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HMBC
Terms modified by HMBC Selected AbstractsSecondary Metabolites of Phomopsis sp.EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 18 2009XZ-2, an Endophytic Fungus from Camptothecaacuminate Abstract Eleven new metabolites, including nine lovastatin analogues [oblongolides N,V (1,2 and 5,11), which were defined as naphthalene-type fungal polyketides], one linear furanopolyketide (13) and a monoterpene named dihydroxysabinane (14), together with four known compounds including oblongolides B (3) and C (4), one linear furanopolyketide (12) and the sesterterpene terpestacin (15), were isolated from the endophytic fungal strain Phomopsis sp. XZ-26 of Camptotheca acuminate. Their structures were elucidated by spectroscopic analyses including HR-ESI-MS, 1H and 13C NMR, 2D NMR (HMQC, HMBC, 1H- 1H COSY and NOESY), and X-ray single-crystal analysis. The antimicrobial activities of 1,5, 8, 10 and 13,15 were evaluated, but none showed a substantial effect. Additionally, a hypothetical biosynthetic pathway for oblongolides was proposed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Essential oils and a novel polyacetylene from Eryngium yuccifolium Michaux. (Apiaceae),FLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2006Nahla Ayoub Abstract The essential oils of Eryngium yuccifolium Michaux. (Apiaceae) were isolated from the leaves, stalks and roots by hydrodistillation. Analysis of the oils by GC and GC,MS revealed that the leaves oil contained 49 compounds, of which germacrene D (18.3%), terpinolene (17.8%), bicyclogermacrene (8.8%), , -pinene (7.6%), ß-caryophyllene (6.2%) and falcarinol (9.6%) were found to be the major constituents. In addition, 40 compounds were identified from the stalk oil, among which, germacrene D (38.4%), , -amorphene (12.2%), bicyclogermacrene (10.1%), bicyclosesquiphellandrene (3.4%) and falcarinol (3.2%) were the major components. The roots oil was found to contain 25 compounds, of which, terpinolene (25.8%), trans - , -bergamotene (18.6%) and the benzaldehyde 2,3,6-trimethylbenzaldehyde (13.9%), were the major constituents. Yuccifolol (nonadeca-1,11-diene-4,6,8-triyne-3,10-diol), a novel polyacetylene, was isolated and identified from the hexane:ether extract of the aerial parts, together with the known polyacetylenes, falcarinone [heptadeca-1,9-(Z)-dien-4,6-diyn-3-one], falcarinol (heptadeca-1,9-dien-4,6-diyn-3-ol) and heptadeca-1,8-diene-4,6-diyne-3,9-diol. The chemical structures of these constituents were established by NMR (DEPT, COSY, HMQC and HMBC) as well as HRESI,MS analysis. Copyright © 2006 John Wiley & Sons, Ltd. [source] New Chemical Constituents from Borreria verticillata (Rubiaceae)HELVETICA CHIMICA ACTA, Issue 9 2010Vinicius F. Moreira Abstract A phytochemical study on Borreria verticillata has led to the isolation of two novel simple indole alkaloids, 6-methoxy-4-(3-methylbut-2-en-1-yl)-1H -indole, named verticillatine A (1), and 1-(1H -indol-6-yl)-3-methylbutan-1-one, named verticillatine B (2), one new iridoid, 6,- O -(2-glyceryl)scandoside methyl ester (3), with the glycerol unit linked to a glucose unit, and two known ones, asperuloside (4) and scandoside methyl ester (5). The structures of these compounds were elucidated on the basis of spectroscopic-data analyses, mainly 1H- and 13C-NMR, including 2D experiments (1H,1H-COSY, NOESY, HMBC, and HMQC), and HR-ESI-MS. [source] Two New Secolignans from the Roots of Urtica fissa E. PritzHELVETICA CHIMICA ACTA, Issue 5 2009Bao-Quan Ji Abstract Two new secolignans, {(3S,4S)-4-[bis(4-hydroxy-3-methoxyphenyl)methyl]-2-oxotetrahydrofuran-3-yl}methyl , - D -glucopyranoside (1) and its stereoisomer {(3S,4R)-4-[bis(4-hydroxy-3-methoxyphenyl)methyl]-2-oxotetrahydrofuran-3-yl}methyl , - D -glucopyranoside (2), have been isolated from the roots of Urtica fissa E. Pritz. Their structures were determined based on spectroscopic methods (HR-MS, 1D- and 2D-NMR, HMBC, HSQC, and NOESY). [source] Three New Arylnaphthalide Lignans from the Aerial Parts of Bupleurum marginatumWall. ex DC.HELVETICA CHIMICA ACTA, Issue 12 2008Ying Liu Abstract Three new arylnaphthalide lignans, 5-(4-hydroxy-3-methoxyphenyl)furo[3,,4,:,6,7]naphtho[2,3- d]-1,3-dioxol-6(8H)-one (1), 10-(4-hydroxy-3-methoxyphenyl)furo[3,,4,:,6,7]naphtho[1,2- d]-1,3-dioxol-9(7H)-one (2), and 10-(3,4-dimethoxyphenyl)-6-hydroxyfuro[3,,4,:,6,7]naphtho[1,2- d]-1,3-dioxol-9(7H)-one (3), together with two known ones, chinensin (4) and isodiphyllin (5), were isolated from the aerial parts of Bupleurum marginatumWall. ex DC. The structures of the three new lignans were established by means of NMR spectroscopic studies, including HQSC, HMBC, and ROESY. [source] Two New Eremophilane-Type Sesquiterpenoids from the Rhizomes of Ligularia veitchiana (Hemsl.) GreenmHELVETICA CHIMICA ACTA, Issue 9 2008Cai-Fang Wang Abstract Two new eremophilane-type sesquiterpenoids eremophil-6-en-11-ol (1) and (7,,9,,10,)-9,10-epoxy-eremophilan-11-ol (2), together with a known eremophilane-type (6,,8,)-6,8-dihydroxyeremophil-7(11)-en-12-oic acid 12,8-lactone (3) were isolated from the rhizomes of Ligularia veitchiana. The structures of 1 and 2 were established by spectral analysis including 1H- and 13C-NMR, HSQC, HMBC, and HR-ESI-MS data. The compounds 1 and 3 were assessed against lung-cancer (A549) and stomach-cancer (BCG823) cell lines by the MTT method. The results showed that 1 exhibited significant inhibiting activities on the growth of these cancer cells with IC50 values between 1,100,,g/ml, whereas compound 3 had no effect on the same cell lines. [source] Three New Lanostane Triterpenoids, Inonotsutriols A, B, and C, from Inonotus obliquusHELVETICA CHIMICA ACTA, Issue 8 2008Sayaka Taji Abstract Three new lanostane-type triterpenoids, inonotsutriols A (1), B (2), and C (3) were isolated from the sclerotia of Inonotus obliquus (Pers.: Fr.) (Japanese name: kabanoanatake; Russian name: chaga). Their structures were determined to be (3,,21R,24S)-21,24-cyclolanost-8-ene-3,21,25-triol (1), (3,,21R,24R)-21,24-cyclolanost-8-ene-3,21,25-triol (2), and (3,,21R,24S)-21,24-cyclolanosta-7,9(11)-diene-3,21,25-triol (3) on the basis of NMR spectroscopy including 1D and 2D experiments (1H,1H-COSY, NOESY, HMQC, and HMBC) and EI-MS. [source] New Sesquiterpenoids from Ligularia duciformisHELVETICA CHIMICA ACTA, Issue 6 2008Wen-Shu Wang Abstract From the whole plants of Ligularia duciformis, four new sesquiterpenoids, 3, -acetoxy-6, -methoxyeremophila-7(11),9(10)-dien-12,8, -olide (1), 3, -acetoxy-8, -hydroxy-6, -methoxyeremophila-7(11),9(10)-dien-12,8, -olide (2), 3, -acetoxy-10, -hydroxy-6,,8, -dimethoxyeremophil-7(11)-en-12,8, -olide (3), and 3, -acetoxy-6,,8,,10, -trihydroxyeremophil-7(11)-en-12,8, -olide (4) were isolated. Their structures were established by high-field NMR techniques (1H,1H-COSY, 13C-APT, HMQC, HMBC, and NOESY) and HR-ESI-MS analysis, together with comparison of the spectroscopic data with those of structurally related compounds. In addition, the cytotoxicity of the new compounds against human hepatic cancer cells Bel-7402, human pneumonic cancer cells A-549, and human colonic cancer cells HCT-8 were evaluated, the new compounds showed no cytotoxicity against the three tumor cells (all IC50 values >200,,M). [source] Phenylpropanoid-Substituted Catechins and Epicatechins from Smilax chinaHELVETICA CHIMICA ACTA, Issue 9 2007Hui-Lian Huang Abstract The four new phenylpropanoid-substituted catechins 1, 3, and 4 and 3-epicatechin (2), together with seven analogues, were isolated from the AcOEt extract of Smilax china L. (catechin=(2R,3S)-2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H -2-benzopyran-3,5,7-triol). Their structures were determined by means of spectroscopic analyses, including HR-MS, IR, 1H- and 13C-NMR, and 2D experiments (COSY, HSQC, and HMBC), and comparison with known related compounds. [source] Triterpene Esters Isolated from Leaves of Maytenus salicifoliaReissekHELVETICA CHIMICA ACTA, Issue 4 2007Miranda, Rodrigues, Roqueline, Silva de Abstract The triterpene ester (3,)-olean-18-en-3-yl stearate (1), together with (3,)-urs-12-en-3-yl stearate (2), and (3,)-lup-20(29)-en-3-yl stearate (3) were isolated from leaves of Maytenus salicifoliaReissek (Celastraceae). The structure of 1, a new compound, including its configuration, was established by 1H, 13C, and DEPT-135 NMR data, including 2D experiments (HSQC, HMBC, COSY, and NOESY). The molecular mass (692 Da) was confirmed by gas chromatography coupled with mass spectrometry (CG/MS). [source] Isolation and Characterization of New Bitter Diterpenoids from the Basidiomycete Sarcodon scabrosusHELVETICA CHIMICA ACTA, Issue 11 2004Bing-Ji Ma The novel cyathane-type diterpenoids scabronine G and H (1 and 2, resp.) were isolated from the fruiting bodies of the basidiomycete Sarcodon scabrosus together with four known compounds, allocyathin B2 (3), sarcodonin A (4), sarcodonin G (5), and scabronine F (6). Their structures were determined by spectroscopic means, including 2D-NMR (HMBC, HMQC, ROESY, 1H,1H-COSY). [source] NMR Conformational Analysis and Theoretical Calculations for 2-Aryl- 1,3-dihydroxy-4,4,5,5-tetramethylimidazolidinesHELVETICA CHIMICA ACTA, Issue 2 2004Antônio Conformational studies of 1,3-dihydroxy-4,4,5,5-tetramethyl-2-(pyridin-1-yl)imidazolidine (1a) and 1,3-dihydroxy-4,4,5,5-tetramethyl-2-(pyridin-3-yl)imidazolidine (1b), carried out by using 1D 1H- and 13C-NMR and 2D HMQC, HMBC, and NOESY experiments and with the aid of theoretical calculations, indicate that the OH groups are trans to the pyridinyl substituent. Because the two 1H-NMR signals of the Me groups are distinguishable and do not change between 290 and 380,K, it is proposed that 1a and 1b have each only one conformation in this temperature range. This behavior was not found with 1,3-dihydroxy-4,4,5,5-tetramethyl-2-(pyridin-2-yl)imidazolidine (1c) because its Me 1H-NMR signals cross over at 300,K. Hence, more than one conformation must be present, beyond those produced by simple inversions. Theoretical calculations including temperature and solvent effects were performed to provide further information on the conformational analysis and to help to assign the NMR data. The combination of NMR measurements and quantum-chemical calculations is shown to be a very promising strategy for conformational analysis studies in solution. [source] m/p -Cresol,based t -BOC protected alternating "high ortho" copolymer as a possible e-beam resist: Characterization using multidimensional NMR spectroscopy,JOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2009Maneesh Sharma Abstract Synthesis of a m/p -cresol,based novolac resin and its subsequent esterification using di- tert -butyl dicarbonate (t -BOC) is described. The product has been characterized using techniques of FTIR spectroscopy, one dimensional 1H NMR, 13C NMR, and DEPT-135 spectra. Two dimensional NMR experiments like, COSY, HSQC, and HMBC have been used for exhaustive probing of the microstructural details of the derivatized copolymer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] Synthesis, structure and some reactions of 4a',5,,6,,7,,8,,8a'-hexahydro-4,H -spiro[cyclohexane-1,9,-[1,2,4]triazolo[5,1- b]-quinazolines]JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2008Victor M. Chernyshev 2,-Substituted 5,,6,,7,,8,-tetrahydro-4,H -spiro[cyclohexane-1,9,-[1,2,4]triazolo[5,1- b]quinazolines] 3a-d were synthesized by condensation of 3-substituted 5-amino-1,2,4-triazoles 1a-d with 2-cyclohexylidene cyclohexanone 2 in DMF. The compounds 3 were hydrogenated with sodium borohydride in ethanol to give 2,-substituted cis -4a',5,,6,,7,,8,,8a'-hexahydro-4,H -spiro[cyclohexane-1,9,-[1,2,4]triazolo[5,1- b]quinazolines] 4a-d in high yields. The reactions of alkylation, acylation and sulfonylation of the compounds 4 were studied. The structure of the synthesized compounds was determined on the basis of NMR measurements including HSQC, HMBC, NOESY techniques and confirmed by the X-ray analysis of 6 and 11b. The described synthetic protocols provide rapid access to novel and diversely substituted hydrogenated [1,2,4]triazolo[5,1- b]quinazolines. [source] SEQUENCE AND STRUCTURAL ANALYSIS OF ,-CARRAGEENAN-DERIVED OLIGOSACCHARIDES BY TWO-DIMENSIONAL NUCLEAR MAGNETIC RESONANCE,JOURNAL OF PHYCOLOGY, Issue 4 2010Wei Zhang ,-Carrageenan was hydrolyzed with mild hydrochloric acid and separated into a series of oligosaccharides, the sequences and structures of which were investigated by double-quantum filtered correlation spectroscopy (DQF-COSY), total correlation spectroscopy (TOCSY), heteronuclear multiple-quantum coherence (HMQC), and heteronuclear multiple-bond correlation (HMBC) techniques, respectively. The chemical structures and conformations of the individual sugar residues were identified, as well as the sequential connectivity of the oligosaccharides. The interresidue nuclear Overhauser effects (NOEs)/rotating frame Overhauser effects (ROEs) revealed an ordered helical structure of the carrageenan oligosaccharide chains. Therefore, a general two-dimensional (2-D) NMR methodology for the unambiguous sequence and structure analysis of ,-carrageenan-derived oligosaccharides was established in this study. [source] Structure elucidation and NMR assignments of two unusual monoterpene indole alkaloids from Psychotria stachyoidesMAGNETIC RESONANCE IN CHEMISTRY, Issue 9 2010Antonia Torres Ávila Pimenta Abstract Two unusual monoterpene indole alkaloids, stachyoside (1) and nor-methyl-23-oxo-correantoside (2), have been isolated from the aerial parts of Psychotria stachyoides. The structural elucidation of both compounds was performed by the aid of HRESIMS, FT-IR, and 1D- and 2D-NMR techniques including COSY, HSQC, HMBC, and NOESY. Copyright © 2010 John Wiley & Sons, Ltd. [source] Enhanced automated structure elucidation by inclusion of two-bond specific dataMAGNETIC RESONANCE IN CHEMISTRY, Issue 8 2010Steve F. Cheatham Abstract The availability of cryogenically cooled probes permits routine acquisition of data from low sensitivity pulse sequences such as inadequate and 1,1-adequate. We demonstrate that the use of cryo-probe generated 1,1-adequate data in conjunction with HMBC dramatically improves computer-assisted structure elucidation (CASE) both in terms of speed and accuracy of structure generation. In this study data were obtained on two dissimilar natural products and subjected to CASE analysis with and without the incorporation of two-bond specific data. Dramatic improvements in both structure calculation times and structure candidates were observed by the inclusion of the two-bond specific data. Copyright © 2010 John Wiley & Sons, Ltd. [source] Structure determination of selaginellins G and H from Selaginella pulvinata by NMR spectroscopyMAGNETIC RESONANCE IN CHEMISTRY, Issue 8 2010Yuan Cao Abstract Selaginellins G (1) and H (2), two new selaginellin derivatives, were isolated from the whole plant of Selaginella pulvinata. Their structures were elucidated, and complete assignments of the 1H and 13C NMR spectroscopic data were achieved by 1D and 2D NMR experiments (HSQC, HMBC, COSY and ROESY). Compound 1 displayed good antifungal activity against Candida albicans with an IC50 value of 5.3 µg/ml. Copyright © 2010 John Wiley & Sons, Ltd. [source] Acylated manoyl oxide diterpenes of Stemodia trifoliataMAGNETIC RESONANCE IN CHEMISTRY, Issue 6 2010Wildson Max B. da Silva Abstract Two new labdane diterpenes, 6,-malonyloxy-ethyl ester manoyl oxide and bis-6,-dioxymanoylmalonate, together with the known 6,-hydroxymanoyl oxide, 6,-malonyloxymaloyl oxide and betulinic acid were isolated from leaves of Stemodia trifoliata. Their structures were elucidated by spectroscopic studies (IR and HR-ESI-MS), including an extensive NMR (COSY, HSQC, HMBC and NOESY) analysis. Copyright © 2010 John Wiley & Sons, Ltd. [source] High-resolution NMR correlation experiments in a single measurement (HR-PANACEA)MAGNETIC RESONANCE IN CHEMISTRY, Issue 5 2010riks Kup Abstract Three important NMR pulse sequences, INADEQUATE, HSQC and three-dimensional HMBC have been combined into a single entity called high-resolution Parallel Acquisition NMR: an All-in-one Combination of Experimental Applications (HR-PANACEA) to provide reliable structural information about a small molecule in a single measurement. This exploits a recent instrumental development that permits simultaneous acquisition of signals from several nuclear species, using multiple receivers. Where high-precision values of the long-range heteronuclear splittings are important, selected regions of a large experimental data matrix are extracted and examined with the highest possible resolution. The J -doubling technique is then applied to derive precise values for these couplings. As proof of principle, the method is applied to the molecule of methyl salicylate, confirming the expected conformation of the COH moiety. Copyright © 2010 John Wiley & Sons, Ltd. [source] 1H,13C and 19F NMR data of N -substituted 6-(4-methoxyphenyl)-7H -pyrrolo[2,3- d]pyrimidin-4-amines in DMSO- d6MAGNETIC RESONANCE IN CHEMISTRY, Issue 3 2010Christopher Sørum Abstract Chemical shift assignment of seven N -substituted 6-(4-methoxyphenyl)-7H -pyrrolo[2, 3- d]pyrimidin-4-amines, six of which are fluorinated, have been performed based on 1H, 13C, 19F, and 2D COSY, HMBC and HSQC experiments. Copyright © 2009 John Wiley & Sons, Ltd. [source] Structure elucidation and complete NMR spectral assignments of two new oleanane-type pentacyclic triterpenoid saponins from the husks of Xanthoceras sorbifolia BungeMAGNETIC RESONANCE IN CHEMISTRY, Issue 11 2009Ying Guo Abstract Two new saponins were isolated from husks of Xanthoceras sorbifolia Bunge and their structures were elucidated as 3-O-[,-D-galactopyranosyl(1,2)]-,-L-arabinofuranosyl(1,3)-,-D-methyl glucuronic acid-21-O-(3,4-diangeloyl)-,-L-rhamnose-3,, 16,, 21,, 22,, 28,-pentahydroxyl-22-acetoxy-olean-12-ene(1) and 3-O-[,-D-galactopyranosyl(1,2)]-,-L-arabinofuranosyl(1,3)-,-D-methyl glucuronic acid-21,22-O-diangeloyl-3,,15,,16,,21,,22,,28,-hexahydroxyl-olean-12-ene(2) on the basis of 1D and 2D NMR (including 1H, 13C-NMR, 1H1H COSY, HSQC, HMBC and DEPT), ESI-MS spectrometry and chemical methods. Copyright © 2009 John Wiley & Sons, Ltd. [source] Complete assignments of 1H and 13C NMR data for new dibenzocyclooctadiene lignans from Kadsura oblongifoliaMAGNETIC RESONANCE IN CHEMISTRY, Issue 7 2009Hai-Tao Liu Abstract Two new dibenzocyclooctadiene lignans, named kadoblongifolins A (1) and B (2), and one new natural product dibenzocyclooctadiene lignan, named kadoblongifolin C (3), were isolated from the stems of Kadsura oblongifolia (K. oblongifolia), together with five known ones, schizanrin F (4), propinquanin C (5), schisantherin G (6), heteroclitin Q (7), kadsurarin (8). The structures of these new lignans were elucidated by a combination of high-resolution electron ionization mass spectrometry (HR-EI-MS), 1H NMR, 13C NMR, HMQC, HMBC, and NOESY spectra. Copyright © 2009 John Wiley & Sons, Ltd. [source] Complete assignments of 1H and 13C NMR spectral data for 7,7,-dihydroarylnaphthalene lignan lactonesMAGNETIC RESONANCE IN CHEMISTRY, Issue 6 2009Rosangela da Silva Abstract In this article we present a complete 1H and 13C NMR spectral analysis of three 7,7,-dihydroarylnaphthalene lignan lactones using modern NMR techniques such as COSY, HSQC, HMBC and NOE experiments. Complete assignment and homonuclear hydrogen coupling constant measurements were performed. Copyright © 2009 John Wiley & Sons, Ltd. [source] 1H and 13C NMR assignments for two new steroids from the coral Chromonephthea sp.MAGNETIC RESONANCE IN CHEMISTRY, Issue 4 2009Hua-Wei Geng Abstract Two new steroids isolated from EtOH extracts of the South China Sea soft coral Chromonephthea sp. were identified. One-dimensional (1D) and two-dimensional (2D) NMR experiments including COSY, HSQC, HMBC and NOESY were used for the determination of their structure. Copyright © 2008 John Wiley & Sons, Ltd. [source] Suppressing One-Bond Correlations in HMBC Spectra: Improved Performance for the BIRD,HMBC Pulse SequenceMAGNETIC RESONANCE IN CHEMISTRY, Issue 3 2009Julien Furrer Abstract An improved version of the BIRD,HMBC experiment is proposed. In comparison to the original version, the filtering (suppression of 1JCH signals) is accomplished using a double tuned G-BIRD filter positioned in the middle of the long-range correlations evolution period. Compensation of offset dependence by replacing the rectangular 180° pulses with the broadband inversion pulses (BIPs), with superior inversion performance and improved tolerance to B1 field inhomogeneity, significantly improves the sensitivity of the original BIRD,HMBC experiment. For usual one-bond coupling constants ranges (115,180 Hz), optimal results are easily obtained by adjusting the delays, ,, of the BIRD elements to an average J value. For larger ranges (e.g. 110,260 Hz), the use of a double tuned G-BIRD filter allows excellent suppression degrees for all types of one-bond constants present in a molecule, superior to the original scheme and other purging schemes. These attributes make the improved version of the BIRD,HMBC experiment a valuable and robust tool for rapid spectral analysis and rapid checks of molecular skeletons with a minimum spectrometer time. Copyright © 2009 John Wiley & Sons, Ltd. [source] Complete assignments of 1H and 13C NMR spectral data for three new triterpenoid saponins from Ilex hainanensis Merr.MAGNETIC RESONANCE IN CHEMISTRY, Issue 2 2009Xiao-Qing Chen Abstract Three new oleanane-type triterpenoid saponins, ilexhainanoside C, D and E, all with 24, 28-dioic acid groups, were isolated from the leaves of Ilex hainanensis. They were 3,-hydroxyolean-12-ene-24, 28-dioic acid-28- O -,- D -glucopyranoside(1), 3,, 19,-dihydroxyolean-12-ene-24, 28-dioic acid-28- O -,- D -glucopyranoside(2) and 3,, 29-dihydroxyolean-12-ene-24, 28-dioic acid-28- O -,- D -glucopyranoside(3). The structures of these three new compounds were elucidated and complete assignments of the 1H and 13C NMR spectroscopic data were achieved by 1D and 2D NMR experiments [heteronuclear single quantum coherence (HSQC), HMBC and rotational nuclear Overhauser effect spectroscopy (ROESY)]. Copyright © 2008 John Wiley & Sons, Ltd. [source] Complete multinuclear magnetic resonance characterization of a set of polyfluorinated acids and alcoholsMAGNETIC RESONANCE IN CHEMISTRY, Issue 2 2009Alexander A. Marchione Abstract A complete 1H, 19F, and 13C NMR assignment of a homologous series of polyfluorinated acids and alcohols is reported. These assignments were obtained chiefly through single and multiple-bond 1H,13C and 19F,13C correlation experiments (HSQC, HMBC). 19F NOESY experiments were required for assignment of two compounds with diastereotopic 19F nuclei in the CF2chain of the molecule. Copyright © 2008 John Wiley & Sons, Ltd. [source] Complete assignment of 1H and 13C NMR data of pravastatin derivativesMAGNETIC RESONANCE IN CHEMISTRY, Issue 1 2009Markus Bacher Abstract The complete 1H and 13C NMR data of 27 pravastatin derivatives are presented. Assignment was achieved by use of 1D and 2D NMR experiments (selective 1D NOE, COSY, NOESY, HSQC, HMBC). Copyright © 2008 John Wiley & Sons, Ltd. [source] NMR analysis of a series of substituted pyrazolo[3,4- d] pyrimidines-4-aminesMAGNETIC RESONANCE IN CHEMISTRY, Issue 1 2009Lígia M. Rodrigues Abstract A series of 21 substituted pyrazolo[3,4- d]pyrimidines-4-amines were studied by 1H and 13C NMR. The application of two-dimensional techniques, HMQC and HMBC, allowed the complete assignment of the spectra for all the compounds. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||||||||