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1.
1INTRODUCTIONInthepastfewyears,potassiumchannelacti-vatorshavegainedincreasingattentionbecauseoftheirclinicalpotentialapplicationsinvariousdiseases.Oneofthemostpotentcompoundsamongthisnewclassofdrugsisthebenzopyranderivativecroma-kalim[1~4].Benzopyranaswellasitsderivativesex-hibitsextensivepharmacologicalandbiologicalacti-vities[5],suchasantibacterialactivities[6,,antitumor7]activity[8],hypotensiveeffect[9],antiproliferationef-fect[10],etc.Thetitlecompoundbearingabenzo-pyranstructuraluni…  相似文献   
2.
在微波辐射下以芳醛、1,3-环己二酮或达米酮和氨基吡唑为原料, 用乙二醇作能量转移剂, 三组分“一锅法”快速合成了一系列吡唑[5,4-b]并喹啉类化合物. 该方法速度快(30~90 s), 产率高(88%~98%), 环境友好. 产物结构通过红外光谱、核磁共振谱和元素分析证实, 化合物4e的单晶经X射线衍射分析, 进一步确证了产物结构.  相似文献   
3.
A facile one-pot synthesis of 5-(trifluoromethyl)-4,7-dihydrotetrazolo[1,5-a]pyrimidine derivatives is described via a three-component reaction of aldehydes with 5-aminotetrazole and ethyl 4,4,4-trifluoro-3-oxobutanoate or 4,4,4-trifluoro-1-phenylbutane-1,3-dione in ionic liquid. This method has the advantages of short synthetic route, operational simplicities, good yields, ecofriendliness, and recyclability of the solvent.  相似文献   
4.
A novel method for the synthesis of dibenzo[b,f]imidazo[1,2-d][1,4]oxazepine derivatives was described via cascade Csp2 N and Csp2 O bond constructions. It was a crossed double Ullmann reactions using 4,5-diaryl-2-(2-hydroxylphenyl)-1H-imidazole as the double nucleophilic centers in the presence of Cs2CO3, while 1-bromo-2-iodobenzene was used as a substrate catalyzed by CuI and o-phenanthroline in good yields.  相似文献   
5.
Aldehyde could undergo not only the subsequent condensation and cyclization with 2-aminothiophene-3-carboxamide to build a pyrimidine ring, but also a Friedel-Crafts alkylation reaction with thiophene moiety to give unexpected 6-benzyl-2-arylthieno[2,3-d]pyrimidin-4(3H)- ones in good yields catalyzed by concentrated HCl.  相似文献   
6.
以芳醛、4-羟基香豆素、丙二腈为原料,乙醇为能量转移剂,哌啶为催化剂,在微波辐射下一步合成了一系列2-氨基-3-氰基-4-芳基-4H,5H-吡喃-[3,2-c]苯并吡喃-5-酮,反应在40~60s时间内完成,产率60%~97%.  相似文献   
7.
1 INTRODUCTION Since the discovery of pharmacological effectsof 1,4-dihydropyridine (1,4-DHPs) as calcium mo-dulators[1], a great deal of work has been directedtowards the synthesis of 1,4-DHPs acting as cal-cium antagonists[2]. The chemical modifications onthe DHP ring, such as the introduction of differentsubstituents on heteroatoms[3], have allowed theexpansion of researches on structure-activity rela-tionship to have new insight into the molecularinteractions at the receptor l…  相似文献   
8.
A highly regio-selective Povarov reaction of an aromatic aldehyde, 1H-indazol-5-amine, and methyl 3-oxobutanoate catalyzed by iodine is described. This novel reaction selectively gave 3H-pyrazolo[4,3-f]quinolin-9-yl acetates, in high yield, rather than 3H-pyrazolo[4,3-f]quinoline-8-carboxylate derivatives. This procedure has the advantages of mild reaction conditions, high yields, metal-free catalyst, and high regio-selectivity.  相似文献   
9.
刘翠  庄启亚  李团结 《化学教育》2014,35(11):42-45
教学研究的发展及教学模式日趋多样化,导致教学设计方案多样化。研究不同类型的教学设计观,并设计出适合于不同教学情境的化学教案,有利于提升化学教师和师范生的教学设计能力。  相似文献   
10.
在[PdCl2(PPh3)2]催化下, 有机卤化锌试剂与芳香醛顺利地发生反应得到了较高产率的1,2-加成产物. 此方法避免了CuCN/2LiCl的使用, 为通过有机卤化锌试剂合成芳基取代的仲醇类化合物提供了一条简便的途径.  相似文献   
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