Results 161 to 170 of about 3,861 (196)

Two new triterpenes fromAlstonia scholarisflowers

Natural Product Research, 2013
In the context of our previous communication on phytochemical studies of the ethanolic extract of flowers of Alstonia scholaris of Pakistan origin, these have resulted in the isolation of two new triterpenoids. One is of the oleanane type, alstoprenyol, 3-β-hydroxy-28-β-acetoxy-5-olea triterpene (1), the other is of ursane type, alstoprenylene 3β ...
Nighat, Sultana, Zafar Saeed, Saify, Muhammad, Saleem, Mustafa, Kamal   +3 more
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Antibacterial activity of Alstonia scholaris and Leea tetramera

Fitoterapia, 2003
The crude methanolic extracts of the leaves, stem and root barks of Alstonia scholaris and Leea tetramera on partitioning (petrol, dichloromethane, ethyl acetate, butanol) gave fractions exhibiting improved and broader spectrum of antibacterial activity. Especially the butanol fractions of A. scholaris and the root bark of L. tetramera.
M R, Khan, A D, Omoloso, M, Kihara
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Triterpenes ofAlstonia scholaris (dita-bark)

Experientia, 1957
Le triterpene majeur de l'ecorce d'Alstonia scholaris est identifie comme acetate d'α-amyrine et acetate de lupeol.
D, CHAKRAVARTI, R N, CHAKRAVARTI, R, GHOSE   +2 more
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Indole Alkaloids from the Leaves of Philippine Alstonia scholaris.

ChemInform, 2005
The first seco-uleine alkaloids, manilamine (1) (18-hydroxy-19,20-dehydro-7,21-seco-uleine) and N4-methyl angustilobine B (2), were isolated from the (pH 5) alkaloid extract of Philippine Alstonia scholaris leaves together with the known indole alkaloids 19,20-(E)-vallesamine (3), angustilobine B N4-oxide (4), 20(S)-tubotaiwine (5), and 6,7-seco ...
Allan Patrick G, Macabeo, Karsten, Krohn, Dietmar, Gehle, Roger W, Read, Joseph J, Brophy, Geoffrey A, Cordell, Scott G, Franzblau, Alicia M, Aguinaldo   +7 more
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Scholarine: An indole alkaloid of Alstonia scholaris

Phytochemistry, 1981
Abstract A new alkaloid designated scholarine was isolated from the leaves of Alstonia scholaris . It was (±) 12-methoxyechitamidine as determined by chemical and spectroscopic investigations.
Avijit Banerji, Arup K. Siddhanta
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Hypoglycemic Potential of Triterpenes from Alstonia scholaris

Pharmaceutical Chemistry Journal, 2013
A dichloromethane extract of air-dry leaves of Alstonia scholaris (L.) R. Br. contains a mixture of cycloeucalenol (1a), cycloartanol (1b) and lupeol (1c); lupeol acetate (2); and betulin (3). The structures of these triterpenes were elucidated by extensive 1D and 2D NMR spectroscopy and confirmed by comparison of their 13C NMR data to those reported ...
Consolacion Y. Ragasa, Kosta Fremmielle Lim, Chien-Chang Shen, Dennis D. Raga   +3 more
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ChemInform Abstract: Novel Alkaloids from Alstonia scholaris.

ChemInform, 2010
AbstractNovel alkaloids, scholarisine I (I) and scholarisine II (II), are isolated, and a possible biogenesis is proposed.
Xiang‐Hai Cai, Jian‐Hua Shang, Tao Feng, Xiao‐Dong Luo   +3 more
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Evaluation of Alstonia scholaris leaves for broncho-vasodilatory activity

Journal of Ethnopharmacology, 2005
The present study demonstrates that the ethanol extract of Alstonia scholaris (Apocynaceae) leaves induced pronounced bronchodilatory activity in anaesthetized rats with the probable involvement of prostaglandins. However, in vitro preparations of guinea-pig trachea did not confirm this property, indicating that bronchodilation is not due to the direct
Shabana, Channa, Ahsana, Dar, Shakeel, Ahmed, , Atta-ur-Rahman   +3 more
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ChemInform Abstract: Phytochemical Studies on Alstonia scholaris.

ChemInform, 2010
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Nighat Sultana, Muhammad Saleem
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A Cage-Monoterpene Indole Alkaloid from Alstonia scholaris

Organic Letters, 2008
An unprecedented cage-like alkaloid, scholarisine A was isolated from the leaves of Alstonia scholaris and its structure determined on the basis of 1D and 2D NMR, FTIR, UV, and high-resolution mass spectroscopic data. This alkaloid might be derived from picrinine via oxygenation, rearrangement, and lactonization.
Xiang-Hai, Cai, Qin-Gang, Tan, Ya-Ping, Liu, Tao, Feng, Zhi-Zhi, Du, Wei-Qi, Li, Xiao-Dong, Luo   +6 more
openaire   +2 more sources