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Synthetic Studies of Et-743, Preparation of A Racemic Amino Alcohol Precursor

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Chinese Chemical Letters 2003年第11期14卷 1127-1129页

作者： Zhan Zhu LIU shi zhi chen Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050

A mild two-step method was used to cleave the lactam ring of the tricyclic intermediate 1. A key racemic amino alcohol precursor 5 for the construction of Et-743 skeleton was synthesized from 1 through four steps in ... 详细信息

关键词： Et-743 lactam cleavage.

Construction of the Skeleton of Phthalascidin, Mechanism of the Formation of the Key Tricyclic Lactam Intermediate

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Chinese Chemical Letters 2002年第8期13卷 701-704页

作者： Zhan Zhu LIU Ye WANG shi zhi chen Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050

The mechanism of the formation of a key tricyclic lactam intermediate 3 was studied. It was found that the E-form compound 3 was transformed from the Z-form compound 4. The formation of 4 was a kinetically controlled process while the formation of 3 was a thermodynamically favorable one. A possible mechanism was given in this paper.

关键词： Lactam phthalascidin mechanism Et-743.

Formation of Benzyl Oxazole, A Competitive Path with the Classical Bishler-Napieralski Reaction

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Chinese Chemical Letters 2001年第11期12卷 947-950页

作者： Zhan Zhu LIU Ye Feng TANG shi zhi chen Institute of Materia Medica Chinese Academy of Material Sciences&Peking Union Medical CollegeBeijing 100050

Several aromatic ring-substituted N-acetyl-phenylalanine methyl esters were treated with POCl3 in refluxing benzene, which is the typical condition of B-N reaction. It was found that the normal B-N product 3, 4-dihydroisoquinoline-3-carboxylic acid methyl ester and/or 5-benzyl-2-methyl-4-methoxy oxazole could be obtained. The result depended mainly upon the electron-donating property of the substitutes on the benzene ring. Strong electron-donating groups located at para- or ortho- to the cyclization site will facilitate the formation of the normal B-N product 2. On the other hand, the absence or weak electron-donating groups tended to yield the oxazole product 3. It was established that the formation of benzyl oxazole is the competitive path with the B-N reaction. In this article, an explanation was given based on the mechanism of Bishler-Napieralski reaction.

关键词： Bishler-Napieralski reaction benzyl oxazole 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid N-acetyl-phenytalanine methyl ester

New Approach to Synthesis of 6,7-Dimethoxyisatin

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Chinese Chemical Letters 2003年第5期14卷 468-470页

作者： Hong Min MA Zhan Zhu LIU shi zhi chen Institute of Materia Medica Peking Union Medical College&Chinese Academy of Medical SciencesBeijing 100050

A new approach to synthesis of 6,7-dimethoxyisatin is reported. 2-nitro-3, 4- dimethoxy mandelonitrile in glacial acetic acid was treated with the solution of stannous chloride in hydrochloric acid to give 6, 7-dimet... 详细信息

关键词： Isatin stannous chloride mandelonitrile synthesis.

Regioselective Bromination of 3, 4-Dimethoxytoluene with N-Bromosuccinimide

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Chinese Chemical Letters 2003年第4期14卷 371-374页

作者： Hong Min MA Zhan Zhu LIU shi zhi chen Institute of Materia Medica Peking Union Medical College&Chinese Academy of Medical SciencesBeijing 100050

The selective brominations of 3, 4-dimethoxytoluene with N-bromosuccinimide were reported. The nuclear and side-chain brominated products were obtained under different reaction conditions. The mechanism was also discu... 详细信息

关键词： Bromination 3, 4-dimethoxy toluene N-bromosucinimide regioselective bromination.

An Efficient Synthetic Strategy for Construction of Functionalized Pentacyclic Skeleton of ecteinascidin-saframycin Alkaloids

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Chinese Chemical Letters 2006年第7期17卷 853-856页

作者： Ye WANG Zhan Zhu LIU Ye Feng TANG shi zhi chen Institute of Materia Medica Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100050

Two functionalized pentacyclic compounds 12a, 12b were constructed via a highly efficient synthetic route, employing a tricyclic amino aldehyde as the key intermediate. The crucial steps involved coupling of two segme... 详细信息

关键词： Ecteinascidin saframycin tetrahydroisoquinoline Pictet-Spengler reaction.

Synthesis and Antitumor Activity of an Analog of Phthalascidin

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Chinese Chemical Letters 2006年第10期17卷 1279-1282页

作者： Ye WANG Yan Li ZHOU Zhan Zhu LIU shi zhi chen Xiao Guang chen Institute of Materia Medica Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100050

An analog of phthalascidin （Pt-650） was synthesized with an improved synthetic route. With precursor 2 as the starting material, compound 1 was prepared through 4 steps in a total yield of 47%. In vitro antitumor test of this Pt-650 analog showed that it possessed strong toxicity against a number of tumor cell lines including A2780, A549, Bel-7402, BGC-823, HELA, KB, KeTr3 and HCT-8.

关键词： Ecteinascidin phthalascidin tetrahydroisoquinoline antitumor.

Revolution in thermoelectric cooling using PbSe thermoelectrics by grid plainification

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Science China Materials 2024年第5期67卷 1672-1673页

作者： Xiao-Lei shi Qingfeng Liu zhi-Gang chen School of Chemistry and Physics ARC Research Hub in Zero-emission Power Generation for Carbon Neutralityand Centre for Materials ScienceQueensland University of TechnologyBrisbaneQueensland4000Australia State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing211816China

Thermoelectric materials and devices enable direct conversion between heat and electricity,holding potential applications in thermoelectric power generation,localized cooling,and electronic thermal management[1].Howev... 详细信息

关键词： enable thermoelectric constrained

Stereoselective synthesis of 3-butylphtalide via CBS catalytic reduction

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Chinese Chemical Letters 2007年第6期18卷 653-655页

作者： Geng Xu[a] Zhan Zhu Liu[a]&Email:liuzhanzhu@*** Jing Hua Yang[a] shi zhi chen[a] Hui Ying Yang[b]&Email:yanghuiying@*** [a]Institute of Materia Medica Peking Union Medical College & Chinese Academy of Medical Science Beijing 100050 China [b]National Institute for the Control of Pharmaceutical and Biological Products Beijing 100050 China

Optically active 3-butylphtalide of high enantiomeric excesses (up to 93% e.e.) was synthesized from the reduction of o-pentanoylbenzoic ester with borane using B-methyloxyoxazaborolidine (1b) as the chiral catalyst.

关键词： Stereoselective synthesis 3-Butylphtalide CBS catalytic reduction o-Pentanoylbenzoic ester