19006-63-4Relevant articles and documents
Mild and Regioselective N-Alkylation of 2-Pyridones in Water
Hao, Xin,Xu, Zhongmiao,Lu, Hongfu,Dai, Xuedong,Yang, Ting,Lin, Xichen,Ren, Feng
supporting information, p. 3382 - 3385 (2015/07/28)
A mild and regioselective N-alkylation reaction of 2-pyridones in water has been developed. Tween 20 (2% w/w) was added to create a micellar system for improved solubility of starting materials, which leads to enhanced reaction rates. The protocol demonstrated a wide substrate scope with good isolated yields (40-94%) for all of the 24 examples evaluated. High regioselectivity favoring N-alkylation over O-alkylation was observed for benzyl halides (>5:1), primary alkyl halides (>6:1), and bulky and less reactive secondary alkyl halides (>2.4:1).
Homosecoiridoid alkaloids with amino acid units from the flower buds of lonicera japonica
Yu, Yang,Zhu, Chenggen,Wang, Sujuan,Song, Weixia,Yang, Yongchun,Shi, Jiangong
, p. 2226 - 2233 (2014/01/17)
Nine new homosecoiridoid alkaloids, named lonijaposides O-W (1-9), along with 19 known compounds, were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their structures and absolute configurations were determined by spectroscopic data analysis and chemical methods. Lonijaposides O-W have structural features that involve amino acid units sharing the N atom with a pyridinium (1-5) or nicotinic acid (6-9) moiety. The absolute configurations of the amino acid units were determined by oxidation of each pyridinium ring moiety with potassium ferricyanide, hydrolysis of the oxidation product, and Marfey's analysis of the hydrolysate. This procedure was validated by oxidizing and hydrolyzing synthetic model compounds. The phenylalanine units in compounds 4, 5, and 9 have the d-configuration, and the other amino acid units in 1-3 and 6-8 possess the l-configuration. Compounds 1, 4, 6, and 9 and the known compounds 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 5′-O-methyladenosine exhibited antiviral activity against the influenza virus A/Hanfang/359/95 (H3N2) with IC50 values of 3.4-11.6 μM, and 4 inhibited Coxsackie virus B3 replication with an IC50 value of 12.3 μM.
Value of zeolites in asymmetric induction during photocyclization of pyridones, cyclohexadienones and naphthalenones
Sivasubramanian, Karthikeyan,Kaanumalle, Lakshmi S.,Uppili, Sundararajan,Ramamurthy
, p. 1569 - 1576 (2008/02/05)
Two strategies, namely chiral inductor and chiral auxiliary approaches, have been examined within zeolites with the aim of achieving asymmetric induction during the photocyclization of cyclohexadienone, naphthalenone and pyridone derivatives. Within zeoli