采用密度泛函理论中的广义梯度近似（DFT/GGA）方法,在PW91/DNP水平上研究了21种2,3-二取代喹唑啉-4（3H）-酮化合物的结构、化学活性和前线轨道.结果表明：此类化合物的能隙Eg大部分都在3.50-3.60 e V之间,其中在喹唑啉环3位上取代甲...采用密度泛函理论中的广义梯度近似（DFT/GGA）方法,在PW91/DNP水平上研究了21种2,3-二取代喹唑啉-4（3H）-酮化合物的结构、化学活性和前线轨道.结果表明：此类化合物的能隙Eg大部分都在3.50-3.60 e V之间,其中在喹唑啉环3位上取代甲氧基苄基,或是在8位上取代甲基,化合物的能隙降低,而且甲氧基在苄基的间位比对位降低得更厉害.通过比较还发现,2,3-二取代喹唑啉-4（3H）-酮化合物对水稻纹枯菌（Rhizoctonia solani bacteria）的杀菌活性与哌啶并噻吩并嘧啶酮衍生物对水稻纹枯菌的杀菌活性相当,而哌啶并噻吩并嘧啶酮衍生物比2,3-二取代喹唑啉-4（3H）-酮化合物对苹果轮纹病（Botryospuaeria gregaria bacteria）杀菌活性好.展开更多
Dihydroquinazolin-4(3H)-ones were synthesized by the reaction of o-nitrobenzamides with aromatic aldehydes or cyclones promoted by the low-valent titanium reagent(TiCl 4-Zn system). The products were characterized by ...Dihydroquinazolin-4(3H)-ones were synthesized by the reaction of o-nitrobenzamides with aromatic aldehydes or cyclones promoted by the low-valent titanium reagent(TiCl 4-Zn system). The products were characterized by elementary analysis, IR, 1H NMR and X-ray single crystal diffraction. This method possesses the advantages of easily accessible starting materials, convenient manipulation and moderate to high yields.展开更多
2-Amino-5-methylbenzoic acid（1） was acylated with acyl chlorides,then heated（together） with（acetic） anhydride to give 2-phenyl or 2-benzyl-6-methylbenzoxazin-4-one（3a3b）,while compound 1 was （reacted） with p...2-Amino-5-methylbenzoic acid（1） was acylated with acyl chlorides,then heated（together） with（acetic） anhydride to give 2-phenyl or 2-benzyl-6-methylbenzoxazin-4-one（3a3b）,while compound 1 was （reacted） with propanoic anhydride or trifluoroacetic anhydride to give 2-ethyl or 2-trifluoromethyl-6-methylbenzoxazin-4-one（3c3d） directly. Then,2-substituted 6-methylbenzoxazin-4-ones（3a3d） were heated together with formamide to afford 2-substituted 6-methyl-4（3H）-quinazolinones（4a4d）,which were（converted） into the title compounds（5a5d） via brominating with N-bromosuccinimide in the presence of （PhCOO）2.The structures of all the intermediates and final products were confirmed with ESI-MS,1H NMR and elemental analysis.展开更多
3,4-Dihydropyrimidin-2-(1H)-ones were synthesized in high yields by a one-pot cyclocondensation of aldehyde,1,3-dicarbonyl compound,and urea or thiourea using copper o-toluenesulfonate as a catalyst under solvent-free...3,4-Dihydropyrimidin-2-(1H)-ones were synthesized in high yields by a one-pot cyclocondensation of aldehyde,1,3-dicarbonyl compound,and urea or thiourea using copper o-toluenesulfonate as a catalyst under solvent-free conditions at 90℃.Effects of molar ratio of reactants,amount of catalyst,and reaction temperature on the yields of 3,4-dihydropyrimidin-2-(1H)-ones were investigated.The results showed that at the condition of naldehyde∶n1,3-dicarbonyl compounds∶nurea(or thiourea)=1∶1.2∶1.5,1 mol% catalyst(molar percent of aldehyde),2.0 h at 90℃,the yields of products were 51-96%.After reaction,the catalyst could be reused for four times without distinct loss of catalytic activity.展开更多
文摘Dihydroquinazolin-4(3H)-ones were synthesized by the reaction of o-nitrobenzamides with aromatic aldehydes or cyclones promoted by the low-valent titanium reagent(TiCl 4-Zn system). The products were characterized by elementary analysis, IR, 1H NMR and X-ray single crystal diffraction. This method possesses the advantages of easily accessible starting materials, convenient manipulation and moderate to high yields.
文摘2-Amino-5-methylbenzoic acid（1） was acylated with acyl chlorides,then heated（together） with（acetic） anhydride to give 2-phenyl or 2-benzyl-6-methylbenzoxazin-4-one（3a3b）,while compound 1 was （reacted） with propanoic anhydride or trifluoroacetic anhydride to give 2-ethyl or 2-trifluoromethyl-6-methylbenzoxazin-4-one（3c3d） directly. Then,2-substituted 6-methylbenzoxazin-4-ones（3a3d） were heated together with formamide to afford 2-substituted 6-methyl-4（3H）-quinazolinones（4a4d）,which were（converted） into the title compounds（5a5d） via brominating with N-bromosuccinimide in the presence of （PhCOO）2.The structures of all the intermediates and final products were confirmed with ESI-MS,1H NMR and elemental analysis.
文摘3,4-Dihydropyrimidin-2-(1H)-ones were synthesized in high yields by a one-pot cyclocondensation of aldehyde,1,3-dicarbonyl compound,and urea or thiourea using copper o-toluenesulfonate as a catalyst under solvent-free conditions at 90℃.Effects of molar ratio of reactants,amount of catalyst,and reaction temperature on the yields of 3,4-dihydropyrimidin-2-(1H)-ones were investigated.The results showed that at the condition of naldehyde∶n1,3-dicarbonyl compounds∶nurea(or thiourea)=1∶1.2∶1.5,1 mol% catalyst(molar percent of aldehyde),2.0 h at 90℃,the yields of products were 51-96%.After reaction,the catalyst could be reused for four times without distinct loss of catalytic activity.
