共查询到20条相似文献,搜索用时 15 毫秒
1.
A study has been made of the principal rearrangement products resulting from formic acid treatment of 19-hydroxy-ent-beyerene epoxide (3). In concentrated solutions 3 has been found to undergo a deep seated rearrangement to the allylic alcohol (14). A mechanism for the formation of 14 is proposed involving a novel 1,4-hydride shift in the bicyclo[3:2:1]octane C/D ring system following cleavage of the C15O bond. Supporting evidence has been obtained from a study of the specifically labelled epoxide (4), the deuterium in 14 appearing exclusively at C12. Four products (7 and 11–13) emanating from the known beyerane → kaurane interconversion have been identified. 相似文献
2.
V. L. Mamedova D. R. Sharafutdinova K. A. Nikitina T. P. Gerasimova O. B. Bazanova V. A. Al’fonsov 《Russian Journal of General Chemistry》2014,84(4):700-703
Metal salts (including transition metals salts) of chiral natural diterpenoid isosteviol and its hydrophosphoryl derivative were obtained for the first time. The compounds obtained can be used in pharmaceutics, metal catalysis, and also for creating new materials with magnetic properties. 相似文献
3.
Proposed biogenesis of diterpenoid alkaloids 总被引:2,自引:0,他引:2
Literature information is generalized and an analysis is made of investigations relating to the biogenesis of diterpene alkaloids.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 337–354, May–June, 1995. Original article submitted May 18, 1993. 相似文献
4.
V.Nambi Aiyar Penelope W. Codding K.Ann Kerr M.H. Benn Alan J. Jones 《Tetrahedron letters》1981,22(6):483-484
The structure of delphinifoline, a minor alkaloid of DC, was established by spectroscopic methods, and X-ray crystallography. 相似文献
5.
Salei L. A. Popa D. P. Doleish L. Lazur'evskii G. V. 《Chemistry of Natural Compounds》1967,3(2):75-78
Chemistry of Natural Compounds - On the basis of chemical and spectroscopic data, the diterpene alcohol peregrinol has been assigned the structure 13-labdene-9, 15-diol. 相似文献
6.
7.
This paper presents the first successful total synthesis of pikrosalvin, a compound naturally derived from Salvia officinalis, grounded on the structural framework delineated by Brieskorn and Fuchs. Our synthetic approach was underpinned by a biomimetic strategy inspired by the Stork–Eschenmoser hypothesis for the biosynthesis of terpenes via polyene cyclization. Starting with commercially available vanillic acid and geraniol, we strategically assembled pikrosalvin's structural core, consisting of a decalin A/B ring, an aromatic C ring, and a butyrolactone D ring. Challenges related to protective groups and specific catalytic conditions were effectively addressed, resulting in high product yields. We further demonstrated the efficacy and broad applicability of a combined-acid-catalyzed polyene cyclization methodology in the context of complex natural product synthesis. This study sets the stage for future biological and pharmacological investigations of pikrosalvin. 相似文献
8.
New diterpenoid glucosides from Siegesbeckia pubescens 总被引:5,自引:0,他引:5
Jiang XIONG Qi Duan JIN Yun Long XU* Kunming Institute of Botany The Chinese Academy of Sciences Kunming 《中国化学快报》2001,(1)
Plants of the genus Siegesbeckia are annual herbs widely distributed in tropical and temperate zones and they are used as a traditional medicine to treat rheumatic arthritis, hypertension, malaria, neurasthenia and snake-bite in China. In previous papers, we reported on five new ent-kaurane and ent-pimarane diterpenoids, siegesbeckioside, siegesbeckiol and siegesbeckic acid1, orientalin A and B, and eight know compounds2,3. The present paper describes the isolation and structural elucidation … 相似文献
9.
M. S. Yunusov 《Russian Chemical Bulletin》2011,60(4):633-638
Diterpenoid alkaloids comprise a large group of natural compounds produced by the plants of the genera Aconitum and Delphinium.
Some of these compounds were found to manifest valuable pharmacological properties, including the unique antiarrhythmic activity.
Allapinine (derived from the alkaloid lappaconitine) was approved as a drug. The investigation of the structure—activity relationship
revealed structural elements responsible for the arrhythmogenic and antiarrhythmic properties. 相似文献
10.
<正>A new jatrophane-type diterpenoid,7β,14β,15β-triacetoxy-3β-benzoyloxy-9-oxojatropha-5E,11E-diene,named euphornin N was isolated from Euphorbia helioscopia L.The structure and relative stereochemistry of the new compound was elucidated by spectroscopic methods. 相似文献
11.
Zinurova E. G. Kabal"nova N. N. Shereshovets V. V. Ivanova E. V. Shults E. E. Tolstikov G. A. Yunusov M. S. 《Russian Chemical Bulletin》2001,50(4):720-723
Oxidation of diterpene alkaloids by dimethyldioxirane was studied with eldeline, talatizamine, aconitine, and zongorine as examples. Nitrones and 19-oxo derivatives of bases were obtained. The results of the oxidation allow one to draw an analogy with the oxidation by KMnO4 and to suggest a mechanism of the reaction. 相似文献
12.
Hiroaki Miyaoka Tomohiro Baba Hidemichi Mitome Yasuji Yamada 《Tetrahedron letters》2001,42(52):9233-9236
Marine dolabellane diterpenoid stolonidiol was synthesized from l-ascorbic acid. The method for this total synthesis involves formation of the bicyclo[2.2.1]heptane derivative using a diastereoselective sequential Michael reaction, formation of cyclopentane derivative by the retro-aldol reaction and construction of an 11-membered carbocyclic ring through the intramolecular Horner–Wadsworth–Emmons reaction. 相似文献
13.
Study of the low and high-resolution mass spectra of a series of diterpenoid acetals, including both positional isomers and stereoisomers, has permitted the proposal of some characteristic fragmentation pathways leading to analytically distinctive peaks. The mass spectrum was particularly informative in the assignment of structure to an unexpected rearrangement product (V). 相似文献
14.
15.
16.
17.
Kabir S Rahman MS Chowdhury AM Hasan CM Rashid MA 《Natural product communications》2010,5(10):1543-1546
The stem bark of Polyalthia simiarum has yielded a new bisnor-type clerodane diterpenoid, 2-oxo-14,15-bisnor-3,11E-kolavadien-13-one (1), and three previously known clerodane derivatives, kolavenic acid (2), 16beta-hydroxycleroda-3,13(14)Z-dien-15,16-olide (3), and 16-oxocleroda-3,13(14)E-dien-15-oic acid (4). The structures of these compounds were unambiguously determined by extensive NMR studies as well as by comparison with related compounds. Till now this is the second report of the occurrence of any unusual C-18 clerodane diterpenoid from nature. The crude light petroleum extract and the purified compound 3 demonstrated moderate free radical scavenging activity with IC50 values of 21.5 and 23.5 microg/mL, respectively. 相似文献
18.
<正>A new ent-labdane diterpenoid,19-O-β-D-glucopyranosyl-ent-labda-8(17),13-dien-15,16,19-triol,together with six known ent-labdane diterpenoids,was isolated from the aerial parts of Andrographis paniculaia.The structure of the new compound was elucidated by extensive spectral analysis. 相似文献
19.
20.
Chen-Liang Chao Hui-Chi Huang Hsiou-Yu Ding Jenn-Haung Lai Hang-Ching Lin 《Natural product research》2020,34(19):2737-2745
AbstractA new macrocyclic diterpenoid, 4β,5β-dihydroxyovatodiolide (1), together with twenty-two known compounds (2-23) were isolated from the MeOH extract of the dried aerial parts of Anisomeles indica (L.) O. Kuntze (Labiatae). The structure of 1 was established on the basis of spectral evidence. Phenylethanoids, acteoside (5) and isoacteoside (6) showed significant inhibitory to IL-2 secretion of with respect to phorbol myristate acetate and anti-CD28 monoclonal antibody co-stimulated activation of human peripheral blood T cells. 相似文献