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171.
Yu Xin LIU Xiao Tian LIANG* Institute of Materia Medica Chinese Academy of Medical Sciences &Peking Union Medical College Xian NongTan Street Beijing 《中国化学快报》2001,(1)
In our research on the ring enlargement of certain N-heterocycles, a general procedure for the ring enlargement with the insertion of an extra -CH2- was improved and shown in Scheme I1.Scheme IThe procedure had been carried out with such N-heterocycles as 2-methyl-1,2,3,4-tetrahydroisoquinoline2, tetrahydroberberine and strychnine3 with expected results. Thus, the procedure shown in Scheme I provides a new approach to the synthesis of larger N-heterocycles.Isoindolo[1,2-b][3]benzazepines a… 相似文献
172.
173.
Zhan Zhu LIU Shi Zhi CHEN* Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 《中国化学快报》2001,(3)
1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid is a type of naturally occurring bio-active alkaloid1. Moreover, it can be used as building block for the synthesis of other natural products containing the 1,2,3,4-tetrahydroisoquinoline moiety2. Compound 2 was an intermediate in our attempt to the total synthesis of Ecteinascidin analogs. We employed the Bishler-Napieralski reaction to prepare this product and refluxed the N-acetyl phenylalanine compound 1 in POCl3/benzene. However, we fail… 相似文献
174.
Xiao Xia YE Ji Shuang CHEN Ming Kui WANG Ke Xin HUANG Li Sheng DING* Chengdu Institute of Biology Chinese Academy of Sciences Chengdu Department of Chemistry Wenzhou Medical College Wenzhou College of Life Science Zhejia 《中国化学快报》2000,11(11)
As a part of an investigation on plant of the genus Notoseris (Asteraceae), an endemic genus of seed plants of China1, we studied the chemical constituents of N. psololepis Shih. A new sesquiterpene lactone glucoside, named notoserolide C (1) was isolated from the methanolic extract of the whole plant of N. psilolepis by repeated column chromatography (MCI GEL, normal and reversed phase silica gel). This compound showed antibacterial activity against Bacillu cereus.Figure 1. The key HMB… 相似文献
175.
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177.
Xue Mei NIU Sheng Hong LI Li Yan PENG Gao Xiong RAO Han Dong SUN* Laboratory of Phytochmistry Kunming Institute of Botany Academia Sinica Kunming Yunnan College of Traditional Chinese Medicine Kunming 《中国化学快报》2001,(3)
Limonia crenulata Roxb. (Rutaceae), a small tree widely distributed in dry warm regions of southeastern Asia, has been reported to have antiepileptic, purgative and sudorific effects and is used for colic trouble and cardialgia1. Various parts of this plant have been employed in indigenous medicine. Our investigation on its stems led to the isolation of one new alkaloid, crenulatine 1, together with three known ones, 4-methoxy-6- hydroxy-1-methyl-2-quinolone2, N-benzoyltyramine methyl ether2,… 相似文献
178.
Wei Hong SONG Xuan Zhen JIANG* Department of Chemistry Zhejiang University Hangzhou 《中国化学快报》2001,(3)
Dimethyl malonate (DMM) is an important organic synthesis intermediate. Traditional synthetic method by reaction of mono-chloroacetic acid with sodium cyanide1 is poisonous and complicated. Therefore, an interest in green synthesis routes of DMM has risen greatly. The several processes for preparing DMM by carbonylation of methyl chloroacetate catalyzed by Co2(CO)8 have been reported2~5. However, Co2(CO)8 is unstable and must be prepared under high pressure (12 Mpa). Moreover, the yield… 相似文献
179.
Yong WU* Mei GUAN Pei Jie LI Cheng XU Xiao Chun WU School of Pharmacy West China University of Medical Sciences Chengdu The First Hospital West China University of Medical Sciences Chengdu 《中国化学快报》2001,(1)
Since the last decade, there has been a growing interest in the development of analogues of 1(, 25- dihydroxyvitamin D3 1 with low calcemic effect but increased cell differentiating ability1. Among side chain and the A-ring modifications of 1, the 1(, 25- dihydroxy-22-oxo-vitamin D3 22 and 19-nor-1(, 25- dihydroxyvitamin D3 33 have shown much lower calcemic effect and stronger cell differentiating ability than 1. In this paper, we reported synthesis of 19-nor-1(, 25-dihydroxy-22-oxo-vitamin … 相似文献
180.
Cheng Lu ZHANG Ping Yan BIE Xuan Jia PENG Xin Fu PAN* Department of Chemistry National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2002,13(10)
Most diterpenoids exhibit significant bioactivities, such as antidermatophytic, antibact- erial, and antioxidant. Although a large number of aromatic tricyclic diterpenoids have been isolated, there are a few of them having ethyl substituent. The synthesis of this type diterpenoids has been seldom reported. In order to further study the relationship between the structure and bioactivities of the diterpenoid, we extended the diterpene synthesis1,2,3. It is desirable to report herein the syn… 相似文献