• Bulletin of the Korean Chemical Society
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• 제25권9호
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• pp.1351-1354
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• 2004

Tetracyclic 5-azaindole analogues were prepared by palladium-catalyzed sequential annulation of benzylidene(3-iodopyridinyl-4-yl)amine and 1-aryl substituted internal alkynes under $Pd(OAc)_2,\;n-Bu_4NCl,\;and Et_3N\;at\;120^{\circ}C.$ The synthetic procedure showed possible diversification of tetracyclic 5-azaindole analogues by varying the 1-aryl substituent in internal alkynes.

• 대한화학회지
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• 제36권6호
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• pp.925-932
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• 1992

${\beta}$-rhodomycinone(1)의 전 단계물질인 9,10-dideoxyrhodomycinone(30)의 전 합성이 이루어졌다. Phthalide sulfone 4를 몇 단계의 반응을 진행시켜서 naphthalide sulfone 12로 변형시킨 뒤, 음이온으로 변형된 naphthalide sulfone 12를 5-ethyl-1,3-cyclohexenone(21)과 Michael 부가반응시켜서 선형으로 결합된 tetracyclic 케톤 화합물 26을 좋은 수율로 얻었다. 화합물 26의 케톤기는 sodium borohydride로 환원시키고 메틸기로 보호하여 화합물 28을 얻었다. 9,10-Dideoxy-${\beta}$-rhodomycinone(30)은 pentamethoxy tetracyclic 화합물 28을 oxidative demethylation시키고 메틸기를 제거시켜서 합성하였다.

• 대한화학회지
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• 제58권4호
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• pp.423-427
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• 2014

• Bulletin of the Korean Chemical Society
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• 제23권11호
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• pp.1623-1628
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• 2002

Tetracyclic pyrido[2,3-b]azepine derivatives 4a-d and 4f as analogues of mirtazapine were synthesized via N-acyliminium ion cyclization by using aromatic rings such as benzene and thiophene ring as a ${\pi}-nucleophile$, and evaluated for the binding affinity for ${\alpha}2-adrenoceptor$. Among tested compounds, 2,3,9,13b-tetrahydro-1H-benzo[f]pyrrolo[2,1-a]pyrido[2,3-c]azepine (4a) was the most potent (Ki = 0.26 ${\mu}M)$ but showed about 3-fold less binding affinity than mirtazapine (Ki = 0.08 ${\mu}M)$ for a2-adrenoceptor.

• Natural Product Sciences
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• 제23권2호
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• pp.113-118
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• 2017

A new tetracyclic triterpenoid [4,4,24-trimethylcholesta-${\Delta}^{8,9;14,5;24,28}$-trien-$3{\beta},11{\beta},12{\alpha}$-triol-12-acetate, 3-sulfate] sodium salt (1), together with eight known compounds including ergosterol $5{\alpha},8{\alpha}$-endoperoxide (2), 1,9-dihydroxy-3-methoxy-2-methylpterocarpan (3), 3-O-${\beta}$-D-2-acetyl-amino-2-deoxyglucopyranoxyloleanoic acid (4), hydnocarpin (5), derrone (6), isovitexin (7), erythrinin C (8), and 5,4'-dihydroxy-2"-hydroxyisopropyldihydrofurano [4,5:7,8]-isoflavone (9), were isolated from the EtOAc soluble fraction of the methanol extract of aerial part of Desmodium uncinatum collected in the western highland of Cameroon. The structures of these compounds were established by comprehensive interpretation of their spectral data mainly including 1D- ($^1H$ and $^{13}C$), 2D-NMR($^1H$-$^1H$ COSY, HMQC, HMBC) spectroscopic and ESI-TOF-MS mass spectrometric analysis. The isolation of an integracide-like compound from plant origin is a very unusual finding.

• 생약학회지
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• 제1권2호
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• pp.1-10
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• 1970

The cyclization of geranylgeranyl pyrophosphate followed by ionization, proton elimination or cation center migration produces dicyclic, tricyclic and tetracyclic diterpenoids. The role of some of diterpenoids in animals is well known but their precise functions in plants remain to be explained.

• 대한화학회지
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• 제47권4호
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• pp.354-362
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• 2003

Xestoquinone의 퓨란-접합된 4환계화합물에 대한 합성전략을 모델연구를 통하여 조사하였다. 출발물질로서 3-butyn-1-ol을 이용하여, 5-iodo-1-methoxymethoxypentyne(5)이 5단계를 거쳐 제조되었다. Ethyl 2-phenylpropanoate와 5의 반응으로부터 ethyl 7-methoxymethoxy-2-methyl-2-phenyl-5-heptynoate(6)가 88%의 수득율로 얻어졌으며, 6으로부터 중요한 중간체인 methyl 9-oxo-4-methyl-4-phenyl-2,7-nonadiynoate(13)가 6단계를 거쳐 합성되었다. 13의 분자내 고리화반응은 5%의 수득율로 isobenzofuran 14을 생성하였으며, Lewis acid 존재 하에서 4환고리 구조로 전환되었다.

• Natural Product Sciences
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• 제14권3호
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• pp.152-155
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• 2008

An HPLC-ESI-MS method has been developed to identify and quantify two main tetracyclic triterpenes, alisol B 23-acetate and alisol C 23-acetate in the Alismatis Rhizoma (Taeg-Sa). The relative distribution of the two triterpenes in the methanolic extract of commercially available Alismatis Rhizoma was established by selective ion monitoring (SIM) mode via electrospray ionization (ESI) source. Regression equations revealed good linear relationship, and the correlation coefficients were 0.999 and 0.998 for alisol B 23-acetate and alisol C 23-acetate, respectively, between the peak areas of the components and their concentration in a range of $0.06-2.0{\mu}g/mL$. It was found that there were significant differences in the amount of alisol B 23-acetate and alisol C 23-acetate between Korean and Chinese origins. The results showed that this method could be used to identify the two components in Alismatis Rhizoma with high sensitivity and selectivity.

• 대한화학회지
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• 제33권6호
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• pp.644-650
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• 1989

Phthalide sulfone 2와 naphthalenone 6을 만들어서 Hauser-Rhee가 개발한 Michael addition의 새로운 고리 접합법으로 4개의 선형 고리화합물의 구조를 갖는 tetracyclic 화합물 11을 만들었다. 화합물 11의 ring A가 갖고 있는 중요한 이중결합을 이용해서 탄소수가 한 개 증가된 carbomethoxy 화합물 16으로 변형시키는 것은 Arndt-Eistert, Wolff rearrangement를 이용하였다. 그리고 나서 이들을 고리화 반응시킨 뒤 hydroxylation시켜서 최종 생성물인 (${\pm}$)-7-Deoxyaklavinone(18)를 합성하였다.

• 대한화학회지
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• 제30권1호
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• pp.109-117
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• 1986

항암항생제 Daunorubicin(2a)합성단계의 최종물질인 7,9-Dideoxydaunomycinone (32)를 3-methoxybenzoic acid(5)로 부터 합성하였다. 3-methoxybenzoic acid를 4-methoxy-3-(phenylsulfonyl)-1(3H)-isobenzofuranone(11)으로 변형시킨 뒤 Hauser와 Rhee가 개발한 고리접합법을 이용하여 trimethoxynaphthoate 16을 얻은 후에 phenylsulfonylnaphthofuranone 22로 변화시킨 뒤 이 물질을 7-(ethylenedioxy)-2-octenoate(23)과 Michael형태의 반응을 전개시켜 anthracenoate 24를 얻었다. Anthracenoate을 tetracyclic 화합물 28로 바꾼뒤 ring B와 C에 붙은 methyl기들을 제거하여 7,9-Dideoxydaunomycinone(32)를 만들었다.