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1.
李英和  陈迪华 《化学学报》1994,52(2):204-208
从短距乌头(Aconitum brevicalcaratum Diels)的根中分得六个二萜生物碱成分,其中三个为新成分,即短距乌碱甲(acobretine A,1),短距乌碱乙(acobretine B,2)和短距乌碱丙(acobretine C,3).另三个为已知成分:花葶乌头宁(scaconine,4),花葶乌头碱(scaconitine,5)和N-脱乙酰花葶乌头碱(N-deacetylscaconitine,6).经IR,MS,^1H NMR,^1^3C NMR测定和化学方法确定可1~3的结构  相似文献   

2.
细花百部碱的结构   总被引:2,自引:0,他引:2  
从海南岛产野生细花百部(Stemona parciflora Wright, C.H.)的根部分得一新生物碱-细花百部碱(parviatemonine), 根据MS, ^1H NMR去偶, ^1H-^1HCOSY , NOESY, ^1^3C-^1H异核相关谱, ^1^3C NMR及^1H NMR 宽峰效应等技术推定了结构, 在百部类生物碱中首次归属了质子和碳原子的NMR信号, 该结构业经X单晶衍射法证实。  相似文献   

3.
小果博落回对照物质及其核磁共振氢谱指纹图的创建   总被引:8,自引:0,他引:8  
秦海林  王鹏  李志宏  刘欣  贺文义 《分析化学》2004,32(9):1165-1170
采用规范化的程序获取6个不同来源小果博落回样品的对照物质(CSPD)及其^1H NMR图谱;从小果博落回CSPD中分得6个单体成分,其结构分别被鉴定为二氢血根碱(1)、二氢白屈菜红碱(2)、6-甲氧基二氢血根碱(3)、6-甲氧基二氢白屈菜红碱(4)、齐墩果酸(5)和原阿片碱(6)。通过各单体化合物的^1H NMR图谱与CSPD的^1H NMR图谱的对比研究,实现了小果博落回的^1H NMR指纹图的解析。研究结果表明:6个不同来源的小果博落回样品,其^1H NMR指纹图有很好的重现性和高度的特征性,并主要显示以上生物碱类成分的特征共振信号,可做为其基源鉴定的参考。  相似文献   

4.
从赣皖乌头(Aconitum finetianum Hand-Mazz)中又分得五个生物碱, 其中三个为新的二萜类生物碱, 分别命名为去氧刺乌头碱(deoxylappaconitine), 赣乌新碱(neofinaconitine)和异刺乌状碱(isolappaconitine), 经IR、MS、^1H和^1^3C NMR推定了它们的化学结构, 另两个为已知生物碱ajacine和inuline.  相似文献   

5.
从海南岛产野生百部(Stemona parviflora Wright C.H.)的根部又分得三个微量生物碱成份, 其中羟基百部叶碱(oxystemofoline)(1)和甲氧代百部叶碱(methyloxystemofoline)(2)为新生物碱成份。经IR, MS, ^1H和^1^3C NMR, NOE, 2D-同核及异核相关谱以及远程偶合相关谱推定了它们的结构, 并首次归属了它们的^1^3CNMR信号。  相似文献   

6.
林文翰  徐任生  钟琼芯 《化学学报》1991,49(10):1034-1037
从海南岛产野生百部(Stemona parviflora Wright C.H.)的根部又分得三个微量生物碱成份, 其中羟基百部叶碱(oxystemofoline)(1)和甲氧代百部叶碱(methyloxystemofoline)(2)为新生物碱成份。经IR, MS, ^1H和^1^3C NMR, NOE, 2D-同核及异核相关谱以及远程偶合相关谱推定了它们的结构, 并首次归属了它们的^1^3CNMR信号。  相似文献   

7.
百部生物碱的化学研究 I. 细花百部新生物碱   总被引:1,自引:0,他引:1  
从海南岛产野生百部, 细花百部(Stemona parviflora Wright C.H.)的根部又分得三个新生物碱, 分别命名为细化百部酰胺(parvistemoamide)(1), 细花百部次碱(parvistemolone)(2)和脱氢细花百部碱(didehydroparvistemonine)(3)。经IR, MS,^1H和^1^3C NMR、NOE差谱, 2D-同核及异核相关谱等技术推定了结构。同时归属了它们的^1H和^1^3C NMR信号。  相似文献   

8.
从海南岛产野生百部, 细花百部(Stemona parviflora Wright C.H.)的根部又分得三个新生物碱, 分别命名为细化百部酰胺(parvistemoamide)(1), 细花百部次碱(parvistemolone)(2)和脱氢细花百部碱(didehydroparvistemonine)(3)。经IR, MS,^1H和^1^3C NMR、NOE差谱, 2D-同核及异核相关谱等技术推定了结构。同时归属了它们的^1H和^1^3C NMR信号。  相似文献   

9.
从翠雀花根的乙醇提取物中分得两个新的C~2二萜生物碱:翠雀花定(1)和乙酰翠雀花定(2)经谱图分析(IR, ^1H和^13C NMR, )推定了它们的结构。迄今报告的C~20二萜生物碱中, 1和2在结构上是具有含氧了取代基最多的两例药理试验表明,2有镇痛作用。  相似文献   

10.
远程二维NMR用于马尾杉碱M的结构测定   总被引:1,自引:0,他引:1  
马尾杉碱是一种从华南马尾杉(新品科植物)中分得的新的生物碱。其分子式为C17H20N2O3, 通过紫外, 红外, ^1H和^1^3C NMR谱图分析发现其结构与最近文献报导的福定碱或石杉碱相类似, 本文还采用普通和远程的^1^3C-^1H COSY二维NMR新技术进行了研究, 所得结果与上述分析相符。  相似文献   

11.
秦岭龙胆的化学成分   总被引:6,自引:0,他引:6  
周乐  王宁  苗芳  赵海双  田鹏 《有机化学》2004,24(10):1249-1252
从秦岭龙胆(Gentiana apiata N.E.Br.)全草的乙醇提取物中分离得到4个化合物,通过波谱分析分别鉴定为异荭草甙(isoorientin),龙胆苦甙(gentiopicroside),asystasioside A和蔗糖(D-sucrose).采用二维NMR分析,确定了asystasioside A的立体结构.以上化合物均为首次从该植物中发现.  相似文献   

12.
A series of novel eight-membered heterocycles containing 1,3 and 1,5 phosphorus arrangements were synthesized. The 1,5-diphosphatetraazacyclooctatetraenes were obtained from the interaction of perfluoroalkyletheramidines and trichlorophosphoranes; the 1,3-isomers were prepared from perfluoroalkyletherimidoylamidines and imido-tetraphenyl-diphosphinic acid trichloride. The two series of cyclooctatetraenes exhibited infrared spectral absorptions characteristic for the given positional arrangement. However, electron impact fragmentation patterns of the two ring systems were closely comparable.  相似文献   

13.
A variety of copolydisulfides have been synthesized in high yields by the fragmentation polymerization of bis(sulfenyl thiocarbonates) with dithiols in the presence of triethylamine. The structures of the copolymers were investigated by x-ray and NMR studies. Alkylene–arylene copolydisulfides were alternating. Alkylene–arylene copolymers derived from arylene dithiols were alternating, and those prepared from alkylene dithiols were generally random. It was concluded that the present procedure makes it possible to prepare various kinds of alternating copolydisulfides by using appropriate combinations of a bis(sulfenyl thiocarbonate) and a dithiol.  相似文献   

14.
Two new C-glucoside flavonoids,namely 8-C-β-D-(2″-O-acetyl) glucofuranosyl apigenin and 3″-O-acetylvitexin, were isolated from beaves of Crataegus pinnatifida Bge. var. major N.E.Br.Their structures were elucidated by the spectroscopic means and chemical evidence.  相似文献   

15.
2-tert-Butyl-4-methyl- and 2-methyl-4-tert-butylbenzopyrylium salts, as well as the sulfitr analog of the latter, were synthesized. Polymethine dyes with symmetrical and unsymmetrical structures were obtained from these salts. The factors that affect the color are analyzed.See [1] for Communication 28.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 339–344, March, 1992.  相似文献   

16.
Aristoserratine, a New Indole Alkaloid from Aristotelia serrata W.R.B. OLIVER and from A. peduncularis (LABILL .) HOOK . F. The new indole alkaloid aristoserratine (2) has been isolated from Aristotelia. Its structure and absolute configuration were elucidated on the basis of spectroscopic data.  相似文献   

17.
The synthesis and characterization of two novel cyclic siloxanes, diacetoxydiethyltetramethylcyclotetrasiloxane and diacetoxytriethylpentamethylcyclopentasiloxane, and cyclolinear polymers synthesized from these monomers are presented. The cyclic siloxanes were synthesized from tetramethylcyclotetrasiloxane and pentamethylcyclopentasiloxane, respectively, by acetylation followed by ethylation. The cyclic monomers were characterized with 1H NMR spectroscopy. Subsequently, the cyclic siloxanes were self‐condensed into cyclolinear polysiloxanes and cocondensed (extended) with silanol‐terminated polydimethylsiloxane into high‐molecular‐weight polymers containing cyclic units withlinearpolydimethylsiloxane spacers (extended cyclolinear polysiloxanes). The molecular weights of both the cyclolinear polysiloxanes and extended cyclolinear polysiloxanes were determined. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4039?4052, 2006  相似文献   

18.
Two Legionella-like organisms were isolated from cooling-tower water samples in Czechoslovakia. They were presumptively identified as legionellae by their growth on buffered charcoal-yeast extract agar (BCYE) containing L-cysteine and their absence of growth on BCYE without L-cysteine. Both strains contained predominantly branch-chained cellular fatty acids and were therefore definitively placed in the genus Legionella. They were serologically distinct from other described Legionella species and were shown by DNA studies to constitute two new Legionella species, Legionella moravica (type strain 316-36; ATCC 43877) and Legionella brunensis (type strain 441-1; ATCC 43878).  相似文献   

19.
The volatile monoterpenic and norisoprenoidic compounds released by glycosidase enzyme hydrolysis of C18 reversed-phase isolates from the juice of Vitis vinifera L. cv. Melon B. have been qualitatively and quantitatively determined using GC-MS and GC-FID. The components analyzed were broadly similar to those previously reported for other varieties but the level of bound p-menth-1-en-7,8-diol was higher in this cultivar. Then the monoterpenic and norisoprenoidic volatiles released from the same glycosidic extracts under mild acid conditions, mimicking wine aging conditions, have been analyzed using GC-Olfactometry and GC-MS. The most odorous compounds detected were p-cymene, terpinen-4-ol, cis- and trans-vitispiranes, 1,6,6-trimethyl-1,2-dihydronaphtalene (TDN), beta-damascenone and riesling acetal. To assess their potential levels in corresponding wines after ageing, most of these odorants were generated by harsh acid hydrolysis from the precursors extracts and quantitatively determined using SPME and GC-MS/MS. For the development and application of this analysis, the odorants not commercialy available were synthesized. The total amounts of norisoprenoidic odorants generated by acid hydrolysis of the glycosidic extracts were shown to be proportional to the total amounts of these precursors.  相似文献   

20.
Partially ordered polyarnide-hydrazides were produced by the poly condensation of diacid chlorides with aminobenz-hydrazides, the order that results being a consequence of the considerably more rapid reaction of a diacid chloride with the hydrazide group in competition with the aromatic amine group of the aminobenzhydrazide. Fibers were produced from a series of such polymers containing from 50 mole % meta-oriented phenylene rings to 100 mole % para-oriented ones. Fiber from the wholly para-oriented type of polymer exhibited very high strength and modulus: 12.5 and 468 g/den, respectively, at 4.3% elongation-to-break. Although the crystallinity and density observed for hot-drawn fibers of partially ordered completely para-oriented polyarnide-hydrazides were comparable to the crystallinity and density of fibers of the isomeric wholly ordered polymer, the partially ordered polymers were more readily spun to the ultra-high strength and high modulus type fibers, probably because their greater solubility made them easier to spin.  相似文献   

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