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1.
山芝麻 (Helicteresangustifolia L inn.)是梧桐科 (Sterculiaceae)山芝麻属植物 ,主要分布在广东、广西、云南及长江以南各省 ,用以治疗感冒发热、麻疹、疟疾和疔疮等症 [1] .王明时等 [2 ,3]曾从该植物中分离出 3个三萜类化合物和 1个萘醌化合物 .为进一步寻找有效成分 ,我们从山芝麻中又分离到 2个新的三萜化合物 1和 2 ,用波谱方法测定了其化学结构 .1 实验部分1 .1 仪器与材料 北京泰克仪器公司的双目镜 X-6型显微熔点仪 ;EQUINOX-55(Bruker)红外光谱仪 ;Varian Unity INOVA 50 0型核磁共振仪 (TMS为内标 ) ;VG Autospec-… 相似文献
2.
苦豆籽中总生物碱的含量测定 总被引:1,自引:0,他引:1
苦豆籽系槐科植物苦豆子 (Sophraalopecaroides)的成熟种子。从苦豆籽中分离得到了 2 0余种生物碱[1 ] ,具有广泛的生理活性 ,药用价值很高。苦豆子总生物碱的含量测定有重量法[2 ] ,酸碱滴定法[3] ,因苦豆子生物碱结构多属于喹啉联啶类衍生物 ,可在pH7.6缓冲液中与溴麝香草酚蓝形成离子对 ,经氯仿提取后于 42 0nm进行比色测定。我们采用这种酸性染料分光光度法[4] 进行了苦豆籽胶囊中总生物碱的含量测定 ,为其质量标准的测定提供了依据。1 实验部分1 .1 仪器 ,药品72 1型分光光度计、PH 2S型酸度计 ,槐果碱(C… 相似文献
3.
合成了 [Ni( dmit) ( dmise) ]n-( n=2 ,1 ,0 )型混合配体配合物 ,用电结晶法制得 [BEDT-TTF]-[Ni( dmit) ( dmise) ]电荷转移盐 ,并用 EA、IR、ESR对目标产物进行了表征 .2 5℃测得化合物 [Ni( dmit) -( dmise) ]和 [BEDT-TTF][Ni( dmit) ( dmise) ]的电导率分别为 0 .2 9和 5.6× 1 0 -3 Ω-1· cm-1.2 98~ 1 0 3 K温度范围内变温电导曲线显示 :化合物 [Ni( dmit) ( dmise) ]具有典型的半导体性质 . 相似文献
4.
合成了两种固态稀土丙氨酸配合物[Ho2(Ala)4(H2O)8]Cl6和[ErY(Ala)4(H2O)8](ClO4)6 (Ala为丙氨酸),用量热和热分析方法研究了这两种配合物的热力学性质.用全自动高精密绝热量热计测定了在78~377 K温区内的低温热容.对于[Ho2(Ala)4(H2O)8]Cl6,在214~255 K温区内发现一固-固相变,其相变温度为235.09 K.对于[ErY(Ala)4(H2O)8](ClO4)6,在99~121 K温区内也发现一固-固相变,其相变温度为115.78 K. [Ho2(Ala)4(H2O)8]Cl6固-固相变焓为3.02 kJ• mol-1,相变熵为12.83 J•K-1•mol-1; [ErY(Ala)4(H2O)8](ClO4)6 固-固相变焓为1.96 kJ•mol-1,相变熵为16.90 J•K-1•mol-1.同时,用TG技术在40~800 ℃温区研究了两配合物的热稳定性.由TG/DTG曲线分析可知, [Ho2(Ala)4(H2O)8]Cl6从80 ℃到479 ℃热分解分两步完成, [ErY(Ala)4(H2O)8](ClO4)6从120 ℃到430 ℃热分解分三步完成. 相似文献
5.
2,4,6-三硝基间苯二酚钡一水化合物的热分解动力学(英) 总被引:1,自引:0,他引:1
0IntroductionBarium2,4,6鄄trinitroresorecinatemonohydrate,Ba(TNR)·H2O,hasgooddetonatingpropertiesandissensitivetoflame.Itcanbeusedasinitiatingagent,igniterpowderordelaypowder.Itspreparation[1],pro鄄perties[1],crystalstructure[1]andthermalbehavior[2]haveb… 相似文献
6.
用量子化学密度泛函理论(DFT)的B3LYP方法对高锰酸根离子与丙烯酸的环加成反应机理进行了系统研究, 全参数优化了反应势能面上各驻点的几何构型、振动频率和能量. 计算结果表明: 反应有两个竞争通道, 即[2+3]反应通道和[2+2]反应通道, 其中[2+3]通道比[2+2]通道的反应势垒降低了183.89 kJ/mol, 并通过在高锰酸根的氧原子上配位一个或两个BF3分子来研究BF3分子对反应体系的活化效应, 结合两个BF3分子使得[2+3]通道的反应势垒降低为23.97 kJ/mol, 则有利于反应按该通道进行, 然而[2+2]通道的反应势垒仍较高(>195 kJ/mol).这进一步表明该反应体系中加入一定量BF3能提高高锰酸氧化烯烃双键的化学活性. 相似文献
7.
以十六烷基三甲基溴化铵(CTAB)/正丁醇/正辛烷/硝酸钕[Nd(NO3)3]溶液(碳酸钠溶液)所组成的反相微乳液为反应介质, 采用微乳液溶剂热法合成了Nd2(CO3)3·8H2O, 并考察了水/核比([H2O]/[CTAB])和Nd(NO3)3的浓度对其形貌和尺寸的影响. 利用X射线衍射(XRD)、 热分析(DSC-TGA)、 扫描电子显微镜(SEM)和透射电子显微镜(TEM)等对Nd2(CO3)3·8H2O的晶型、 形貌及尺寸进行了表征, 并提出了不同形貌Nd2(CO3)3·8H2O形成的可能机理. 结果表明, 随着水/核比的增大, Nd2(CO3)3·8H2O的形貌从多面体变成鱼尾状, 再变成针状; 随着Nd(NO3)3浓度的增大, 针状Nd2(CO3)3·8H2O的尺寸逐渐减小. 相似文献
8.
朝鲜淫羊藿中生物碱类新成分的分离提取及结构鉴定 总被引:8,自引:0,他引:8
淫羊藿系小檗科淫羊藿属植物 ,具有补肾壮阳、强筋骨、祛风湿之功效 .现代药理研究表明 ,它还具有防治骨质疏松和提高免疫功能等作用 .2 0 0 0年版中国药典收载了 5种淫羊藿属植物 ,朝鲜淫羊藿为其中一种 ,是长白山道地中药材之一 .朝鲜淫羊藿中化学成分的研究多集中在黄酮类化合物方面 [1~ 6 ] ,而对其生物碱类化合物的研究较少 [7,8] .本文对朝鲜淫羊藿中生物碱类化合物进行了研究 ,并发现了一种新的生物碱 (6-羟基 -1 1 ,1 2 -二甲氧基 -2 ,2 -二甲基 -1 ,8-二氧 -1 ,3 ,4,8-四氢 -2 H -7-氧杂 -2 -氮 -苯并 [c]菲 ) ,采用核磁共振波… 相似文献
9.
合成了苯并 15 冠 5、二苯并 18 冠 6与Na2 [Pt(SCN) 6]的配合物 :[Na(B15 C 5 ) ]2 [Pt(SCN) 6](1) ,[Na(DB18 C 6 ) ]2 [Pt(SCN) 6](2 ) ,并通过元素分析、红外光谱、单晶X射线衍射进行了表征 .1为单斜晶系 ,空间群P2 1/c,a =1.0 974(5 )nm ,b =1.5 187(7)nm ,c=1.36 32 (6 )nm ,β =96 .40 7(7)°,V =2 .2 5 6 8(18)nm3 ,Z =2 ,Dcalcd=1.746g/cm3 ,F(0 0 0 ) =1184,R1=0 .0 35 7,wR2 =0 .0 86 8.2为三斜晶系 ,空间群P1- ,a =1.2 5 0 0 (3)nm ,b =1.2 82 5 (3)nm ,c=1.934 2 (4 )nm ,α=10 6 .82 (3)° ,β =10 2 .5 1(3)° ,γ =10 3.0 4(3)°,V =2 .75 6 2nm3 ,Z =2 ,Dcalcd=1.5 79g/cm3 ,F(0 0 0 ) =1316 ,R1=0 .0 36 4,wR2 =0 .0 771.配合物分别由两个 [Na(B15 C 5 ) ]+ ,[Na(DB18 C 6 ) ]+ 配阳离子和一个[Pt(SCN) 6]2 -配阴离子组成 .配阳离子和配阴离子通过Na—N键形成二维网状结构 相似文献
10.
采用无机阴离子诱导方法,以具有平面构型的[Pd_nCl_m]~(2-)阴离子为结构导向试剂,成功制备了3种具有框架结构特征的瓜环基超分子化合物:{Na_2(H_2O)_6TMeQ[6]}[Pd_2Cl_6]·3H_2O (1)、(H_3O)_2{CyH_5Q[5]}[Pd_2Cl_6]·3H_2O (2)及(H_3O)_2{Q[5]}[PdCl_4]·23H_2O (3)。X射线单晶衍射的结果表明:在1中,Na+离子与TMeQ[6]端口羰基氧直接配位形成一维结构的超分子链,在[Pd_2Cl_6]~(2-)阴离子与TMeQ[6]的外壁作用下,进一步构筑形成三维的框架结构;在2中,在[Pd_2Cl_6]~(2-)阴离子与CyH_5Q[5]的外壁作用下,CyH_5Q[5]以一维链有序排列,且4条CyH_5Q[5]分子链可堆砌成一孔道,孔道中填充了[Pd_2Cl_6]~(2-)阴离子,最终形成三维框架结构;在3中,8个[PdCl_4]~(2-)阴离子与4个Q[5]分子通过瓜环外壁相互作用,形成二维层状框架结构,层与层之间再通过非共价键作用力,最终形成三维层状框架结构。在这3种瓜环基超分子框架化合物中,[Pd_nCl_m]~(2-)阴离子促进了瓜环分子有序化排列,形成了具有框架结构特征的自组装体。这种主要驱动力来源于瓜环的外壁作用,即瓜环"正电性外壁"与[Pd_nCl_m]~(2-)阴离子间的离子偶极作用。 相似文献
11.
ErythrinaarborescensRoxb.belongstoErythrinagenusofPapilionaceaefamilyplants,andiswidelydistributedintropicalandsubtropicalregionsoftheworld,aswellasinthesouthandsouth-westofChina'.AsaChinesefolkmedicine,itsrootandstemareusedtotreatrheumatismanddysentery'.TheErythrinaalkaloids,normallyaC.,tetracyclicspiroaminesystem,erythrinanel,arethecharacteristicconstituentsinErylhrinagenusandabout100erythrinaalkaloidshavebeensofarreportedfromthisgenusplants'-'.MostoftheseErythrinaalkaloidshaveatetrahydr… 相似文献
12.
Joanna J. Sajkowska-Kozielewicz Pawe Kozielewicz Katerina Makarova Marcin Stocki Nicholas M. Barnes Katarzyna Paradowska 《Molecules (Basel, Switzerland)》2021,26(1)
A new alkaloid, geissospermiculatine was characterized in Geissospermum reticulatum A. H. Gentry bark (Apocynaceae). Here, following a simplified isolation protocol, the structure of the alkaloid was elucidated through GC-MS, LC-MS/MS, 1D, and 2D NMR (COSY, ROESY, HSQC, HMBC, 1H-15N HMBC). Cytotoxic properties were evaluated in vitro on malignant THP-1 cells, and the results demonstrated that the cytotoxicity of the alkaloid (30 μg/mL) was comparable with staurosporine (10 μM). Additionally, the toxicity was tested on zebrafish (Danio rerio) embryos in vivo by monitoring their development (0–72 h); toxicity was not evident at 30 μg/mL. 相似文献
13.
A new alkaloid, 2-methylimidazo[1,5-b]isoquinoline-1,3,5(2H)-trione, was isolated from the EtOAc extract of the marine-derived fungus Hypocrea virens. Its structure was confirmed by spectroscopic methods (1D and 2D NMR, MS). 相似文献
14.
Li‐Rong Sun Jian Yan Lu Lu Sheng‐Ji Pei Zhong‐Rong Li Lin Zhou Xian‐Min Zhang Ming‐Hua Qiu 《Helvetica chimica acta》2007,90(7):1313-1318
Cimicifine A ( 1 ), the first cycloartane triterpene alkaloid, was isolated from the rhizomes of Cimicifuga foetida, together with the known compound cimicifugoside H‐1 ( 2 ). Their chemical structures were established by extensive NMR and MS analyses and by comparison with literature. 相似文献
15.
One new sesquiterpenoid alkaloid, namely 3 beta,8 alpha-dihydroxy-13-pyrrolidine-4(15),10(14)-(1 alpha H,5 alpha H,6 beta H,11 beta H)-guaiadien-12,6-olide (1), together with two known guaiane-type sesquiternoids (2-3) was isolated from the aerial part of Acroptilon repens. The structure of 1 was established by spectroscopic methods, especially 2D NMR (HMQC, HMBC, and NOESY). Cytotoxic activity against tumor cell line was assessed for compounds 2-3, and found to show potent cytotoxic activities against tumor cell line P-388. 相似文献
16.
The 300 MHz 1H-NMR. spectrum of the alkaloid Roxburghine B is completely analysed. The coupling constant values give evidence for the configuration, which is revised to epi-allo: H(3β), H(15α), H(20α) and C(18β). 相似文献
17.
18.
Nunes FM Barros-Filho BA de Oliveira MC Andrade-Neto M de Mattos MC Mafezoli J Pirani JR 《Magnetic resonance in chemistry : MRC》2005,43(10):864-866
One- and two-dimensional NMR experiments were used for the unambiguous assignment of the (1)H and (13)C NMR chemical shifts of the furoquinoline alkaloid maculine (1) and the new furanocoumarin 3,8-dimethoxyfuro[3,2-g]coumarin (2). 相似文献
19.
Leyla Bitiş Sevda Süzgeç Ulaş Sözer Hasan Özçelik Josef Zapp Alexandra K. Kiemer Filiz Meriçli Ali H. Meriçli 《Helvetica chimica acta》2007,90(11):2217-2221
From the aerial parts of Delphinium buschianum Grossh ., collected in Turkey, a new diterpenoid alkaloid 1 , named budelphine, was isolated along with the known diterpenoid alkaloids karakoline ( 2 ), 18‐hydroxy‐14‐O‐methylgadesine ( 3 ), delsoline ( 4 ), lapaconidine ( 5 ), columbianine ( 6 ), 14‐benzoylneoline ( 7 ), and hetisine ( 9 ). The structure of 1 was established on the basis of 1H‐, 13C‐, DEPT, 1H,1H‐COSY, NOESY, HSQC, and HMBC NMR studies. 相似文献
20.
Shiqing Song Pan Liu Liying Wang Danna Li Huaying Fan Daquan Chen 《Natural product research》2020,34(18):2694-2697
AbstractNaucleoffieine H, a natural indole alkaloid, was isolated and identified from Nauclea officinalis Pierrc ex Pitard which is a traditional Chinese medicine used for the treatment of various diseases, such as cold, fever, bronchitis, pneumonia, acute tonsillitis, etc. In the present study, the effect of naucleoffieine H on the anti-inflammatory activities was investigated in LPS-induced RAW 264.7 macrophages. The results showed that naucleoffieine H significantly inhibited the release of nitric oxide (the level of nitrite as a stable biomarker of NO production) and tumor necrosis factor-α (TNF-α). Interesting, naucleoffieine H down-regulated the overexpression of inflammatory protein induced nitric oxide synthase (iNOS), but no effect on the expression cyclooxygenase-2 (COX-2) protein. In addition, this bioactive alkaloid suppressed enzymatic activity of iNOS activated by LPS. The above results indicated that naucleoffieine H suppress NO and TNF-α overproduction via block the iNOS pathway in LPS-induced RAW 264.7 macrophages. 相似文献