Lanostane-type triterpene

Kitagawa, I., Kobayashi, M., Son, B.W., Susuki, S., and Kyogoku, Y. (1989) Marine natural products. XIX. Pervicosides A, B, and C, lanostane-type triterpene-oligoglycoside sulfates from the sea cucumber Holothuria pervicax. Chem. Pham. Bull, 37, 1230-1234. 

Kobayashi, M., Hori, M., Kan, K., Yasuzawa, T., Matsui, M., Suzuki, S., and Kitagawa, I. (1991) Marine natural products. XXVII. Distribution of lanostane-type triterpene oligoglycosides in ten kinds of Okinawan sea cucumbers. Chem. Pham. BuU., 39, 2282-2287. 

Lanoatarol, kryptosterol 5a-lanosta-8(9),24-dien-3P-ol, a tetracyclic triterpene alcohol. M, 426.7, m.p. 140 °C, [o]i3 + 60° (CHCI3). L. is also a zoosterol (see Sterols) present in large amounts in the wool fat of sheep. Structurally, it is based on the hydrocarbon 5a-lanostane ring system. It is biosynthesized from squalene, via 2,3-epoxysqualene, and is an important intermediate in the synthesis of all further tetracyclic triterpenes of the lanostane type and of the steroids. 

Widespread reports indicate that, in addition to their anti-inflammatory role, triterpenes have other activities. Triterpenoids have been found to possess cytotoxic, antimicrobial and interesting effects on metabolism. Triterpenoids with antitumour activity include oleanane, lanostane, lupane, friedelane, hopane and quassionoid types. Glycyrrhetinic acid has been described as an antiviral, hypolipidemic and anti-atherosclerotic agent. Cucurbitacins B and E, and oleanolic acid possess a potent protective action on the liver, and ganoderic acid and its derivatives have been shown to be inhibitors of cholesterol biosynthesis. Lanostane derivatives, like suberosol, have also been found to inhibit HIV replication in H9 lymphocytes [1,3]. 

The lanostanes are the most relevant group of the tetracyclic triterpenes (Tables 12-13). Many of this type of compounds are described as antiinflammatories and their mechanism of action has been studied frequently. Cycloartenol and some 3,4-seco-lanostane derivatives have been reported to have activity also. 

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