Results 131 to 140 of about 873 (161)

New Cembranes from the Soft Coral Sarcophyton Species

Journal of Natural Products, 1999
Three new cembranes, including one with a 13-membered carbocyclic ring, have been isolated from the soft coral Sarcophyton sp.
, Iwagawa, , Nakashima, , Takayama, , Okamura, , Nakatani, , Doe, , Shibata   +6 more
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Naturally Occurring Cembranes from an Australian Sarcophyton Species

Journal of Natural Products, 2002
Naturally occurring cembranes 1-4 have been isolated from a Sarcophyton sp. These compounds have not previously been found to occur in nature but had been obtained as intermediates in a synthetic modification from tobacco. The absolute stereochemistries of 3 and 4 were determined.
Pham, NB, Butler, MS, Quinn, RJ
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ChemInform Abstract: The First Cembrane—Pseudopterane Cycloisomerization.

ChemInform, 1998
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.
A. D. RODRIGUEZ, J.‐G. SHI
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[Cembrane diterpenes in olibanum].

Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica, 2010
To study the constituents in the chloroform extract of olibanum and their antitumor activities.The compounds were isolated by chromatographic methods and their structures were identified on the basis of spectroscopic methods and X-ray diffraction. The antiproliferative effect of the compounds in human leukemia HL-60 cells was tested by viable cell ...
Feng, Wang, Zhanlin, Li, Tao, Liu, Huiming, Hua   +3 more
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Cembrane-derived diterpenoid having a carbotricyclic skeleton

Phytochemistry, 1987
Abstract A novel carbotricyclic diterpenoid, 18-oxo-3-virgene, has been isolated from the waxy, surface resins of tobacco.
Reiko Uegaki, Takane Fujimori, Nasuo Ueda, Akio Ohnishi   +3 more
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Oxidative transformations of cembrane diterpenoids III. Epoxycembrenes

Chemistry of Natural Compounds, 1977
1. It has been established that the epoxidation of cembrene with perbenzoic and peracetic acids takes place stereospecifically at each of the trisubstituted double bonds with the formation of 4S,5R-, 7S,8S-, and 11S,12S-monoepoxycembrenes, the structures and absolute configurations of which have been established by spectral methods. 2.
V. A. Raldugin, L. Ya. Korotkikh, A. I. Rezvukhin, V. A. Pentegova   +3 more
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ChemInform Abstract: Studies on the Synthesis of Cembranes

ChemInform, 1993
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.
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Cembrane, synthesis. An advanced intermediate for crassin acetate.

Tetrahedron Letters, 1991
Abstract The intramolecular alkyLation of a lithioalkyne with an allylic bromide produced the fourteen membered ring of crassin acetate. A nitrile oxide cycloaddition furnished the lactone and stereocenters at C1 and C14.
Marcus A. Tius, N. Kesavulu Reddy
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Cembrane Derivatives from Sarcophytum Glaucum

1977
In two previous publications1,2 we described the isolation and structure elucidation of several new cembrane derivatives isolated from the soft coral Sarcophytum lglaucum. The most prominent diterpene, sarcophine (1), which crystallizes from the crude petrol-ether extract and is believed to be one of the fish repellents which protect the coral against ...
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Oxidative transformations of cembrane diterpenoids. VI. Epoxidation of isocembrol

Chemistry of Natural Compounds, 1983
The stereochemistry of the epoxidation of the diterpene alcohol isocembrol has been studied. The main direction of attack of peracids is the C11 double bond of isocembrol, with the predominant formation of the 11S,12S-epoxide. The ratio of the monoepoxyisocembrols does not change appreciably with a variation in the temperature of the reaction or in the
V. A. Raldugin, N. I. Yaroshenko, V. I. Mamatyuk   +2 more
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