnished exclusively cis-β-lactam adducts 3(a–r) using sterically less hindered Michael acceptors. Further, the effect of steric bulk and chiralilty of Michael acceptors was explored to achieve target C-3 functionalized β-lactams 3(s-u)/3′(s-u) and 5(a–c)/5′(a–c). The structural and stereochemical analysis of novel β-lactams were carried out using FT-IR, NMR (1H,13C,1H-1H COSY,1H-13C COSY and13C DEPT-135), elemental analysis (CHNS), mass spectrometry (EIMS and LCMS) in representative cases and single crystal X-ray crystallographic studies (3e). The cis or trans configuration of the Michael acceptor (E) at C-3 was assigned with respect to C4-H.
Visible-Light-Induced Trifluoromethylation of Allylic Alcohols
Li, Bowen,Zeng, Wubing,Wang, Lin,Geng, Zhishuai,Loh, Teck-Peng,Xie, Peizhong
supporting information, p. 5235 - 5240 (2021/07/20)
An organic photoredox-catalyzed dehydroxylative trifluoromethylation of allylic alcohols was developed in an environmentally benign manner. In this reaction, the readily available CF3SO2Na was selected as the trifluoromethylation reagent. The in situ generated byproduct SO2 was reutilized to activate C-OH bond, which enabled this dehydroxylative trifluoromethylation to be performed conveniently. A variety of multifunctionalized CF3-allylic compounds were obtained in high yields and excellent stereoselectivity.
Late-Stage Macrocyclization of Bioactive Peptides with Internal Oxazole Motifs via Palladium-Catalyzed C-H Olefination
Liu, Shu,Cai, Chuangxu,Bai, Zengbing,Sheng, Wangjian,Tan, Jiantao,Wang, Huan
supporting information, p. 2933 - 2937 (2021/05/04)
Oxazole is an important pharmacophore and exists in the backbone of many bioactive peptide natural products and peptidomimetics. Efficient methods for the synthesis and direct functionalization of complex oxazole-containing peptides are in high demand. Herein, we report the late-stage site-selective functionalization of oxazole-containing peptides via palladium-catalyzed δ-C(sp2)-H olefination of phenylalanine, tryptophan, and tyrosine residues. This strategy utilizes oxazole motifs as internal directing groups and provides access to oxazole-containing peptide macrocycles with bioactivities.