An eco-friendly synthesis and antimicrobial activities of dihydro-2H-benzo- and naphtho-1,3-oxazine derivatives
作者:Bijoy P. Mathew、Awanit Kumar、Satyasheel Sharma、P.K. Shukla、Mahendra Nath
DOI:10.1016/j.ejmech.2009.12.058
日期:2010.4
3]oxazin-3(4H)-yl)ethane derivatives was obtained through an eco-friendly Mannich type condensation–cyclization reaction of phenols or naphthols with formaldehyde and primary amines in water at ambient temperature. Preliminary in vitro antimicrobialactivity of the synthesized compounds was assessed against six pathogenic fungi, two Gram-negative and two Gram-positive bacteria. Some of the screened compounds
One pot synthesis of [1,3]-oxazine and [1,3]-thiazine derivatives under thermal and microwave conditions
作者:S. Tumtin、I. T. Phucho、A. Nongpiur、R. Nongrum、J. N. Vishwakarma、B. Myrboh、R. L. Nongkhlaw
DOI:10.1002/jhet.280
日期:——
efficient synthesis of substituted benzo [1,3] oxazine and benzo [1,3] thiazine derivativesunder conventional heating, as well as microwave irradiation is reported. The compounds were obtained by the reaction of electron rich phenols, formaldehyde, and aromatic amines in methanol. Reactions which take 12–16 hr under conventional heating were successfully completed within a few minutes undermicrowave irradiation
Mixtures of different benzoxazine resins and elemental sulfur (S8) are prepared and then reacted at 120 °C, below the temperature for radical formation of sulfur. The progress of the reaction and the chemical structures of the main products are monitored and characterized by proton nuclear magnetic resonance spectroscopy (1H NMR) and Fourier transform infrared spectroscopy (FT-IR). Thermal analysis
制备了不同的苯并恶嗪树脂和元素硫(S 8)的混合物,然后在低于该温度的120°C下反应生成硫自由基。通过质子核磁共振波谱(1 H NMR)和傅立叶变换红外光谱法(FT-IR)对反应进程和主要产物的化学结构进行监测和表征。还通过差示扫描量热法(DSC)对所有反应系统进行热分析。在苯并恶嗪中引入S 8会在反应体系中产生一个带有席夫碱和酚式-OH的新结构,当低至5 mol%时,它会引发聚合温度降低约15%。添加S 8。