An Efficient One‐Pot Four‐Component Synthesis of Some New Spirooxindole Dihydropyridine Using Alum as a Heterogeneous Green Catalyst

4‐Nitro‐2,3‐dihydrospiro[imidazo[1,2‐a ]indeno[2,1‐e ]pyridine‐5,3′‐indoline]‐2′,6(1H )‐dione derivatives have been synthesized in good yields in a one‐pot four‐component, and efficient process by reaction of corresponding isatins, 1,3‐indandione, diamine, and nitro ketene dithioacetal in the presence of KAl(SO₄)₂.12H₂O (Alum) as a nontoxic and easily available heterogeneous green catalyst.     

Alum： An efficient catalyst for one-pot synthesis of α-aminophosphonates

Alum (KAl(SO ₄) ₂·12H ₂O) is an inexpensive, efficient, non-toxic and mild catalyst for the one-pot synthesis of α-aminophosphonates.A three component reaction of an aldehyde/ketone, an amine and triethyl phosphite was carried out under solvent-free conditions to afford the corresponding a-aminophosphonates in short reaction times and high yields with the green aspects by avoiding toxic catalysts and solvents.     

明矾的宏观晶体形状

通过简易的热力学模型推测晶体宏观形状及缺陷的成因,借助于本科无机探究实验,培养明矾大晶体并测量其宏观参数,拟合出明矾的热力学参数,以解释明矾的宏观形状、缺陷并预测明矾的完美八面体的可能性与晶体的自范性。     

Design,Synthesis, and Antibacterial Evaluation of Some Novel 3′-(Phenylamino)-1′H-spiro[indoline-3,2′-quinazoline]-2,4′(3′H)-dione Derivatives

A combinatorial synthesis and evaluation of antibacterial activity against clinically isolated resistant strains of Gram-positive and Gram-negative bacteria of 3′-(phenylamino)-1′H-spiro[indoline-3,2′-quinazoline]-2,4′(3′H)-dione derivatives is described.     

Synthesis of Novel 1H‐Imidazol[1,2‐a]Indeno[2,1‐e]Pyridine‐6(5H)‐Ones Derivatives via a One‐Pot Four‐Component Condensation Reaction

1H‐imidazol[1,2‐a]indeno[2,1‐e]pyridine‐6(5H)‐ones derivatives were synthesized in a one‐pot four‐component condensation of corresponding aldehydes, 1,3‐indandione, diamine, and nitro ketene dithioacetal using KAl(SO₄)₂·12H₂O (alum) as nontoxic, reusable, inexpensive and easily available catalyst in good to excellent yields. This green protocol provides a powerful entry into fused polycyclic structures related to bioactive heterocycles.     

Alum (KAl(SO<Subscript>4</Subscript>)<Subscript>2</Subscript> · 12H<Subscript>2</Subscript>O) Catalyzed One-Pot Synthesis of Coumarins under Solvent-Free Conditions

Summary. Alum (KAl(SO₄)₂ · 12H₂O) is used as an efficient catalyst in the Pechmann condensation of phenol derivatives with β-keto esters leading to the formation of coumarins in excellent yields under solvent-free conditions. This methodology offers significant improvements for the synthesis of coumarins with regard to the yield of products, simplicity in operation, and green aspects by avoiding toxic catalysts and solvents.     

胶矾水中明矾对宣纸中纤维素、碳酸钙和明胶的影响

胶矾水是中国传统书画修复和装裱材料,但过量使用明矾会引起宣纸不同程度的酸化。为了解胶矾水中明矾对宣纸中不同成分的影响,明确传统胶矾水中明矾用量范围,减少其对宣纸的危害,采用傅里叶变换衰减全反射红外光谱(ATR-FTIR)和X射线衍射(XRD)研究了明矾对宣纸中纤维素和碳酸钙的影响,并将傅里叶退卷积和二阶导曲线拟合的方法引入研究明矾对宣纸中明胶蛋白质二级结构的影响。XRD和ATR-FTIR结果表明明矾会不同程度溶解纸张中的结晶纤维素、非结晶纤维素和CaCO₃(生成CaSO₄),在明矾浓度超过5 Wt%后成分变化最剧烈。傅里叶退卷积和二阶导曲线拟合结果表明明矾会使宣纸中明胶蛋白质二级结构改变,使α-螺旋结构、β-转向结构和γ-随机结构向β-折叠结构转变。在明矾浓度超过5 Wt%后,蛋白质二级结构发生剧烈变化。研究得出了明矾对宣纸中不同成分的影响,在最小干预的文物保护原则基础上给出了明矾用量范围,为纸质文物中蛋白质二级结构研究引入了一种新方法,扩大了ATR-FTIR在纸质文物中的研究和应用范围。