5356-56-9Relevant articles and documents
New peroxy triterpenes from the aerial roots of Ficus microcarpa
Chiang, Yi-Ming,Kuo, Yueh-Hsiung
, p. 436 - 439 (2007/10/03)
Six new triterpenes, 3β-acetoxy-12β, 13β-epoxy-11α-hydroperoxyursane (1), 3β-acetoxy-11α-hydroperoxy-13αH-ursan-12-one (2), 3β-acetoxy-1β, 11α-epidioxy-12-ursene (3), (20S)-3β-acetoxylupan-29-oic acid (4), (20S)-3β-acetoxy-20-hydroperoxy-30-norlupane (5),
Biomimetic oxidation of 3β-hydroxy-olean-12-ene and its acetoxy derivative with monooxygen donors catalyzed by 5,10,15,20-tetraarylporphyrinatoiron(III) chlorides in dichloromethane
Chauhan,Mohapatra,Mamta,Parkash,Azam
, p. 183 - 189 (2007/10/03)
The oxidation of 3β-hydroxy-olean-12-ene with monooxygen donors catalyzed by 5,10,15,20-tetraarylporphyrinatoiron(III) chlorides in dichloromethane gives 3β,11α-dihydroxy-olean-12-ene, 3-oxo-olean-12-ene, 3,11-dioxo-olean-12-ene and 3β-hydroxy-olean-9(11),12-diene whereas the oxidation of 3β-acetoxy-olean-12-ene under similar conditions gives 11(-hydroxy-3β-acetoxy-olean-12-ene, 11-oxo-3β-acetoxy-olean-12-ene and 3β-acetoxy-olean-9(11),12-diene in moderate yields.
Oxidation of Terpenoid Compounds with tert-Butyl Chromate
Pinto, Angelo C.,Pereira, Anibal L.,Kelecom, Alphonse,Porreca, Lucia M.,Ribeiro, Nubia M.,Barnes, Roderick A.
, p. 4689 - 4692 (2007/10/02)
Oxidation with tert-butyl chromate of a methylene group adjacent to a double bond or aromatic ring has been effected in excellent yield with the majority of a selected group of diterpenes and triterpenes.Some of the factors influencing the course of the reaction are discussed.Keywords - oxidation; tert-butyl chromate; diterpene; triterpene; ketone
Functionalisation of Saturated Hydrocarbons. Part 6. Selective Oxidation of Steroids and Related Compounds
Barton, Derek H. R.,Boivin, Jean,Hill, Christopher H.
, p. 1797 - 1804 (2007/10/02)
The oxidation of a series of steroids by the Gif system gives, almost without exception, the 20-ketone as major isolated product.The side-chain cleavage is made more selective by modification of rings A or B.The oxidation of oleana-1,12-diene-3,11-dione has also been studied and the two principal products have been identified.
Phase-transfer Catalysed Allylic Oxidation of Hindered Double Bonds in a Rigid Framework by Sodium Periodate
Singh, Chandan
, p. 859 (2007/10/02)
The reaction of sodium periodate under phase-transfer catalysis with abietenol acetate-diethyl fumarate Diels-Alder adduct (1), β-amyrin acetate (3) and α-amyrin acetate (4) furnishes allylic oxygenated products 2, 5 and 6 respectively.This appears to be the first report of allylic oxidation by sodium periodate.
Phase-transfer Catalysed Oxidation with Chromic Trioxide: A Simple Procedure for Allylic Oxidation in α-Amyrin and β-Amyrin Series
Singh, Chandan
, p. 300 - 301 (2007/10/02)
Oxidation of α-amyrin acetate (3), β-amyrin acetate (1), ursolic acid acetate (5), hederagenin diacetate (7) and brahmic acid triacetate (9) by aqueous chromic trioxide in the presence of cetyltrimethylammonium bromide as phase-transfer catalyst in CCl4 furnishes the 11-oxo derivatives in more than 80percent yield.
A New Triterpene from Vellozia compacta
Barnes, Roderick A.,Pereira, Anibal L.,Scofield, Tereza Cristina V.,Filho, Raimundo Braz,Pinto, Angelo C.
, p. 3674 - 3677 (2007/10/02)
A triterpene not previously obtained from natural sources has been isolated from Vellozia compacta and its structure assigned on the basis of spectral data.For confirmation of this assignment, a partial synthesis was carried out. β-Amyrenyl acetate was oxidized and the resulting ketone reduced to a diol, which, after selective dehydration and reoxidation, furnished the natural product.Keywords - Vellozia compacta; Velloziaceae; triterpene; oleanane; partial synthesis.
Triterpenes of Diospyros peregrina Gurke: Partial Synthesis of Olean-9(11),12-dien-3-one and Ursan-9(11),12-dien-3-one (Marsformosanone)
Bhaumik, Tapanjyoti,Dey, A. K.,Das, P. C.,Mukhopadhyay, A. K.,Chatterjee, A.
, p. 664 - 668 (2007/10/02)
Petrol extract of the fruits of Diospyros peregrina (Ebenaceae) has afforded a pentacyclic triterpene ketone with a homoannular diene system, besides betulin and lupeol.In order to establish the structure of the ketone, partial synthesis of both olean- and ursan-9(11),12-dien-3-ones have been achieved.The structure of the pentacyclic triterpene ketone has been established as marsformosanone (II) from spectral data, chemical reactions and synthesis.The occurrence of marsformosanone in Marsdenia formosana Masamune has been recently reported .
Reactions of Some Triterpenes with Mercuric Acetate : An Unusual Reaction with Taraxeryl Acetate
Dasgupta, Asok,Goswami, A.,Ray, T. K.,Nath, A.,Khastgir, H. N.
, p. 165 - 168 (2007/10/02)
Reaction of mercuric acetate on three triterpenes has been studied.Both β- and α-amyrin acetates (I and II) undergo the expected oxidation to give α,β-unsaturated ketones (V) and (VI) respectively.Taraxeryl acetate (IIIb) undergoes elimination of acetoxy group with concomitant ring closure giving the hydrocarbon (IX).Retro-pinacol rearrangement of taraxerol (IIIa) affords the hydrocarbon (XVI).XVI has been isomerised into the thermodynamically more stable system (IX).A possible mechanism of formation of IX from IIIb is proposed.
TERPENOIDS OF CANARIUM ZEYLANICUM
Bandaranayake, Wickramasinghe M.
, p. 255 - 258 (2007/10/02)
The following terpenoids were identified in the oleoresin, bark and timber of Canarium zeylanicum: 3β-hydroxyurs-12-en-11-one, 3β-hydroxyolean-12-en-11-one, olean-12-en-3,11-dione, urs-12-en-3,11-dione, α- and β-amyrin, α- and β-amyrenone, taraxerol, sitosterol, canaric acid, elemene, elemol, α-pinene, α- and β-phellandrene, limonene, terpineol, and cavrone. - Key Word Index - Canarium zeylanicum; Burseraceae; oleoresin; bark; timber; monoterpenoids; sesquiterpenoids; triterpenoids; 3β-hydroxyurs-12-en-11-one (neoilexonol); 3β-hydroxyolean-12-en-11-one; olean-12-en-3,11-dione; urs-12-en-3,11-dione; elemene; elemol; α-amyrine and β-amyrine; α- and β-amyrenone; canaric acid; taraxerol; sitosterol.
