Asymmetric Synthesis of the C15–C32 Fragment of Alotamide and Determination of the Relative Stereochemistry

Alotamide is a cyclic depsipetide isolated from a marine cyanobacterium and possesses a unique activation of calcium influx in murine cerebrocortical neurons (EC50 4.18 µM). Due to its limited source, the three stereocenters (C19, C28, and C30) in its polyketide fragment remain undetermined. In this study, the first asymmetric synthesis of its polyketide fragment was achieved. Four relative possible diastereomers were constructed with a boron-mediated enantioselective aldol reaction and Julia–Kocienski olefination as the key steps. Comparison of 13C NMR spectra revealed the relative structure of fragment C15–C32 of alotamide.

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Total assignment of 1H and 13C NMR spectra of marchantins isolated from liverworts and its application to structure determination of two new macrocyclic bis(bibenzyls) from and

Tetrahedron Letters ◽

10.1016/s0040-4039(00)94937-2 ◽

1985 ◽

Vol 26 (39) ◽

pp. 4735-4738 ◽

Cited By ~ 39

Author(s):

Motoo Tori ◽

Masao Toyota ◽

Leslie J. Harrison ◽

Keiko Takikawa ◽

Yoshinori Asakawa

Keyword(s):

13C Nmr ◽

Structure Determination ◽

Nmr Spectra ◽

13C Nmr Spectra ◽

1H And 13C Nmr

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Computer-aided determination of microfragmentary composition of organic molecule by mass-, 1H- and 13C-NMR spectra

Computers & Chemistry ◽

10.1016/0097-8485(94)80026-x ◽

1994 ◽

Vol 18 (1) ◽

pp. 81-88

Author(s):

B.G. Derendyaev ◽

K.S. Lebedev ◽

S.A. Nekhorshev ◽

S.P. Kirshansky

Keyword(s):

13C Nmr ◽

Nmr Spectra ◽

Organic Molecule ◽

13C Nmr Spectra ◽

1H And 13C Nmr ◽

Computer Aided

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Statistical determination of chemical composition and monomer sequence distribution of poly(methyl methacrylate-co-tert-butyl methacrylate)s by multivariate analysis of 13C NMR spectra

Polymer Journal ◽

10.1038/pj.2012.110 ◽

2012 ◽

Vol 44 (8) ◽

pp. 808-814 ◽

Cited By ~ 6

Author(s):

Hikaru Momose ◽

Tomoya Maeda ◽

Kosuke Hattori ◽

Tomohiro Hirano ◽

Koichi Ute

Keyword(s):

Multivariate Analysis ◽

Chemical Composition ◽

13C Nmr ◽

Nmr Spectra ◽

Butyl Methacrylate ◽

13C Nmr Spectra ◽

Sequence Distribution ◽

Monomer Sequence ◽

Statistical Determination

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Determination of the tacticities of ring-opened metathesis polymers of symmetrical 5,6-disubstituted derivatives of norbornene and norbornadiene from the 13C NMR spectra of their hydrogenated derivatives

Journal of Molecular Catalysis A Chemical ◽

10.1016/s1381-1169(98)00101-0 ◽

1998 ◽

Vol 133 (1-2) ◽

pp. 115-122 ◽

Cited By ~ 14

Author(s):

V Amir-Ebrahimi ◽

D.A.K Corry ◽

J.G Hamilton ◽

J.J Rooney

Keyword(s):

13C Nmr ◽

Nmr Spectra ◽

13C Nmr Spectra ◽

Derivatives Of

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Photomediated asymmetric synthesis of (–)-cupareneElectronic supplementary information (ESI) available: experimental procedures and data including copies of 1H-NMR and 13C-NMR spectra for all new compounds, and NOESY spectra for compounds 9, 10, 11, 15 and 16. See http://www.rsc.org/suppdata/cc/b3/b300815k/

Chemical Communications ◽

10.1039/b300815k ◽

2003 ◽

pp. 1072-1073 ◽

Cited By ~ 17

Author(s):

Richard S. Grainger ◽

Aslam Patel

Keyword(s):

Asymmetric Synthesis ◽

1H Nmr ◽

13C Nmr ◽

Nmr Spectra ◽

Supplementary Information ◽

13C Nmr Spectra ◽

New Compounds ◽

Noesy Spectra

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Determination of the Structure of Chlorobutyl and Bromobutyl Rubber by NMR Spectroscopy

Rubber Chemistry and Technology ◽

10.5254/1.3536147 ◽

1987 ◽

Vol 60 (4) ◽

pp. 636-646 ◽

Cited By ~ 27

Author(s):

Chia Yeh Chu ◽

Kenneth Norman Watson ◽

Rastko Vukov

Keyword(s):

Nmr Spectroscopy ◽

13C Nmr ◽

Nmr Spectra ◽

Broad Band ◽

Type Structure ◽

13C Nmr Spectra ◽

Model Compounds ◽

1H And 13C Nmr

Abstract An analysis of the 1H and 13C NMR spectra of the chlorobutyl and bromobutyl rubbers was performed. Peaks were assigned based on evidence from broad-band decoupled, off-resonance decoupled, selectively decoupled and J-modulated spectra, the known characterization of butyl rubber and halogenation studies on model compounds. The assignment of the minor peaks indicated that the exomethylene-type structure is predominant in both halogenated rubbers. They also contain some nonhalogenated isoprenyl units. Bromobutyl rubber also contains some α-bromomethyl-type structures resulting from rearrangement of the exomethylene structure. The presence of endo-type structures will require further study for confirmation.

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ChemInform Abstract: Substituent Effects in 13C NMR Spectra of Diastereomeric Chalcone Dihalides. Part 10. First Synthesis and Determination of Configuration of threo-Chalcone Bromohydrins.

ChemInform ◽

10.1002/chin.199219137 ◽

2010 ◽

Vol 23 (19) ◽

pp. no-no

Author(s):

F. G. WEBER ◽

C. KAATZ ◽

R. RADEGLIA ◽

H. KOEPPEL

Keyword(s):

13C Nmr ◽

Nmr Spectra ◽

Substituent Effects ◽

13C Nmr Spectra

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Computer-Assisted Analysis system of 13C-NMR Spectra Desinged for Composition Determination of Cosmetic Products (II)

Journal of Society of Cosmetic Chemists of Japan ◽

10.5107/sccj.23.111 ◽

1989 ◽

Vol 23 (2) ◽

pp. 111-117

Author(s):

Kikuko Sugawara ◽

Hajime Kikuchi ◽

Keiichi Honda

Keyword(s):

13C Nmr ◽

Nmr Spectra ◽

Computer Assisted ◽

13C Nmr Spectra ◽

Cosmetic Products ◽

Composition Determination ◽

Analysis System ◽

Assisted Analysis

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Asymmetric aziridination of chalcones catalyzed by a novel backbone 1,8-bisoxazolinylanthracene (AnBOX)-copper complexElectronic supplementary information (ESI) available: characterization data, 1H NMR and 13C NMR spectra for the ligand AnBOX 1 and all unknown compounds 3, and HPLC chromatograms for the determination of the ee values of all the aziridine derivatives 3. See http://www.rsc.org/suppdata/cc/b4/b404134h/

Chemical Communications ◽

10.1039/b404134h ◽

2004 ◽

pp. 1616 ◽

Cited By ~ 46

Author(s):

Jiaxi Xu ◽

Linge Ma ◽

Peng Jiao

Keyword(s):

1H Nmr ◽

13C Nmr ◽

Nmr Spectra ◽

Supplementary Information ◽

13C Nmr Spectra ◽

Asymmetric Aziridination

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Modeling of Antioxidant Activity, Polyphenols and Macronutrients Content of Bee Pollen Applying Solid-State 13C NMR Spectra

Antioxidants ◽

10.3390/antiox10071123 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1123

Author(s):

Sylwester Mazurek ◽

Roman Szostak ◽

Mateusz Kondratowicz ◽

Magdalena Węglińska ◽

Agnieszka Kita ◽

...

Keyword(s):

Antioxidant Activity ◽

Solid State ◽

Nmr Spectroscopy ◽

13C Nmr ◽

Nmr Spectra ◽

13C Nmr Spectra ◽

Bee Pollen ◽

Relative Standard ◽

Solid State 13C Nmr

An application of solid 13C nuclear magnetic resonance (NMR) spectroscopy for the determination of macronutrients, total polyphenols content, antioxidant activity, N C S elements, and pH in commercially available bee pollens is reported herein. Solid-state 13C NMR spectra were recorded for homogenized pollen granules without chemical treatment or dissolution of samples. By combining spectral data with the results of reference analyses, partial least squares models were constructed and validated separately for each of the studied parameters. To characterize and compare the models’ quality, the relative standard errors of prediction (RSEP) were calculated for calibration and validation sets. In the case of the analysis of protein, fat and reducing sugars, these errors were in the 1.8–2.5% range. Modeling the elemental composition of bee pollen on the basis of 13C NMR spectra resulted in RSEPcal/RSEPval values of 0.3/0.6% for the sum of NHCS elements, 0.3/0.4% for C, 1.8/1.9% for N, and 4.2/6.1% for S quantification. Analyses of total phenolics and ABTS antioxidant activity resulted in RSEP values in the 2.7–3.5% and 2.8–3.8% ranges, respectively, whereas they were 1.4–2.1% for pH. The obtained results demonstrate the usefulness of 13C solid-state NMR spectroscopy for direct determination of various important physiochemical parameters of bee pollen.

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