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1.
Three new sesquiterpenoids, metachromins R--T (1--3), have been isolated from an Okinawan marine sponge Spongia sp. The structures and stereochemistry of 1--3 were elucidated on the basis of the spectroscopic data. Metachromins S (2) and T (3) showed modest cytotoxicity.  相似文献   

2.
A new aromadendrane-type sesquiterpenoid, 4(15)-aromadendren-12,5alpha-olide and an aromadendrane-guaianolide dimer have been isolated from the New Zealand liverwort Chiloscyphus subporosus. Their structures were established by extensive NMR techniques and X-ray crystallographic analysis.  相似文献   

3.
Abstract

Chemical investigation of the aerial parts of Mikania micrantha led to the isolation of eight sesquiterpenoids and ten diterpenoids, including five cadinane sesquiterpenoids (1?5), three bisabolene sesquiterpenoids (6???8), nine ent-kaurane diterpenoids (917), and an abietane diterpenoid (18). Among them, 1???3 are new and feature a rare lactone or furan ring derived from C-6 isopropyl group side chain. Compound 18 was isolated from genus Mikania for the first time, and was also the first example of abietane-type diterpenoids from this plant. Their structures were elucidated on the basis of extensive spectroscopic analyses (1D and 2D NMR, HRESIMS, and ECD). All compounds were examined for their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 macrophage cells, and compound 18 exhibited pronounced inhibition on NO production (IC50 = 11.04?µM), being comparable to the positive control, quercetin (IC50 = 11.15?µM).  相似文献   

4.
The structures of four new sesquiterpenoids from the oleoresin ofAbies alba have been studied. On the basis of various spectral characteristics, the structures of (10S, 11S)-himachala-2,4-diene, (10S, 11S)-himachala-3(12), 4-diene, humula-4,9-dien-8-ol, and (4S, 5S, 10S)-selina-6-en-4-ol have been proposed for the compounds isolated. The stereochemistry of the asymmetric centers was determined by the conversion of these compounds into known sesquiterpenes and also by analysis of PMR spectra with a shift reagent.Novosibirsk Institute of Organic Chemistry, Siberian Branch, USSR Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 712–718, September–October, 1988.  相似文献   

5.
On the basis of chemical and physico-chemical evidence, structure 3 has been assigned to axisonitrile-2, a new sesquiterpenoid isonitrile from the marine sponge Axinella cannabina.  相似文献   

6.
A new dimeric sesquiterpenoid with two eudesmane skeletons through a urea linkage, halichonadin A (1), as well as three new eudesmane sesquiterpenoids having a carbamate, an isonitrile, or an amino functionality, halichonadins B (2), C (3), and D (4), respectively, have been isolated from a marine sponge Halichondria sp., and the gross structures and relative stereochemistry of 1-4 were elucidated on the basis of spectral data and chemical means.  相似文献   

7.
Two new structurally unique dimeric sesquiterpenoids, halichonadins K (1) and L (2), were isolated from an Okinawan marine sponge Halichondria sp. The structures of 1 and 2 were elucidated on the basis of spectroscopic analysis including a single crystal X-ray diffraction analysis and chemical conversion. Halichonadins K (1) and L (2) are homodimers of the eudesmane sesquiterpene linked with a piperidine ring through amide bonds. Halichonadin K (1) showed moderate cytotoxicity against KB cells.  相似文献   

8.
Three new dimeric sesquiterpenoids, halichonadins G-I (1-3), and one new eudesmane sesquiterpenoid possessing a 1-phenethyl urea moiety, halichonadin J (4), were isolated from a marine sponge Halichondria sp. Halichonadins G (1) and H (2) are homo-dimers of eudesmane sesquiterpenoid, linked through a methyl 2-{1-(2-amino-2-oxoethyl)ureido}acetate fragment and a 2-hydroxymalonamide fragment, respectively, while halichonadin I (3) is a new hetero-dimer of eudesmane sesquiterpenoid linked through a urea fragment. The structures of 1-4 were elucidated on the basis of spectroscopic data.  相似文献   

9.
Two new bazzanane-type sesquiterpenoids have been isolated from the New Zealand liverwort Frullania falciloba. Their structures were confirmed by NMR and CD spectroscopy and chemical reactivity.  相似文献   

10.
11.
Three Novel sesquiterpenoids have been isolated from the Okinawan see sponge Theonella cf. swinhoei and the structures have been determined on the basis of the spectral data and chemical reactions.  相似文献   

12.
The marine sponge Dysidea avara contained avarol (1) and avarone (2). Avarol on acylation yielded 2',5'-O-dibenzoylavarol (3); 2,5'-O-(4-chlorobenzoyl)avarol (4); 2,5'-O-dicinnamoylavarol (5); 2,5'-O-(4-bromobenzoyl)avarol(6); 2',5'-O-dioctanoylavarol (7); 2',5'-O-(4-fluorobenzoyl)avarol (8) and diacetylavarol (9). The structural elucidation of all the compounds 1-9 have been done by spectral analysis. The cytotoxicity of these compounds were also determined and evaluated. Compounds 6 and 9 showed selective cytotoxicity against Hepa (human hepatoma) and KB cell lines respectively.  相似文献   

13.
Two new tetrahydropyrans have been isolated from the sponge Haliclona sp. From chemical and spectroscopic evidence they are shown to be (1′R, 2S, 2″E, 5R, 6R)-2-(1′-bromethyl)-2,5-dimethyl-6-(penta-2″,4″-dienyl)-tetrahydropyran and (1′R, 2S, 5R, 6R)-2-(1′-bromoethyl)-2,5-dimethyl-6-(pent-4″-enyl)-tetrahydropyran.  相似文献   

14.
Two diterpenes, epipolone (1) and epipolol (3), produced by terpenoid pathways leading to a tricarbocyclic structure with an irregular "head to tail" isoprene configuration, have been isolated from the Caribbean marine sponge Epipolasis reiswigi collected in Puerto Rico. The structures of 1 and 3 were elucidated largely by 1D and 2D NMR methods and chemical conversion.  相似文献   

15.
Six new diterpene isocyanides have been isolated from a sponge (Adocia sp.). Their structures support the biosynthetic suggestion for the formation of diisocyanoadociane reported from the same sponge.  相似文献   

16.
17.
The methanol extract of the sponge Spongia officinalis from Pt. Guimar, Tenerife (Canary Islands) contained new diterpenoids which inhibited the growth of microbes. The structures of the new diterpenes isolated were determined as; 11β-hydroxyspongi-12-en-16-one (2), 11β-acetoxyspongi-12-en-16-one (3), 7β,11β-dihydroxy8pongi-12-en-16-one (5), and 7β,11α-dihydroxy-spongi-12-en-16-one (6), by spectral and chemical degradation studies. The previously reported diterpenes isoagatholactone (1) and aplysillin (4) were also found in the extract.  相似文献   

18.
Three new sulfated meroterpenoids containing sesquiterpene and hydroquinone moieties, namely siphonodictyal A sulfate (1), akadisulfate A (2) and akadisulfate B (3), along with the known siphonodictyal B3 and bis(sulfato)-cyclosiphonodictyol A were isolated from the sponge Aka coralliphaga. Their structures were elucidated on the basis of spectroscopic data. Akadisulfate B and siphonodictyal B3 showed a radical-scavenging activity comparable with that of the known lipophylic antioxidant BHT.  相似文献   

19.
This review covers the structures and biological activities of eudesmane-type sesquiterpenoids from the plants of the Asteraceae family. Biosynthetic studies or chemical syntheses leading to the revision of structures or stereochemistries have also been included, and 593 references are cited.  相似文献   

20.
G. Cimino  S. De Stefano  L. Minale 《Tetrahedron》1973,29(17):2565-2570
Five new substances, panicein-A, -B1, -B2, -B3 and C, containing an aromatic sesquiterpenoid moiety linked to a quinol or a quinone system, have been isolated from the sponge Halichondria panicea. The structures of these compounds were elucidated from their chemical and spectral properties.  相似文献   

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