• Analytical Science and Technology
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• v.18 no.1
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• pp.85-88
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• 2005

Antiphase character of cross peaks in long-range COSY is modulated by changing the fixed delay time and used to assign diastereotopic methylene protons on rigid systems which could produce unpredictable NOE phenomena because of complicate coupling spins.

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.789-790
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• 2001

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.687-692
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• 2011

$^1H$ and $^{13}C$ NMR spectra of series of (E)-1-aryl-(2- and 3-thienyl)-2-propenones, that are aldol condensation products between 2- and 3-thiophenecarbaldehydes and m- and p-substituted acetophenones, were examined to make complete assignments of the chemical shifts. Long range couplings, $^4J$ and $^5J$, are observed in the $^1H-^1H$ COSY of both 2- and 3-thienyl compounds, which makes the elucidation of the conformation in solution possible. In contrast, the 2-furyl analogue shows the long range coupling phenomena, but the 3-furyl and phenyl analogues do not show similar phenomena.

• Korean Journal of Pharmacognosy
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• v.27 no.2
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• pp.123-128
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• 1996

From the leaves of Magnolia sieboldii a new aporphine-type alkaloid named magnoporphine was isolated. The structure of magnoporphine was all assigned by $^1H-^1H$COSY, $^1H-^{13}C$ COSY and $^1H-^{13}C$ long range NMR. In addition, costunolide, syringin, syringenin $4-O-{\beta}-cellobioside$ and echinacoside was isolated.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.67-67
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• 1995

Acyl-CoA:cholesterol acyltransferase (ACAT, EC 2.3.1.26) plays an important role in the control of intracellular free cholesterol content via its cholesterol esterifying activity. ACAT inhibitors are expected to be effective for treatment of atherosclerosis and hypercholesterolemia. In the course of a screening program for ACAT inhibitors from microbial sources, GERI-BP001 M, A, and B were isolated from the fermentation broth of a fungal strain. GERI-BP001 compounds were isolated from a culture broth of Aspergillus fumigatus F37 by acetone extraction, EtOAc extraction, SiO$_2$ column chromatography, and reverse phase HPLC. The structure of GERI-BP001 coumpounds were determined by $^1$H-NMR, $\^$l3/C-NMR, 2D-NMR, NOESY, and long range C-H COSY experiments. GERI-BP001 M, A, and B inhibit ACAT activity in an enzyme assay system using rat liver microsomes by 50% at concentrations of 75, 147, and 71 ${\mu}$M, respectively.