514-07-8Relevant academic research and scientific papers
Taraxer-14-en-3β-ol, an Anti-Inflammatory Compound from Sterculia foetida L.
Naik,Mujumdar,Waghole,Misar,Annie Bligh,Bashall, Alan,Crowder, John
, p. 68 - 69 (2007/10/03)
Taraxer-14-en-3β-ol (1) was shown to be the active ingredient in the leaves of Sterculia foetida L. The alcohol 1, its acetate and ketone showed anti-inflammatory activity against TPA induced mouse ear oedema with inhibition ratios of 60.0, 58.57 and 40.57 at 0.5 mg/ear, respectively. The percentage inhibition of inflammation increased with dose for each compound.
Oxidative deprotection of oximes, phenylhydrazones and semicarbazones using pyridinium chlorochromate in catalytic amount with t-butyl hydroperoxide and in the solid state on montmorillonite K-10 clay support under microwave irradiation
Ganguly, Nemai C.,Datta, Mrityunjoy,De, Prithwiraj
, p. 308 - 312 (2007/10/03)
Pyridinium chlorochromate (FCC) and other oxochromium(VI) reagents have been extensively employed in excess of the stoichiometric amount (2 equivalents or more) for efficient cleavage of oximes to carbonyl compounds. The aim of this study is to replace excess use of toxic chromium(VI) reagents and develop cleaner environment-friendly general methods of cleavage of imine derivatives such as oximes, phenylhydrazones and semicarbazones using PCC in catalytic or stoichiometric amount. Two approaches of greening the deprotection process with PCC are conceived of which the first one is based on the catalytic use of the reagent (0.1 equiv.) in combination with an excess of 70% t-butyl hydroperoxide as the cooxidant. Mild selective regeneration of carbonyl compounds from oximes, phenylhydrazones and semicarbazones has been accomplished in good-to-excellent yields (70-98%) by this method. With focus on rate enhancement coupled with efficiency of cleavage, an alternative microwave-assisted solid-state solventiess protocol of deprotection employing a stoichiometric amount of PCC dispersed on montmorillonite K-10 clay is also evaluated. It offers an expeditious efficient (74-98% yields) general route of cleavage of these procarbonyl compounds. Absence of overoxidation, particularly for oxidation-prone aryl aldehydes, is the key advantage of both these methods.
Triterpenes from the Leaves of Parsonsia Laevigata
Ogihara, Kazuhito,Higa, Matsutake,Hokama, Kozo,Suga, Takayuki
, p. 783 - 786 (2007/10/02)
A novel taraxerane-type triterpene-diol, in addition to taraxerol and lupeol, was isolated from the leaves of Parsonsia laevigata.Its structure was shown to be (4β)-D-friedoolean-14-ene-3β,24-diol (taraxer-14-ene-3β,24-diol) by a combination of chemical and spectroscopic methods.Key Word Index - Parsonsia laevigata; Apocynaceae; taraxerane-type triterpenoid; (4β)-D-friedoolean-14-ene-3β,24-diol.
Triterpenoids of the Bark of Pieris japonica D. Don (Japenese Name: Asebi). II. 13C Nuclear Magnetic Resonance of the γ-Lactones of Ursane- and Oleane-type Triterpenes
Katai, Masaaki,Terai, Tadamasa,Meguri, Haruo
, p. 1567 - 1571 (2007/10/02)
Eight triterpenoids and a sterol were isolated from the bark of Pieris japonica D.Don (Japenese name: asebi, Ericaceae) and have been elucidated as 3β-acetoxyurs-11-en-28,13-olide, 3β-acetoxy-12α-hydroxyolean-28,13-olide, 3β-acetoxy-28-hydroxyurs-12-ene, 3β,28-dihydroxyurs-12-ene, 3β-acetoxyurs-12-en-28-al, taraxeryl-acetate, taraxerol, taraxerone and β-sitosterone by a combination of chemical and spectroscopic studies. 13C Nuclear magnetic resonance spectral analysis of several γ-lactones of the ursane and oleanane series was undertaken, and all the carbons were assigned by means of single frequency off-resonance and selective decoupling methods and by comparison of the signals with those of methyl esters of acetyl ursolic acid and acetyl oleanolic acid.Keywords - Pieris japonica; bark; triterpenoid; ursane-type γ-lactone; oleanane-type γ-lactone; 1H-NMR; 13C-NMR
