ICP-AES法测定内蒙古地区六种沙生木本植物中金属元素

采用ICP-AES法分别对内蒙古地区梭梭、小叶锦鸡儿、沙冬青、红柳、沙枣和沙柳等六种沙生木本植物中金属元素进行了测定和分析。该方法的加标回收率为94.98％～120.25％,RSD＜3.4％,具有良好的准确度和精密度。结果表明,常量元素Ca,K,Mg,Na,Al及植物生命活动所必需的微量元素Fe,Mn,Cu,Zn在六种沙生木本植物中表现为不同的含量顺序,且Fe,Mn,Cu,Zn四种元素的含量均低于陆生高等植物的平均含量。该测定结果为改善西部地区生态环境,选择优良防风固沙树种提供可靠的数据和理论依据。     

Structure of 22-deoxocucurbitacins isolated fromBryonia alba andEcbalium elaterium

22-Deoxocucurbitacin D (II), dihydrocucurbitacin B, cucurbitacin L, and the previously unknown rhamnoglucosyl-22-deoxo-16,23-epoxycucurbitosides A (III) and B (IV) have been isolated from the roots ofBryonia alba and identified. Glucoside (III) has also been identified in the fruit ofEcbalium elaterium L.A. L. Mndzhoyan Institute of Fine Organic Chemistry, Academy of Sciences of the Armenian SSR, Erevan, Translated from Khimiya Prirodnyk Soedinenii, No. 5, pp. 679–687, September–October, 1985.     

A new intramolecular recyclization in water‐base cleavage reaction of 2,2‐dialkyl‐4‐hydroxymethylbenz[f]iso indolinium bromides and chlorides

The water‐base cleavage reaction of 2,2‐dialkyl‐4‐hydroxymethylbenz[f]isoindolinium bromides and chlorides (2b‐g) and (4a‐g) was investigated. It was established that the above‐mentioned salts in water‐base cleavage reaction undergo intramolecular recyclization. As a result 1,3‐dihydro‐4‐dialkylaminomethyl‐naphto[1,2‐c]furans (5a‐g) are obtained in 62‐72% yields. The same products in 65‐70% yields may be obtained by step cyclization cleavage reaction of dialkyl‐4‐hydroxybutyn‐2‐yl‐(3‐phenylpropargyl) ammonium salts (1b‐g) and (3a‐g) , as well. The structure of the resulting amines 5a‐g are determined and approved by X‐ray diffraction, nmr and ir spectroscopic methods.     

Formation of pyrrolinium derivatives in the bromination reaction of <Emphasis Type=Italic>N</Emphasis>,<Emphasis Type=Italic>N</Emphasis>-dipropargyl ammonium salts

Bromination of ammonium salts containing two propargyl groups afforded bromine-substituted derivatives of pyrrolinium salts. The reactions of piperidinium and morpholinium analogs resulted in spirocyclic ammonium salts.     

Synthesis and Antioxidant Activity of Ethyl 2-Amino-6-cyano-6-phenyl-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylates and 3-Amino-4-oxo-7-phenyl-3,4,5,6,7,8-hexahydrobenzo[4,5]thieno[2,3-d]pyrimidine-7-carbonitriles

Russian Journal of Organic Chemistry - Gewald reaction of 4-oxo-1-phenylcyclohexane-1-carbonitrile with ethyl cyanoacetate and elemental sulfur in the presence of diethylamine afforded ethyl...     

Unusual dimroth rearrangement of an allyl-1,2,4-triazolo[4,3-c]pyrimidine

Refluxing 4-allyl-7-benzyl-5-methyl-1,2,4-triazolo[4,3-c]pyrimidine in an alcohol solution of sodium ethylate causes a Dimroth rearrangement together with a prototropic isomerization of the allyl fragment to give 7-benzyl-5-methyl-4-propenyl-1,2,4-triazolo[2,3-c]pyrimidine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1545–1547, November, 1993     

Base-Catalyzed Intramolecular Cycloaddition of Dialkyl(4-hydroxybut-2-yn-1-yl)[3-(4-bromophenyl)prop-2-yn-1-yl]ammonuim Chlorides and Recyclization of the Products

Russian Journal of Organic Chemistry - Dialkyl(4-hydroxybut-2-yn-1-yl)[3-(4-bromophenyl)prop-2-yn-1-yl]ammonium chlorides in the presence of 2 equiv of potassium hydroxide at room temperature...     

Substituted 2-(2-Arylethenyl)quinazolines. Synthesis and Structure

Russian Journal of Organic Chemistry - The reaction of 2-methyl-4H-3,1-benzoxazin-4-one and its 6-iodo derivatives with a number of amines in polyphosphoric acid afforded 3- and 3,6-substituted...