- Purification and properties of squalene-2,3-epoxide cyclases from pea seedlings
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Dramatic changes in the activities of squalene-2,3-epoxide: cycloartenol cyclase and β-amyrin cyclase were observed in germinating pea seeds. By taking advantage of this phenomenon, the two cyclases were purified from pea seedlings. The cyclases were purified to homogeneity by solubilization with Triton X-100, chromatography on hydroxylapatite and diethylaminoethyl (DEAE)-cellulose, isoelectric focusing and gel filtration. Cycloartenol cyclase was purified 471-fold to a specific activity of 167 pkat/mg protein, while β-amyrin cyclase was purified 4290-fold to a specific activity of 28 pkat/mg protein. They each showed a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis with a molecular mass of 55 and 35 kilodaltons (kDa), respectively. The apparent K(m) values for (3S)-squalene-2,3-epoxide were estimated to be 25 and 50 μm, respectively. The cyclases required Triton X-100 or deoxycholate for their highest activity and each showed a broad pH optimum within the range of pH 6.5-7.5. Inhibition by p-chloromercuribenzene sulfonic acid and N-ethylmaleimide suggested involvement of an SH group at the active site of each enzyme.
- Abe,Sankawa,Ebizuka
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- COMPOSITIONS COMPRISING TRITERPENOIDS AND USES THEREOF FOR TREATING OPTIC NEUROPATHY
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The invention relates to compositions and formulations comprising at least one triterpenoic acid and at least one neutral triterpenoid and uses thereof for treating optic neuropathy conditions.
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- An improved scalable synthesis of α- and β-amyrin
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The synthesis of α- and β-amyrin was accomplished starting from easily accessible starting materials, oleanolic, and ursolic acid. The procedures allow the preparation of β-amyrin in an exceptionally short scalable manner via selective iodation and reduction. For α-amyrin, a different synthetic approach had to be chosen providing access to α-amyrin in medium-to-large scale.
- Serbian, Immo,Csuk, René
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- COMPOSITIONS COMPRISING TRITERPENOIDS
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The invention relates to compositions and formulations comprising at least one triterpenoic acid and at least one neutral triterpenoid and uses thereof for treating for use in treating a condition selected from Alzheimer's disease (AD), Parkinson's Diseases (PD) and vascular dementia (VD).
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Page/Page column 88; 89; 90
(2017/04/11)
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- Practical Synthesis of α-Amyrin, β-Amyrin, and Lupeol: The Potential Natural Inhibitors of Human Oxidosqualene Cyclase
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A practical synthesis of α-amyrin (1), β-amyrin (2), and lupeol (3) was accomplished in total yields of 32, 42, and 40% starting from easily available ursolic acid (4), oleanolic acid (5), and betulin (6), respectively. Remarkably, these three natural pentacyclic triterpenes exhibited potential inhibitory activity against human oxidosqualene cyclase.
- Chen, Dongyin,Xu, Fengguo,Zhang, Pu,Deng, Jie,Sun, Hongbin,Wen, Xiaoan,Liu, Jun
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- β-Amyrin Biosynthesis: Promiscuity for Steric Bulk at Position 23 in the Oxidosqualene Substrate and the Significance of Hydrophobic Interaction between the Methyl Group at Position 30 and the Binding Site
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To examine how the sterics at the 23 position of (3S)-2,3-oxidosqualene 1 influence the polycyclization cascade in β-amyrin biosynthesis, substrate analogues substituted with an ethyl group (10, 11), a hydrogen atom (12, 13), or a propyl residue (14) at the 23 position were incubated with β-amyrin synthase. The bulkier ethyl group was accepted as a substrate, leading to formation of the β-amyrin skeleton (42, 43) without truncation of the multiple cyclization reactions. Analogue 13, possessing a hydrogen atom and an ethyl group at the 23E and 23Z positions, respectively, was also converted into the β-amyrin skeleton 45. However, the analogue lacking an ethyl group at the 23Z position (12) underwent almost no conversion, strongly indicating that an alkyl group must exist at the Z position. The cyclization of the analogue with a propyl substituent at the Z position (14) was poor. Analogue 15 possessing CH2OH at the 23E position afforded a new compound 47 in a high yield as a result of trapping of the final oleanyl cation. Conversely, 16 with 23Z-CH2OH afforded novel compounds 48-50 in low yields, which resulted from the intermediary dammarenyl and baccharenyl cations. Therefore, the hydrophobic interaction between the 23Z-alkyl group and its binding site (possibly via CH/π interaction) is critical for adopting the correct chair-chair-chair-boat-boat conformation and for the full cyclization cascade.
- Kaneko, Ikki,Hoshino, Tsutomu
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p. 6657 - 6671
(2016/08/16)
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- Triterpene esters: Natural products from dorstenia arifolia (moraceae)
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The phytochemical study of Dorstenia arifolia Lam. (Moraceae) has led to the identification of 18 triterpenes esterified by fatty acids, five triterpenes without esterification, 12 triterpenes esterified by acetic acid, together with a known furanocoumarin: α-amyrin (1), β-amyrin (2) α-amyrin acetate (3) β-amyrin acetate (4), α-amyrin octanoate (5), β-amyrin octanoate (6), α-amyrin decanoate (7), β-amyrin decanoate (8), α-amyrin dodecanoate (9), β-amyrin dodecanoate (10), α-amyrin tetradecanoate (11), β-amyrin tetradecanoate (12), α-amyrin hexadecanoate (13), β-amyrin hexadecanoate (14), glutinol (15), glutinyl acetate (16), 11-oxo-α-amyrin (17), 11-oxo-β-amyrin (18), 11-oxo-α-amyrin acetate (19), 11-oxo- β-amyrin acetate (20) 11-oxo-α-amyrin octanoate (21) 11-oxo-β-amyrin octanoate (22), 11-oxo-α-amyrin decanoate (23), 11-oxo-β-amyrin decanoate (24) 11-oxo-α-amyrin dodecanoate (25) 11-oxo-β-amyrin dodecanoate (26), ursa-9(11),12-dien-3-yl acetate (27), oleana-9(11),12-dien-3-yl acetate (28), ursa-9(11),12-dien-3-yl decanoate (29), oleana- 9(11),12-dien-3-yl decanoate (30), 12,13-epoxyolean-3-yl acetate (31), 12,13-epoxyolean- 9(11)en-3-yl acetate (32), taraxeryl acetate (33), lupenyl acetate (34), lanosta-8,24-dien-3- yl acetate (35) and psoralen (36). The identification of the triterpene compounds isolated as isomeric mixtures obtained from the hexane extract was based mainly in mass spectra and 13C-NMR data. The long-chain alkanoic acid esters of the triterpenes α- and β-amyrin; 11-oxo-α- and 11-oxo-β-amyrin; ursa- and olean-9(11),12-dien-3-yl; have not been reported before in the literature as constituents of the Dorstenia genus.
- Fingolo, Catharina E.,De S. Santos, Thabata,Filho, Marcelo D.M. Vianna,Kaplan, Maria Auxiliadora C.
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p. 4247 - 4256
(2013/06/05)
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- TRITERPENE OXIDASE DERIVED FROM PLANT BELONGING TO GENUS GLYCYRRHIZA, GENE ENCODING THE SAME, AND METHOD OF USING THE SAME
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Identification of a protein having an activity of oxidizing oleanane-type triterpene, and a gene encoding the protein, the protein and the gene, and use thereof are provided. For example, a protein having an activity of oxidizing oleanane-type triterpene obtained from a plant in the family Fabaceae, a gene encoding the protein and use thereof are provided. The protein is shown in, for example, SEQ ID NO: 4, 14 or 18, and the gene encoding the protein is shown in, for example, SEQ ID NO: 3, 13 or 17. A transformant into which the gene is introduced can be produced, and thereby a triterpene oxidase can be obtained.
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- Ethylenediamine: An effective reagent for deacetylation of natural products
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The use of ethylenediamine in methanol is described for the selective cleavage of the acetate group in nimbin (1) to 6-deacetyl nimbin (1a) under microwave irradiation. This method enables to deacetylate without affecting other functional groups such as ,α,β-unsaturated ketone, ester, ether, etc. in certain tetranortriterpenoids and other acetate-containing natural compounds.
- Mohankumar, Ramasamy,Ilango, Kaliappan,Santhanakrishnan, Vichangal Pridiuldi,Radhakrishnan, Viswanathan,Narasimhan, Srinivasan
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experimental part
p. 851 - 858
(2010/12/25)
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- New triterpenoids and other constituents from a special microbial-fermented tea - Fuzhuan brick tea
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Fuzhuan brick tea, a special microbial-fermented tea prepared from the leaves of Camellia sinensis var. sinensis, is a traditional beverage used in China throughout history. Phytochemical investigation of this material led to the identification of three new triterpenoids, 3 ,6α,13β- trihydroxyolean-7-one (1), 3β-acetoxy-6α,13β-dihydroxyolean-7- one (2), and 3β-O-(8-hydroxyoctanoyl)-12-oleanene (3), together with 11 known compounds, friedelin (4), β-amyrone (5), β-amyrin (6), α-spinasterone (7), α-spinasterol (8), 22,23-dihydro-α- spinasterone (9), 22,23-dihydro-α-spinasterol (10), α-phytol (11), α-tocopherol (12), α-tocoquinone (13), and caffeine (14). The structures of 1-13 were determined by spectroscopic and chemical methods. Compounds 1 and 2 are the first two examples of triterpenoids possessing a 6-hydroxy-7-one function. All of the compounds, except 6, 8, 10, 11, and 14, were isolated from tea and Camellia spp. for the first time. The antibacterial activities of 1 were assessed against some enteric pathogenic microbes. Compound 1 showed no cytotoxic activity against A-549, Bel-7402, and HCT-8 cell lines.
- Ling, Tie-Jun,Wan, Xiao-Chun,Ling, Wei-Wei,Zhang, Zheng-Zhu,Xia, Tao,Li, Da-Xiang,Hou, Ru-Yan
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experimental part
p. 4945 - 4950
(2011/08/03)
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- A short enantioselective total synthesis of the fundamental pentacyclic triterpene lupeol
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(Chemical Equation Presented) The first enantioselective synthesis of lupeol has been developed by applying two carefully crafted cation-π cyclization stages to generate the pentacyclic structure with complete stereocontrol. The synthesis (Scheme 1) is no
- Surendra, Karavadhi,Corey
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supporting information; experimental part
p. 13928 - 13929
(2009/12/25)
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- Arabidopsis camelliol C synthase evolved from enzymes that make pentacycles
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(Chemical Equation Presented) We establish by heterologous expression that the Arabidopsis thaliana oxidosqualene cyclase At1g78955 (CAMS1) makes camelliol C (98%), achilleol A (2%), and β-amyrin (0.2%). CAMS1 is the first characterized cyclase that generates predominantly a monocyclic triterpene alcohol. Phylogenese analysis shows that CAMS1 evolved from enzymes that make pentacycles, thus revealing that its pentacyclic β-amyrin byproduct is an evolutionary relic. Sequence alignments support prior suggestions that decreased steric bulk at a key active-site residue promotes monocycle formation.
- Kolesnikova, Mariya D.,Wilson, William K.,Lynch, David A.,Obermeyer, Allie C.,Matsuda, Seiichi P. T.
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p. 5223 - 5226
(2008/09/17)
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- Preventive effects of soyasapogenol B derivatives on liver injury in a concanavalin A-induced hepatitis model
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To shed light on the structure-activity relationship, various soyasapogenol B derivatives were synthesized and evaluated for preventive effects on liver injury in the concanavalin A (Con A)-induced hepatitis model in mice. Con A injection into mice induces some pathophysiology of human liver disease such as autoimmune or viral hepatitis. Two hydroxyl groups on the A ring of soyasapogenol B are required for amelioration of liver damage. Modification of the C-22 hydroxyl moiety with an acyloxy or alkyloxy group, or removal of the hydroxyl group, resulted in a greatly enhanced percentage of alleviation. Among the series of soyasapogenol B derivatives examined, six compounds exhibited preventive effects on liver damage.
- Sasaki, Kazue,Minowa, Nobuto,Kuzuhara, Hiroyuki,Nishiyama, Shoji
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p. 4900 - 4911
(2007/10/03)
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- Arabidopsis thaliana LUP1 converts oxidosqualene to multiple triterpene alcohols and a triterpene diol
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lupeol lupeol, germanicol, synthase β-amyrin, taxasterol, oxidosqualene → ψ-taraxasterol, and 3,20-dihydroxylupane The Arabidopsis thaliana LUP1 gene encodes an enzyme that converts oxidosqualene to pentacyclic triterpenes. Lupeol and β-amyrin were previously reported as LUP1 products. Further investigation described here uncovered the additional products germanicol, taraxasterol, ψ-taraxasterol, and 3,20-dihydroxylupane. These results suggest that the 80 known C30H50O compounds that are structurally consistent with being oxidosqualene cyclase products may be derived from fewer than 80 enzymes and that some C30H52O2 compounds may be direct cyclization products of oxidosqualene.
- Segura, Michael J. R.,Meyer, Michelle M.,Matsuda, Seiichi P. T.
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p. 2257 - 2259
(2007/10/03)
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- An antidepressant principle of Lobelia inflata L. (Campanulaceae)
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A crude methanolic extract of the leaves of Lobelia inflata exhibited antidepressant activity in mice. The extract was fractionated, monitored by the activity, to give β-amyrin palmitate as an active component.
- Subarnas,Oshima,Sidik,Ohizumi
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p. 620 - 621
(2007/10/02)
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- TRITERPENE DIENOLS AND OTHER CONSTITUENTS FROM THE BARK OF PHYLLANTHUS FLEXUOSUS
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Phyllanthus flexuosus; Euphorbiaceae; stem bark; n-alkane derivatives; ent-3β-hydroxykaur-16-ene; triterpenes; oleanadienols; phytosterols; bergenin.Besides four known triterpenes and bergenin, ent-3β-hydroxykaur-16-ene and two oleanedienols were isolated from the stem bark of Phyllanthus flexuosus.The bark also contained n-alkanes, n-alkanols and phytosterols.
- Tanaka, Reiko,Matsunaga, Shunyo
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p. 2273 - 2278
(2007/10/02)
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- REDUCTION OF KETONES TO EPIMERIC ALCOHOLS WITH POTASSIUM HYDROXIDE-DIETHYLENE GLYCOL
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Triterpenoid ketones have been reduced to epimeric alcohols on boiling with potassium hydroxide in diethylene glycol. α,β-unsaturated ketone furnished saturated epimeric alcohols.
- Pradhan, B. P.,Hassan, A.,Ray, T.
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p. 2513 - 2516
(2007/10/02)
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- Lithium-Ethylenediamine as a Reducing Agent
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In a series of triterpenoids, ketones have been converted into sterically more stable secondary alcohols, aldehydes to primary alcohols, hindered esters to acids and isopropenyl groups to isopropyl groups on reduction with lithium in ethylenediamine in high yields.
- Pradhan, Bhim Prasad,Chakrabarti, Dilip Kumar,Chakraborty, Satyajit
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p. 1115 - 1116
(2007/10/02)
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