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1.
2.
Abstract

5-Alkoxycarbonyl-6H-1,3-thiazines, precursors of cephems, are prepared by alkylation of 2-methylene-3, 6-dihydro-2H-1,3-thiazines or by conversion of the carbaldehyde substituted at the 5 position of a 6H-1,3-thiazine. These compounds give access to dihydrothiazinic acids converted into cephems in the presence of methanesulfonyl chloride in anhydrous chloroform.

Les alkoxycarbonyl-5 6H-thiazines-1,3 précurseurs de céphèmes sont obtenues par alkylation de méthylène-2 2H-dihydro-3,6 thiazines-1,3 ou par conversion de la fonction carbaldéhyde d'une formyl-5 thiazine. Ces composés conduisent en deux étapes aux acides dihydrothiaziniques qui sont transformés en céphèmes par le chlorure de méthanesulfonyle en milieu anhydre.  相似文献   

3.
含氟杀菌剂5-氯-2,4,6-三氟-1,3-苯二腈的合成   总被引:10,自引:0,他引:10  
1 前言2 ,4,5 ,6-四氯 -1 ,3 -苯二腈 ,俗名百菌清 ( 1 ) ,是一种广谱、高效、安全的农林及工业用杀菌剂 ,对多种作物具有预防和治疗作用 ,其持效期长且稳定 ,可用于麦类、水稻、果树、蔬菜、花生、茶叶、橡胶、森林等多种作物的各种病害 ,还可以用于防治蚕体酵母霉病和僵病及制革等工业防霉[1] 。国内有云南化工厂等 1 8家工厂生产其原药、粉剂或乳油。其含氟衍生物研究尚不多 ,由于氟原子或含氟基团的导入 ,使化合物的挥发性、扩散性、相溶性及表面活性增加 ,而位阻影响不大 ,故能充分发挥在有机体内的脂溶性 ,对生物体的多种相态、对膜…  相似文献   

4.
A new cyclic monomer, 2-methyl-2-methoxycarbonyl-5-methylene-1,3-dioxolan-4-one,was synthesized successfully. The monomer and intermediate were characterized by ~1H NMR, ~(13)CNMR, INEPT(Intensive Nuclei Enhanced by Polarization Transfer) technique, IR and elementalanalysis. Anionic polymerization of the monomer was carried out in anhydrous THF at -70℃,and 9-fluorenyllithium was used as initiator. The polymer structure was determined by IR, NMRand elemental analysis. Molecular weight of the polymer was estimated by viscosity measurementin DMSO at 30℃.  相似文献   

5.
5-Methoxy- and 5-dimethylamino-1-methyl-3-oxidopyridiniums were shown to give the 1,3-dipolar cycloadducts widely with methyl acrylate, acrylonitrile, N-phenylmaleimide, styrene, phenylacetylene, cyclopentadiene, cyclopentene, diethyl azodicarboxylate and singlet oxygen.  相似文献   

6.
Abstract

Selenourea reacts with dialkyl acetylenedicarboxylates in acetone to form 1:1 adducts, which undergo a cyclization reaction to produce alkyl Z-2-(2-amino-4-oxo-1,3-selenazol-5(4H)-yliden) acetates in fairly good yields. The reaction is completely stereoselective.  相似文献   

7.
本文采用吡唑并[3,4-d]-1,3-噁嗪-6-酮衍生物(Ⅰ)与伯胺反应,合成了1-烃基-5-取代苯甲酰胺基-4-吡唑(N-取代)甲酰胺(Ⅱ);由LiAlH4,对Ⅱ分子中2个酰胺基的选择性还原合成了1-烃基-5-取代氨基-4-吡唑(N-取代)甲酰胺(Ⅲ).共合成新化合物23个,通过1HNMR、13CNMR、MS、IR等证明了它们的化学结构,初步生物活性测定表明化合物Ⅱ具有一定的抗癌活性和农药活性。  相似文献   

8.
Cycloaddition of 2-phenacyl-1H-benzimidazole to 2-phenyl-or 2-methyl-4-arylidene-1,3-oxazol-5-ones occurs regioselectively to form the previously unknown N-(3-aryl-4-benzoyl-1-oxo-1,2,3,4-tetrahydropyrido[1,2-a]benzimidazol-2-yl)benz-and-acetamides. The analogous cycloaddition of the 2-acetonyl-1H-benzimidazole is complicated by prototropic isomerization and leads to the corresponding 1,2,3,5-tetrahydropyrido[1,2-a]benzimidazole. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 78, pp. 1008–1014, July, 2007.  相似文献   

9.
为得到3,4-二取代双环硫化磷酸酯的中间体5-叔丁基-5-(1'-羟基-2'-甲基丙基)-2,2-二甲基-1,3-二氧六环, 通过5-叔丁基-5-甲酰基-2,2-二甲基-1,3-二氧六环与异丙基溴化镁反应没有得到目标化合物, 而得到了还原产物, 改用异丙基锂代替异丙基溴化镁反应后得到目标化合物, 通过超声波辅助反应, 大幅度提高了反应收率.  相似文献   

10.

Tiourea reacts with dialkyl acetylenedicarboxylates in solventless conditions to form 1:1 adducts, which undergo a cyclization reaction to produce alkyl Z-2-(2-amino-4-oxo-1,3-thiazol-5(4H)-yliden)acetates in fairly good yields. The stereochemistry of the ethyl Z-2-(2-amino-4-oxo-1,3-thiazol-5(4H)-yliden)acetate was established by the use of X-ray single crystal structure analysis. The reaction is completely stereoselective.  相似文献   

11.
X-Ray Crystal Structure Determination of 1,3-Bis(diethylamino)-1,3-dibenzyl-2,4-diphenyl-1λ5, 3λ5-diphosphete Benzylidene-diethylamino-benzylfuorophosphorane, 1 , reacts with lithium bis(trimethylsilyl)amide to give the title compounds 2 and 1-diethylamino-2,3-diphenylphosphirane, 3 . Only one of the stereoisomers of 2 is formed in which the two benzyl groups are located on the same side of the planar four-membered ring. 2 crystallizes in the monoclinic space group P21/n.  相似文献   

12.
A number of new dialkyl 5-(aryl)-1-phenyl-1H-prazole-3,4-dicarboxylate derivatives have been prepared regiospecifically in moderate to good yield from the cyclocondensation reaction of dialkyl (E)-2-(dialkoxyphosphoryl)-3-(aroyl)-2-butenedioate, derived from the reaction between trimethyl phosphite, an acetylenic ester, and an aroyl chloride, with phenylhydrazine. The reaction is four-component and is carried out under reflux conditions in dry toluene.  相似文献   

13.
The behavior of 5-amino-2-phenyl- and 5-amino-1-methyl-2-phenylindoles in reactions with acetoacetic, trifluoroacetoacetic, and ethoxymethylenemalonic esters, leading to the preparation of pyrrolo[2,3-g]- and pyrrolo[3,2-f]quinolines with functional substituents has been studied.  相似文献   

14.
Abstract

Reaction of 2-mercaptopropargylquinazoline-4-one with various aryliodides catalyzed by Pd–Cu leads to the regioselective formation of 1-arylsubstituted-5H-[1,3]thiazolo-[3,2-a]quinazoline-5-ones.

GRAPHICAL ABSTRACT   相似文献   

15.
El-Shekeil  A.G  Babaqi  A.S  Hassan  M.A  Shiba  S.A 《化学学报》1988,46(7):724-726
报导了1-芳基-3-(5-氯代-1,3-二苯基-1H-4-吡唑基)-2,3-环氧-1-丙酮的重排反应, 生成β-(4,5-二氢-1,3-二苯基-5-酮-1H-4-吡唑基)-α-羟基-α-P-甲苯基丙酸, 讨论了反应机理, 并用红外光谱, 核磁共振氢谱, 碳十三核磁共振和微量分析证实了结构.  相似文献   

16.
17.
李德江  孙碧海  李斌 《合成化学》2004,12(2):191-193
以5-氨基-1H1,2,4-三氮唑-3-羧酸乙酯为原料,经Sandmeyer反应合成了5-X-1H-1,2,4-三氮唑-3-羧酸乙酯(X=C1,Br,I)(1a-1c),1a-1c再分别与α-2′,4′-二氟苯乙酮反应合成了3个5-卤代-1-1H-1,2,4-三氮唑-3-羧酸乙酯衍生物(2a-2c),其结构通过元素分析,IR,UV和^1H NMR进行了表征。  相似文献   

18.
The reaction of 6-amino-1,3-dimethylpyrrolo[3,4-d]pyrimidine-2,4-dione with 1,3-diketones leads to formation of predominantly pyrimido[4',5':3,4]pyrrolo[1,2-b]pyridazine-2,4(1H,3H)-diones and, to a lesser extent, pyrimido[5',4':3,4]pyrrolo[1,2-b]pyridazine-1,3(2H,4H)-diones. The ease and direction of the cyclization reaction suggests a very -electron rich pyrrole ring in the initial state, especially in the position 7.  相似文献   

19.
20.
A copper-catalyzed [5+1] cycloaddition reaction of terminal alkynes with diazo esters for the rapid construction of protected naphthalen-1(2H)-one derivatives in moderate to good yields has been disclosed along with good functional group compatibility and a broad substrate scope. The mechanistic investigations reveal that this tandem cyclization process proceeds through a Cu(I)-catalyzed coupling of terminal alkyne with diazoacetate, a 1,5-H shift process and a thermally induced pericyclic reaction via an allene intermediate. The synthetic utility and the further transformations of the obtained cycloadduct to naphthalenone, naphthol and dihydronaphthol have been also presented in this paper.   相似文献   

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