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1.
《合成通讯》2013,43(23):4417-4420
Abstract

An efficient synthesis of [3H] dapsone at high specific activity is described.  相似文献   

2.
Realizing a need for labeled dirhodium tetraacetate [Rh2/OAc/4] for binding studies by the equilibrium dialysis procedure, we have established a method for the preparation and purification of [3H]Rh2/OAc/4. This is obtained with a tritium label of a sufficiently high specific activity in the methyl group of acetate residues. The method consists of replacement of the existing acetate bridge by [3H]OAc. A typical preparation involves refluxing Rh2/OAc/4 with [3H]NaOAc in dry ethanol at 80°C for 6 h. The reaction time is critical for obtaining the product with a high specific activity. A simple purification of reaction products yields the compound of interest with a high specific activity, i. e., 315±10 Ci per mol of Rh2/OAc/4 and in satisfactory yield /87% of the starting material., This labeled material can be synthesized with greatly increased specific activity /of tritium in acetate groups/ by employing [3H]NaOAc without prior dilution. The labeled Rh2/OAc/4 is stable and yields a characteristic product with adenylic acid.  相似文献   

3.
The synthesis of two new derivatives of 3H[1,2]diazepino[5,6-b]indole, 5 and 11 , and one new derivative of 3H[1,2]diazepino[4,5-b]indole, 16 , are described. Compound 5 was obtained by the reaction of methyl 2-(3-methoxycarbonyl-1-methylindole)acetate 2 , with hydrazine. Compound 11 was obtained in two ways from ethyl 2-(1-methylindole)acetate ( 8 ) by formylation and reaction with hydrazine. Compound 16 was obtained treating 3-(2-ethoxycarbonylindole)acetonitrile ( 14 ) with hydrazine.  相似文献   

4.
The synthesis of [1,2-3H2]-polystyrene consisted of a two step reaction. First catalytic tritium gas addition to phenylacetylene was used to prepare [1,2-3H2]-styrene and then it was polymerized to [1,2-3H2]-polystyrene in the present of an initiator.  相似文献   

5.
Information is given on the synthesis of tritium-labeled UDPG by the successive transformation of D-[1-3H]glucose or D-[6-3H]glucose by the action of the enzymes hexokinase (EC 2.7.1.1), phosphoglucomutase (EC 2.7.5.1), and UDPG-pyrophosphorylase (EC 2.7.7.9) under conditions ensuring the retention of the tritium label. Methods of obtaining tritium-labelled substrates and intermediate products of their enzymatic transformations in the synthesis of [3H]UDPG are discussed.V. G. Khlopin Radium Institute, Leningrad. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 125–128, January–February, 1987.  相似文献   

6.
The title compound ( 14 ), a representative of a novel ring system, was prepared from 9H-carbazole-1-carboxylic acid 1-methylhydrazide ( 7 ) and triethyl orthoformate. Attempted cyclization of 7 with triethyl orthoacetate led only to 9H-carbazole-l-carboxylic acid 2-(l-ethoxyethylidene)-l-methylhydrazide ( 16 ). Treatment of 16 with trifluoroacetic acid gave 9H-carbazole- 1 -carboxylic acid ( 12 ). A postulated mechanism for this transformation was supported by studies with model compounds. A new synthesis of 1 -benzoyl-2-methylhydrazine ( 24 ), using 1-acetyl-1-methylhydrazine ( 22 ) as a synthon, is described.  相似文献   

7.
8.
1mTRODUCTIONWehavereportedsomenuorancomPoundswithdifferentsubstitutedgroups"~'>.Thispaperdescribesacontinuationofourinvestigationonthenuoranderivatives.ThecrystalstructureofthecomPOundC,zHzsNzo'(I)(whereRl-NEt2,R2=H,R3=NHCHzCoCeHs,R`=H)wasdeterminedbyX-raydiffractionmethod.Inaddition,wealsocomparethetitlecomPOundwithotherfluorancomPounds.2EXPERIMENTAL2.1SynthesisAmixtureof2'-carboxy-4-diethylamino-2-hydrzophenoneandP-hydroxy-acetanilide(molarratio1:l)insulfuricacidwasheated…  相似文献   

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10.
4,5-Dihydro-1H,3H-thieno[3,4-c]thiophene and 4,5-dihydro-1H,3H-thieno[3,4-c]furan were synthesized by retro Diels-Alder reactions under flash vacuum thermolysis conditions.  相似文献   

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13.
The syntheses of 24-methylidene[24-14C]cholesterol ( 7a ) and of 24-methylidene[7-3H]cholesterol ( 7b ) from commercially available (20S)-3-oxopregn-4-ene-20-carbaldehyde ( 1 ) are described. The method also provides simple preparations of 3β-acetoxy[24-14C]chol-5-en-24-oic acid ( 4 ) and 24-oxocholest-5-en-3β-yl acetate ( 6b ).  相似文献   

14.
15.
三唑类衍生物是重要的化工和药物合成中间体,而稠合三唑类衍生物因其独特的生理活性更是得到了广泛关注[1-2],其中3-三氟甲基-5,6,7,8-四氢[1,2,4]三唑并[4,3-α]哌嗪与β-氨基酸缩合得到的化合物是一类重要的二肽基肽酶-Ⅳ抑制剂 [3-4],可作为2型糖尿病的治疗药物,如2006年经美国FDA批准在美国上市的西他列汀(sitagliptin),此外二肽基肽酶-Ⅳ抑制剂还可用于肥胖症和高血压等疾病的预防和治疗[5].  相似文献   

16.
The title compound 3b was synthesized in three steps from acetaminothioacetamide ( 4b ) in 15% overall yield. This represents the first synthesis of a 2-guanidinomethylthiazole, which is a homolog of an important pharmacophore, 2-guanidinothiazole.  相似文献   

17.
林墀昌  陈功 《化学学报》1988,46(5):439-444
本文报道MoCl3.3H2O与乙酸作用生成三核钼簇合物H[H2O]3[Mo3O(OAc)3Cl6]的反应, 并用X射线单晶结构分析方法测定了簇合物的晶体结构, 结晶学参数. 结构分析结果表明该化合物阴离子为单氧帽等边三角形三核钼簇合阴离子, Mo-Mo平均距离2.569埃.对簇骼单元[Mo3O(μ-Cl)3Cl3]^2^+进行简正坐标分析. 从理论上对振动光谱谱带进行了归属. 10条IR谱带的观测和计算频率的平均偏差为1.15%. 本文讨论了特征谱带(包括金属键)的归属和力常数的合理性.  相似文献   

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19.
[1,2,3]Triazolo[4,5-d]pyrimidine 3-oxides were synthesized by replacement of the amino group in 6-aminouracil by hydroxyamino, coupling of the resulting 6-hydroxyaminopyrimidine with benzenediazonium salts, and oxidation of 6-hydroxyamino-5-phenylazouracils with a solution of K3[Fe(CN)6] in water.  相似文献   

20.
3:4-Fused furocoumarins and pyrrolocoumarins are synthesised from 3-hydroxy and 3-benzamido-substituted coumarins by a novel two step sequence.  相似文献   

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