• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.672-674
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• 2014

• YAKHAK HOEJI
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• v.33 no.4
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• pp.226-228
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• 1989

In connection with the synthesis of the biologically active pimarane diterpenoids, some synthetic routes to the quaternary carbon unit were examined. Especially, Claisen rearrangement of allyl acetates prepared from acetol provided ${\gamma}-hydroxy$ acid containing vinyl substituent as the desired unit.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1589-1591
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• 2013

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.692-697
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• 1996

This experiment was conducted to determine the influences of growth stage, stalk position and growth environment on duvatrienediols(DVT-diols) and cis-abienol production in Nicotiana tabacum L. The leaves of plants at transplanting stage contained very small amount of duvatrienediols and cis-abienol. Comparing leaves on different stalk position at flowering stage, upper and middle leaves contained more DVT-diols and cis-abienol than lower leaves. Plants grown under controlled environmental room at 3$0^{\circ}C$ contained more DVT-diols and cis-abienols than room at 18$^{\circ}C$, $25^{\circ}C$ and glass room. Tobacco plant grown under field condition produced lower levels of duvatrienediols and cis-abienol contents than glass room-grown plants. The amounts of duvatrienediols and cis-abienol of tobacco leaves significantly decreased after rain under field conditions.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1379-1385
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• 2017

The content of taxol in the bark of yews is very low, and this is not affordable from the environmental point of view. Thus, it is a necessity to look for alternative sources of taxol production to solve its supply. Currently, a large portion of the taxol in the market comes from chemical semi-synthesis, but the semi-synthetic precursors such as baccatin III and 10-deacetyl-baccatin III are extracted from needles and twigs of yew trees. Taxol-producing fungi as a renewable resource is a very promising way to increase the scale of taxol production. Our group has obtained a taxol-producing endophytic fungus, Aspergillus niger subsp. taxi HD86-9, to examine if A. niger can produce the taxanes. Six compounds from the fermentation broth of strain HD86-9 were isolated and identified by $^1H$ NMR, $^{13}C$ NMR, and ESI-MS. The results showed that the six compounds included four taxane diterpenoids (taxol, cephalomannine, baccatin III, and 10-deacetyl-baccatin III) and two non-taxane compounds (${\beta}-sitosterol$ and flavonoid isovitexin). The study verified that the taxanes can be produced by the A. niger, which is very important to taxol production via chemical semi-synthesis. Additionally, the finding is potentially very significant to solve the taxol semi-synthetic precursors extracted from needles and twigs of yew trees, and the precursor production can be easily increased through the culture condition optimization, genetic breeding, and metabolic engineering of the A. niger.

• Natural Product Sciences
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• v.15 no.1
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• pp.50-54
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• 2009

A simple and reliable reversed phase HPLC method was developed to determine pharmacologically active compounds ent-continentalic acid, kaurenoic acid, and continentalic acid from the roots of Aralia cordata. Quantitative analysis of diterpenoids of A. cordata were performed by reverse phase C-18 column using a isocratic of acetonitrile : 0.1% trifluoroacetic acid(70:30) with UV detection at 205 nm. The correlation coefficients of each calibration curve of ent-continentalic acid, kaurenoic acid, and continentalic acid were 0.9987, 0.9983, and 0.9986, respectively. The detection limit of ent-continentalic acid, kaurenoic acid, and continentalic acid were $0.5{\sim}1.0\;{\mu}g/mL$, respectively. The contents of ent-continentalic acid (1), kaurenoic acid (2), and continentalic acid (3) of the roots of A. cordata collected from seventeen district markets in Korea were $0.09{\sim}0.75\;mg/g$, $1.09{\sim}5.43\;mg/g$, and $2.69{\sim}9.08\;mg/g$, respectively.

• Archives of Pharmacal Research
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• v.26 no.11
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• pp.898-901
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• 2003

Three compounds were isolated from the stem barks of Croton robustus. Their structures were elucidated as trachyloban-19-oic, acid, trachyloban-19-ol and poilaneic acid by spectroscopic analysis. Among them, trachyloban-19-ol and methyl trachyloban-19-oate exhibited weak cytotoxic activity against gastric carcinoma and colon carcinoma with $ED_{50}$ of 9.2, 9.6 and 8.3, $9.1{\mu\textrm{g}}/mL$, respectively.

• Natural Product Sciences
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• v.3 no.1
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• pp.14-18
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• 1997

Two new diterpenoids, orientalin A (1), and B (2), have been isolated together with six known compounds, kirenol (3), $ent-16{\beta},17-dihydroxykauran-19-oic$ acid (4), $ent-16{\beta},17-dihydroxykauran-19-oic$ $acid-16{\beta},l7-acetonide$ (5), $3,7-dimethylquercetin$ (6), ${\beta}-sitosterol$ (7), and daucosterol (8) from the ethanol extract of Siegesbeckia orientalis (Compositae). Their chemical structures have been elucidated as $ent-15-acetoxy-2{\alpha},16,19-trihydroxypimar-8(14)-ene$ (1), $ent-16-acetoxy-2{\alpha},15,19-trihydroxypimar-8(14)-ene$ (2), respectively, on the basis of chemical and spectral evidence.

• Korean Journal of Pharmacognosy
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• v.25 no.4 s.99
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• pp.319-327
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• 1994

A new diterpene, agastanol[1] with dehydroagastol[2] was isolated from th root of Agastache rugosa, and their structures were elucidated by chemical and instrumental analysis. Agastanol[1], its derivatives, agastanone[3] and methylagastanol[5], and dehydroagastol[2] showed cytotoxic activites against in vitro human cancer cell lines. Agastanol[1] showed weak antifungal activity against Trichophyton rubrum.

• Archives of Pharmacal Research
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• v.27 no.5
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• pp.467-470
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• 2004

Comparative molecular field analysis and comparative molecular similarity indices analysis were performed on twenty five analogues of pimarane COX-2 inhibitor to optimize their cyclooxygenase-2 (COX-2) selective anti-inflammatory activities.