• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.994-1000
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• 2014

Synthesis of tetrahydroimidazo[1,2-a]pyridines and tetrahydropyrido[1,2-a] pyrimidines by a one-pot and three component reaction of ${\alpha}$-oxoketenedithioacetals, diamines and DMAD in water has been described. Different routes for accessing the desired compounds were examined and a few specially designed-substrates have been utilized further to afford the new imidazo and pyrido fused [1,8] naphthyridine tetracyclic compound by $S_NAr$ intramolecular cyclization.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1761-1764
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• 2010

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.240.2-240.2
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• 2003

A strategy for synthesis of the furan-fused tetracyclic core of xestoquinone and halenaquinone was explored through a model study. Methyl 8-oxo-4-methyl-4-phenyl-2,7-nonadiynoate was prepared from hydratroponitrile and 3-butyn-1-ol as starting materials. The intramolecular cycloaddition of this intermediate as a key step will be involved.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2978-2980
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• 2011

Enynals bearing an olefinic pendant were successfully cyclized via Huisgen-type [3+2] cycloaddition to the tetracyclic Pt-carbene complexes which would undergo insertion into a C-H bond of the ${\beta}$-position to afford the fused cyclopropane intermediates. Their tandem rearrangement afforded diverse types of spiranes depending on the tethered alkenes of the enynals.

• 정신신체의학
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• 제1권1호
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• pp.25-34
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• 1993

The author reviewed the general principle in the use of psychotropics for patients with renal diseases. who have psychiatric problems. Durgs which are dialyzable and metabolized or eliminated by kidney should not be used for patients with renal failure. However, lithium can be effectively used in a single dose$(300{\sim}600 mg/day)$ after each dialysis. though lithium has the double negative components. It is recommended that serum lithium level should be frequently monitored and the dose of lithium should be gradually increased to minimize its side effect Most of other psychotropics such as benzodiazepine anxiolytics tricyclic or tetracyclic antidepressants, and neuroleptics are metabolized in the liver, and they can be used in renal patients. The dose of these drugs should be reduced in two-thirds of the standard dose. In addition. it is necessary for liaison psychiatrists and other physicians to understand the interactions between psychotropics and drugs often used for treatment of renal diseases in order to prescribe psychotropics safely and effectively in renal patients.

• Journal of Microbiology and Biotechnology
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• 제22권11호
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• pp.1478-1481
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• 2012

Geldanamycin (GM) and its analogs are important anticancer agents that inhibit heat shock protein (Hsp) 90, which is a major chaperone protein in cancer cells. Accordingly, based on interest in obtaining novel natural GM derivatives, the potential of Streptomyces hygroscopicus JCM4427, a GM producer, was explored for novel natural GM derivative(s), resulting in the discovery of new GM analogs as a biosynthetic shunt product and intermediates from its fermentation broth. In this study, the fermentation, isolation, structure determination, and biological activity of the compounds, two new tetracyclic thiazinogeldanamycin (1) and 19-hydroxy-4,5-dihydrogeldanamycin (3), together with the three known 4,5-dihydrothiazinogeldanamycin (2), reblastatin (4), and 17-demethoxy-reblastatin (5), are described.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.138-139
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• 2002

The diverse, widespread, and exceedingly numerous family of natural products constructed from five carbon building-units and so comprising compounds with $C_{5}$, $C_{10}$, $C_{15}$, $C_{20}$, ${\cdots}$, $C_{40}$ skeletons (together with a few higher members) are synoymously termed terpenes or terpenoids. Among the terpene classes, the triterpenes ($C_{30}$ skeletones) form the largest group and are widely distributed in the plant kingdom, either in the free state or as esters or glycosides, although a few important members found in the animal kingdom such as squalene and a number of tetracyclic component including lanosterol. (omitted)

• 한국결정학회지
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• 제15권1호
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• pp.29-34
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• 2004

Cholesteryl hemisuccinate($C_{31}H_{50}O_4$)의 구조를 X-선 회절법으로 연구하였다. 이 화합물의 결정의 공간군은 $P2_12_12_1$이며, 단위세포내에 결정학적으로 서로 독립적인 4개의 분자들로 구성되어있다. 이들 분자들은 두 개의 분자들이 수소결합으로 결합된 hydrogen-bonded dimer 두쌍을 만들며, 결정내에서 단단히 결합되어있다. 두쌍의 hydrogen bonded dimer들은 각 각 b = 0.0과 b = 0.25 부근에서 head to head 배열을 이루며, c-축에 나란하게 배열되어 있다. 수소결합의 영향으로 결정의 녹는점이 $180^{\circ}C$으로 높다

• 생약학회지
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• 제4권4호
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• pp.167-172
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• 1973

Five crystalline substances, which are positive to$L_{IEBERMAN}-B_{URCHARD}$ reaction, were isolated from the unsaponifiable fraction of the fresh leaves of Betula latifolia $K_{OMAROV}$ (Betulaceae)by silica gel column chromatographic purification. Compound $A\;(C_{29}H_{50}O,\;mp\;136^{\circ}), \;B\;(C_{30}H_{52}O_3,\;mp\;165^{\circ}), \;C\;(C_{30}H_{52}O_4,\;mp\;237^{\circ}), \;D\;(C_{30}H_{52}O_3,\;mp\;196^{\circ})\;and\; E\;(C_{30}H_{52}O_4,\;mp\;121^{\circ})$ were isolated. Compound B was characterized as a new tetracyclic triterpenoid. Compounds A, C and D were identified as ${\beta}-sitosterol$, betulatriterpene C, and betulafolienetriol, respectively.

• 생약학회지
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• 제10권2호
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• pp.55-59
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• 1979

Mass spectra of the dammarane triterpenes having open side chain and $C_{20}-C_{25}-epoxy$ side chain were measured. Principal fragment ions were assigned and plausible mechanisms for the formation of the fragment ions were proposed. In general, the triter-penoids of $C_{20}-C_{25}-epoxy$ side chain. produce $h_{1}-species$ fragment ions by the deletion of side chain at $C_{20}-C_{22}$ bond and open side chain triterpenoids produce $h_{2}$ species fragmentions whose mass numbers are higher by two mass unit than those of $h_{1}$ species. The mass number of h species fragment ions will serve as the diagnostic tool for the elucidation of side chain structure of tetracyclic triterpenoids.