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1.
Fluorobicyclo[2,2,2]octanes as follows were made by fluorination with cobaltic fluoride :- 1H- and 2H- tridecafluoro- ; 1H,2H-, 1H,3H-, 2H,2H-, 2H,3H-, and 1H,4H- dodecafluoro-; 1H,2H,3H-, 1H,2H,4H-, and 1H,3H,3H- undecafluoro-; 2H,2H,3H,3H- decafluoro-. These afforded, by the appropriate dehydrofluorinations, dodecafluoro-; 1H- and 2H- undecafluoro-; 1H,2H-, 1H,3H-, and 1H,4H- decafluoro- bicyclo[2,2,2]oct-2-ene. Self-consistent nmr data confirmed all structures. 1H-Trideca- and 1H,4H-dodeca- fluorobicyclo[2,2,2]octanes possess acidic bridgehead hydrogens, which are reactive under basic conditions, and may be replaced by various functional groups. 1-Lithiotridecafluorobicyclo[2,2,2]octane, a remarkably stable perfluoroalkyl lithium derivative, survived many hours in refluxing ether, but slowly decomposed to 1- substituted undecafluorobicyclo[2,2,2]oct- 2-enes, via a transient intermediate, a bridgehead ‘olefin’ ‘violating’ Bredt's rule. 相似文献
2.
N-5-(1H-1,2,4-三唑基)-N'-芳甲酰基脲的合成与生物活性 总被引:5,自引:2,他引:5
以5-氨基-1H-1,2,4-三唑-3-羧酸与酰基异氰酸酯反应,合成了15个新的N- 5-(1H-1,2,4-三唑基)-N'-芳甲酰基脲,用核磁共振氢谱、红外光谱和元素分 析确证了其结构,并进行了室内生物活性测试。生测试验证明部分酰基脲类化合物 具有良好的植物生长调节活性,其中N-5(3-羧基-1,2,4-三唑基)-N'-o-氯苯甲 酰基脲、N-5-(3-羧基-1,2,4-三唑基)-N'-o-溴苯甲酰基脲和N-5-(3-羧基-1, 2,4-三唑基)-N'-p(或m)-甲基苯甲酰基脲具有优良的生长素活性。 相似文献
3.
T Kajimoto Y Imamura M Yamashita K Takahashi M Shibata T Nohara 《Chemical & pharmaceutical bulletin》1989,37(8):2212-2213
The proton and carbon-13 nuclear magnetic resonance signals of cytochalasin E (1) were assigned with the aid of 1H-1H, 1H-13C and 1H-13C long-range chemical shift correlation spectroscopy spectra, and the structure of the decomposition product (2) generated under neutral conditions was determined. 相似文献
4.
5.
Toshihide Baba Yuki Morikawa Norito Komatsu Toshiro Takahashi Hisashi Sugisawa Yoshio Ono 《Research on Chemical Intermediates》2000,26(1):13-20
The dynamic properties of protons in H-[Ga]-ZSM-5, H-[B]-ZSM-5 and H-[Al-B]-ZSM-5 were compared with that of protons in H-[Al]-ZSM-5
by temperature dependence of 1H MAS NMR in the range of 298 k and 473 K. The temperature dependence of the line width of 1H MAS NMR reveals that protons in H-[Ga]-ZSM-5 were more mobile than those in H-[Al]-ZSM-5 at temperature as low as 373 K.
The protons in H-[B]-ZSM-5 were not mobile at 473 K and fixed in the zeolite frame work as the bridging hydroxyl groups, ≡B-OH-Si≡.
The thermal motion of protons in ≡Al-OH-Si≡ was suppressed by introducing B3+ cations into the framework of H-[Al]-ZSM-5. 相似文献
6.
1,1,1-Kestopentaose是菊粉(Inulin)类中的一个葡果糖化合物(β-D-果糖-(2→1)-β-D-果糖(2→1)-β-D-果糖-(2→1)-α→D-葡萄糖)本文采用各种2D-NMR技术,包括H-HCOSYF1-去偶H-HCOSY HMQC和HMBC等,归属了它的H和C的谱线,并得到了有关质子间的偶合常数,为进一步分析其在溶液中的三维空间结构打下了基础。 相似文献
7.
Parthiban P Balasubramanian S Aridoss G Kabilan S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(1):11-24
Variously substituted 2,6-diarylpiperidin-4-one O-benzyloximes were synthesized by the direct condensation of the corresponding 2,6-diarylpiperidin-4-ones with O-benzylhydroxylamine hydrochloride. All the synthesized compounds are characterized by IR, Mass and NMR spectral studies. NMR spectral assignments are made unambiguously by their one-dimensional (1H NMR and 13C NMR) and two-dimensional (1H-1H COSY, NOESY, HSQC and HMBC) NMR spectra. All the synthesized compounds are resulted as single isomer, i.e., exclusively E isomer (9-14). The conformational preference of 2,6-diarylpiperidin-4-one oxime ethers with and without alkyl substituents at C-3 and C-5 has also been discussed using the spectral studies. The observed chemical shifts and coupling constants suggest that compounds 8-13 adopt normal chair conformation with equatorial orientation of all the substituents while compound 14 contributes significant boat conformation along with the predominant chair conformation in solution. The effect of oximination on ring carbons, their associated protons, alkyl substituents and ipso carbons are studied. Every proton in the piperidone ring of the oxime ether is observed as distinct signal due to oximination. The order of chemical shift magnitude in compound 8 is H-2a>H-6a>H-5e>H-3e>H-3a>H-5a. For 9-12, the order is H-6a>H-5e>H-2a>H-3a>H-5a, for 13, H-6a>H-2a>H-5e>H-3a>H-5a and for 14, the order is H-2a>H-6a>H-5e>H-3a>H-5a while the 13C chemical shift magnitude for 8-14 due to oximination is C-2>C-6>C-3>C-5. 相似文献
8.
SONGHong-rui WANGFei LIJian ZHANGShou-fang 《高等学校化学研究》2005,21(4):460-462
The three title compounds were prepared from 2-phenylaminomethyl-3H-1,2-dihydro-l-pyrrolizinols via an intramolecular Friedel-Crafts reaction. 2-Phenylaminomethyl-3H-1,2-dihydro-1-pyrrolizinols were prepared from 2-phenyl-aminomethyl-3H-1,2-dihydro-1-pyrrolizinones via reduction. The heterocyclic ring system of pyrrolizino[2,1-c] quinoline has not been found in literature. 相似文献
9.
Forsythiasuspensa(ThUnb.)VahlhasbeenusedintradihonalChinesemedicineforanhiallammatoryandamibacterialpmposes.AnUInberofcompoundssuchasforsythiaside,phillygeninrengyoletc.haVebeenidentifiedl-#fromthefactsofmisplat.AsPartofourstudyontheachveprinciplesoftradihonalChinesemedicine,wereinvestigatCdthechemicalconstitllentsofRsuspensa.heartycompoundshavebeenisolatCdfromthisspecies.ThispaperdescribesthestrUcturalelucidahonofthreenewcompoundsfsuspenolicacid(1),forSythensideA(2),andforsythensideB(3)… 相似文献
10.
Chun DAN Rui WANG Shu Lin PENG Bing Ru BAI Li Sheng DING 《中国化学快报》2006,17(3):347-350
The rhizomes of Cimicifuga racemosa has been used as anti-inflammatory, analgesic and antipyretic agents in traditional Chinese medicine1. Some cimicifugosides belonging to highly oxygenated 9,19-cyclolanostane triterpene glycosides, in addition to cinnam… 相似文献
11.
Dzygiel A Rzeszotarska B Masiukiewicz E Cmoch P Kamieński B 《Chemical & pharmaceutical bulletin》2004,52(2):192-198
Methyl 5-amino-1H-[1,2,4]triazole-3-carboxylate hydrochloride (1). and free ester (2). were obtained and 2 was reacted with Ac(2)O to give the acetylated products 3-6. Compounds 1-6 were studied using HPLC, GC-MS, FTIR and multinuclear NMR spectroscopy, including the cross-polarisation magic angle spinning (CPMAS) technique. The results of the acetylation of 2 were compared to those of the acetylation of 5-amino-1H-[1,2,4]triazole, and for 2 a significant decrease in the susceptibility to acetylation was found. The reaction of 2 with Ac(2)O at 20 degrees C, regardless of the amount and the concentration of the latter, including neat Ac(2)O, proceeds fully regioselectively and leads to one product: methyl 1-acetyl-5-amino-1H-[1,2,4]triazole-3-carboxylate (3). In sharp contrast to 5-amino-1H-[1,2,4]triazole, neither an additional monoacetylated isomer, whether annular or exocyclic, nor any diacetylated derivative could be detected. The diacetylation of 2 requires the process to be carried out in neat boiling Ac(2)O and, as in the case of 5-amino-1H-[1,2,4]triazole, gives two diacetylated isomers. These are methyl 1-acetyl-3-(acetylamino)-1H-[1,2,4]triazole-5-carboxylate (4) and 1-acetyl-5-(acetylamino)-1H-[1,2,4]triazole-3-carboxylate (5). Hypothetical pathways of their formation have been suggested. A mixture of 4 and 5 upon hydrolysis of the ring acetyl group gives the monoacetylated derivative methyl 5-(acetylamino)-1H-[1,2,4]triazole-3-carboxylate (6). The spectroscopic, structural and conformational characteristics of compounds 1-6 have been given and methods for their preparation have been provided. 相似文献
12.
Nuclear magnetic resonance (NMR) spectroscopic analysis of metabonome/metabolome has widespread applications in biomedical science researches. However, most of NMR resonances for urinary metabolites remain to be fully assigned. In the present study, human urine samples from two healthy volunteers were pre-treated with C18 solid-phase extraction and the resultant 5 sub-fractions were subjected to one- and two-dimensional NMR studies, including 1H J-Resolved, 1H-1H COSY, 1H-1H TOCSY, 1H-13C HSQC, and HMBC 2D NMR. More than 70 low molecular weight metabolites were identified, and complete assignments of 1H and 13C resonances including many complex coupled spin systems were obtained. 相似文献
13.
Dupuy N Barbry D Bria M Marquis S Vrielynck L Kister J 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(6):1051-1057
Proton nuclear magnetic resonance spectroscopy ((1)H NMR), which has become an important tool for the study "in situ" of beta-cyclodextrin (beta-CD) complexes, was used to study and structurally characterize the inclusion complexes formed between beta-CD and isoproturon, fenuron, monuron and diuron. The high variation of the chemical shifts from the proton located inside the cavity (H-3, H-5 and H-6) coupled with the non variation of the one located outer sphere of the beta-CD (H-1, H-2 and H-4) provided clear evidence of the inclusion phenomena. Two-dimensional rotating frame Overhauser effect spectroscopy (ROESY) experiments were carried out to further support the proposed inclusion mode. 相似文献
14.
15.
Tetrazolo[1,5-a]pyridines/2-azidopyridines 1 undergo photochemical nitrogen elimination and ring expansion to 1,3-diazacyclohepta-1,2,4,6-tetraenes 3, which react with alcohols to afford 2-alkoxy-1H-1,3-diazepines 4 (5), with secondary amines to 2-dialkylamino-5H-1,3-diazepines 16, sometimes via isolable 2-dialkylamino-1H-1,3-diazepines 15, and with water to 1,3-diazepin-2-ones 19. The latter are also obtained by elimination of isobutene or propene from 2-tert-butoxy- or 2-isopropoxy-1H-1,3-diazepines 4 or 5. 1,3-Diazepin-2-one 22B and 1,3-diazepin-4-one 24 were obtained from hydrolysis of the corresponding 4-chlorodiazepines. Diazepinones 19 undergo photochemical ring closure to diazabicycloheptenones 25 in high yields. The 2-alkoxy-1H-1,3-diazepines 4 and 5 interconvert by rapid proton exchange between positions N1 and N3. The free energies of activation for the proton exchange were measured by the Forsén-Hoffman method as DeltaG([double dagger])298= 16.2 +/- 0.6 kcal mol(-1) as an average for 4a-c in CD2Cl2, acetone-d6, and methanol-d4, and 14.1 +/- 0.6 kcal mol(-1) for in 4c acetone/D2O. The structures of 2-methoxy-5,6-bis(trifluoromethyl)-1H-1,3-diazepine 4k, 1,2-dihydro-4-diethylamino-5H-1,3-diazepin-2-one 22bB, and diazabicycloheptanone were 26 determined by X-ray crystallography. The former represents the first reported X-ray crystal structure of any monocyclic N-unsubstituted 1H-azepine. 相似文献
16.
采用Dmol3程序中基于密度泛函理论(DFT)的广义梯度方法(GGA)和BLYP方法以及DND基组, 研究了丝光沸石H-[M']MOR、Cu-[M']MOR和Ag-[M']MOR(M'=B, Al, Ga, Fe)结构及其对NH3分子的吸附, 获得了吸附平衡构型和吸附能. NH3分子在H-[M']MOR中的吸附主要是通过NH3分子中氮原子上的孤对电子与质子酸位作用, NH3分子在H-[Al]MOR、H-[Ga]MOR和H-[Fe]MOR上发生化学吸附, 而在H-[B]MOR上发生物理吸附, 这与文献结果相符. NH3分子与Cu-[M']MOR 和Ag-[M']MOR分子筛之间主要通过氮上的孤对电子和平衡离子(Cu+和Ag+)的s空轨道间配位作用而发生化学吸附. 吸附能数据表明, 在H-[M']MOR、Cu-[M']MOR 和Ag-[M']MOR中, A1原子进入骨架导致H-[A1]MOR、Cu-[A1]MOR和Ag-[A1]MOR的酸强度最强; 对于同一种原子取代的丝光沸石, 其酸强度次序为: Cu-[M']MOR > Ag-[M']MOR > H-[M']MOR. 此外, 还对吸附前后的沸石中平衡离子(H+、Cu+和Ag+)及NH3分子的Mulliken电荷集居数作了研究和分析. 相似文献
17.
ZHOU Cheng-He WU Jun YUAN Yong BAI Xue Juan F.Miravet M.Isabel Burguete Santiago V.Luis 《有机化学》2004,24(Z1):377
A novel tetra-histidine cyclopeptide was prepared through multi-step reactions from histidine and naphthalene diamine (Scheme 1). All new compounds were characterized by 1H, 13C, 1H-15N and 1H-13C HETCOR spectra. 相似文献
18.
Yamada-Hada J Hada N Aoki K Yamamoto K Takeda T 《Chemical & pharmaceutical bulletin》2004,52(4):473-476
The sugar-inositol portion of the novel glycosylinositol-phosphoceramides, ZGL1 and ZGL2, from the filamentus fungi, Acremonium sp., were elucidated by a combination of NMR techniques including (1)H-(1)H (COSY and HOHAHA) and (1)H-(13)C (HMQC and HMBC) spectroscopy. Further, examination of the (1)H-(31)P HMQC spectrum showed connectivity of inositol and ceramide through phosphate. 相似文献
19.
Abou-Douh AM 《Chemical & pharmaceutical bulletin》2008,56(11):1535-1545
In bioassay-guided searches for novel bioactive natural products from higher plants of the Egyptian flora, two new eudesmane sesquiterpene derivatives, 3alpha-hydroxyilicic acid methyl ester (1) and 2alpha-hydroxy-4-epi-ilicic acid (2), together with 11 known sesquiterpenes were isolated from bioactive fractions of the active epigeal parts extracts of Dittrichia graveolens (L.) GREUTER (Asteraceae) growing in the coastal regions of northwestern Egypt. Four other known sesquiterpene lactones with different carbon skeletons, named 2alpha-hydroxy-2R-xanthalongin (8), 4-epi-isoinuviscolide (9), 8-epi-helenalin (10), and bigelovin (11), were also isolated for the first time from the same source. The stereochemical structures of the isolated compounds were elucidated on the basis of physical and spectroscopic methods including UV, IR, 1H-, 13C-NMR, distortionless enhancement by polarization transfer, 2D NMR, 1H-1H correlation spectroscopy, 1H-13C heteronuclear single-quantum coherence, 1H-13C heteronuclear multiple-bond connectivity, 1H-1H nuclear Overhauser effect spectroscopy experiments, and high-resolution mass spectrometry, as well as some chemical transformations. The antimicrobial, antiinflammatory, and antipyretic activities of D. graveolens extracts and chromatographic fractions were carried out and the various bioactivities of our findings are discussed. 相似文献
20.
da Silva Júnior EN de Souza MC Pinto AV Pinto Mdo C Nogueira CM Ferreira VF Azeredo RB 《Magnetic resonance in chemistry : MRC》2008,46(12):1158-1162
Six new nor-beta-lapachones have been synthesized from reaction of 3-bromo-nor-beta-lapachone with arylamines. These derivatives have potent anticancer properties against several cell lines. Here, we report complete unambiguous assignments of (1)H and (13)C chemical shifts of the new compounds. The assignments were made using a combination of one- and two-dimensional NMR techniques ((1)H, (13)C, (1)H-(1)H COSY, (1)H-(13)C HSQC, and (1)H-(13)C HMBC). 相似文献