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Communiols E-H: New polyketide metabolites from the coprophilous fungus Podospora communis
(2005-03-01)
Communiols E-H (1-4), four new polyketide-derived natural products containing furanocyclopentane, furanocyclopentene, cyclopentene, or γ-lactone moieties, have been isolated from two geographically distinct isolates of the ...
Communiols E-H: New polyketide metabolites from the coprophilous fungus Podospora communis
(2005-03-01)
Communiols E-H (1-4), four new polyketide-derived natural products containing furanocyclopentane, furanocyclopentene, cyclopentene, or γ-lactone moieties, have been isolated from two geographically distinct isolates of the ...
Bioactive guanidine alkaloids from Pterogyne nitens
(1995-12-01)
Bioactivity-guided fractionation of a methanolic CHCl 3 extract of the leaves of Pterogyne nitens afforded the known guanidine alkaloid pterogynidine [2] and three new guanidine alkaloids, nitensidines A [3], B [4], and C ...
Bioactive guanidine alkaloids from Pterogyne nitens
(1995-12-01)
Bioactivity-guided fractionation of a methanolic CHCl 3 extract of the leaves of Pterogyne nitens afforded the known guanidine alkaloid pterogynidine [2] and three new guanidine alkaloids, nitensidines A [3], B [4], and C ...
Proton double irradiation field-cycling nuclear magnetic resonance imaging: Testing new concepts and calibration methods
(Institute of Electrical and Electronics Engineers, 2020-11-11)
Double resonance experiments in field-cycling nuclear magnetic resonance (NMR) are powerful tools for the indirect detection of quadrupolar and electron resonances, dynamic nuclear polarization-induced signal amplification, ...
Estudio de cuasi-invariantes dipolares en cristales líquidos por coherencias cuánticas múltiples en resonancia magnética nuclear
(2011)
En este trabajo se estudia a través de un análisis teórico-experimental, la dinámica de espín en la creación de estados de cuasi-equilibrio en cristales líquidos (CLs), con la secuencia
de pulsos de radio frecuencias de ...
Using Proton Nuclear Magnetic Resonance (NMR) as a calibrating reference for magnetic field measurement instruments: Sensitive volume and magnetic field homogeneity
(Elsevier, 2020-02)
Nuclear magnetic resonance can be conveniently used to set up reference values of magnetic flux densities for the calibration of measurement instrumentation. Two measurement procedures are proposed based on the Fourier ...