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1.
Seeds ofFatsia japonica(Araliaceae) afforded the known hederagenin 3-O--D-glucopyranosyl-(12)-O--L-arabinopyranoside and the new triterpene glycoside D 2 , for which the structure hederagenin 3-O--D- galactopyranosyl-(12)-O--L-arabinopyranoside was proposed based on chemical methods and NMR spectroscopy  相似文献   

2.
Seeds of Fatsia japonica (Araliaceae) yielded the new glycosides of gypsogenin: 3-O--D-glucopyranosyl-(12)-O--D-glucopyranoside and 3-O--D-galactopyranosyl-(12)-O--D-glucopyranoside. The structures of these compounds were established by chemical methods and NMR spectroscopy.  相似文献   

3.
Roots of Tragacantha stipulosa Boriss yielded three triterpene glycosides of the cycloartane series: askendoside G (1), askendoside D (2), and cycloglobiceposide B (3). Glycoside 1 is 3-O--L-arabinopyranosyl-(12)--D-xylopyranoside; 16-O--D-glucopyranoside-24R-cycloartan-3,6,16,24,25-pentaol; 2 - 3-O--L-arabinopyranosyl-(12)--D-xylopyranoside; 6-O--D-xylopyranoside-20R,24S-epoxycycloartan-3,6,16,25-tetraol; 3 - 3-O--D-xylopyranoside; 16-O--D-glucopyranoside; 25-O--D-glucopyranoside-24R-cycloartan-3,6,16,24,25-pentaol.  相似文献   

4.
5.
The new cycloartane glycoside cyclogaleginoside E, 20S,24R-cycloartan-3,6,16,25-tetraol-3-O--D-xylopyranoside-25-O--D-glucopyranoside, was isolated from stems of Astragalus galegiformis L. Its structure was established using enzymatic and total acid hydrolysis, mass spectrometry, and PMR and 13C NMR.  相似文献   

6.
Orbicoside, a new lanostane glycoside and the first from plants of the Astragalus genus, was isolated from the aerial organs of Astragalus orbiculatus Ledeb. (Leguminosae). It has the structure 23,24-lanost-9(11)-en- 3,7,16,19,23,24,25-heptaol 3-O--D-xylopyranoside. The structure of orbicoside was established using PMR and 13C NMR, which were interpreted using DEPT and 2D NMR spectroscopies 1H-1H COSY, HSQC, and HMBC.  相似文献   

7.
The new lanostane methylsteroid orbigenin, the structure of which is 23,24-lanost-9(11)-en-3,7,16,19,23,24,25-heptaol, was isolated from Astragalus orbiculatus Ledeb. (Leguminosae). The structure of the new triterpenoid, the first lanostanoid from plants of the Astragalus genus, was determined using electron-impact mass spectrometry and PMR and 13C NMR spectroscopies interpreted using J-modulation, DEPT, and the 2D NMR methods: 1H-1H COSY, HSQC, and HMBC.  相似文献   

8.
Two new triterpenoid glycosides, together with two new ergostane glycosides, umbellatosides A–D ( 1 – 4 , resp.), have been isolated from the leaves of Hydrocotyle umbellata L. Their structures were established by 2D‐NMR spectroscopic techniques (1H,1H‐COSY, TOCSY, NOESY, HSQC, and HMBC) and mass spectrometry as 3β,22β‐dihydroxy‐3‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucuronopyranosyl]olean‐12‐en‐28‐oic acid 28‐Oβ‐D ‐glucopyranosyl ester ( 1 ), 3‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucuronopyranosyl]oleanolic acid 28‐Oβ‐D ‐glucopyranosyl ester ( 2 ), (3β,11α,26)‐ergosta‐5,24(28)‐diene‐3,11,26‐triol 3‐O‐(β‐D ‐glucopyranosyl)‐11‐O‐(α‐L ‐rhamnopyranosyl)‐26‐Oβ‐D ‐glucopyranoside ( 3 ), and (3β,11α,21,26)‐ergosta‐5,24(28)‐diene‐3,11,21,26‐tetrol 3‐O‐(β‐D ‐glucopyranosyl)‐11‐O‐(α‐L ‐rhamnopyranosyl)‐26‐Oβ‐D ‐glucopyranoside ( 4 ).  相似文献   

9.
Novel dialkylphosphonates of arteannuin B were synthesized in 45-47% yields by reaction of this cadinanolide with dialkylphosphites. Their structures were established using IR, PMR, 13C and 31P NMR spectroscopy, and two-dimensional 1H-1H NMR (COSY) spectroscopy. The reaction of arteannuin B and dialkylphosphites is highly stereoselective.  相似文献   

10.
The new cycloartane glycoside cycloorbicoside D, which has the structure 23ξ,24ξ-cycloartan-3β6α,16β,23,24,25-hexaol 3-O-β-D-xylopyranoside, was isolated from the aerial part of Astragalus orbiculatus Ledeb. (Leguminosae). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 345–346, July–August, 2005.  相似文献   

11.
Crystalline taraxasterol and its acetate were isolated for the first time from Onopordum acanthium. Two-dimensional COSY, HSQC, and HMBC NMR experimentswere carried out forcomplete assignment of signals in the PMR and 13C NMR. Chemical shifts of stereochemically important methyl C atoms C-28 and C-29 were measured.  相似文献   

12.
The structures of colorless, red, and yellow-orange fluorescein have been investigated by a combination of solution and solid state13C NMR. It is demonstrated that the three forms have lactonic, zwitterionic, and quinoid structures, respectively. Conflicting X-ray, NMR, and IR structural evidence is discussed for samples of red fluorescein which cannot readily be obtained in definite crystalline form. It is concluded that solid-state13C NMR spectroscopy is superior by revealing primarily the molecular structure but being fairly insensitive toward lattice variations.The Editors regret the long delay in having this paper printed due to an unfortunate administrative error.  相似文献   

13.
Structures of 13 new acetylated triterpene glycosides from leaves of Cussonia paniculata (Araliaceae) were established as 28-O-(2-O-acetyl- and 3-O-acetyl-α-L-rhamnopyranosyl)-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β -D-glucopyranosides of 23-hydroxybetulinic acid (1a and 1b) and hederagenin (2a and 2b), 3-O-α-L-arabinopyranosyl-28-O-(2-O-acetyl- and 3-O-acetyl-a-L-rhamnopyranosyl)-(1→ 4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glycopyranosides of oleanic (3a and 3b) and ursolic (3c and 3d) acids, 3-O-α-L-arabinopyranosyl-28-O-(4-O-acetyl-, 2-O-acetyl-, and 3-O-acetyl-α-L-rhamnopyranosyl)-(1→4)-O-β-D-glucopyranosyl-(1→ 6)-O-β-D-glucopyranosides of hederagenin (4, d5a and 5b), and 3-O-β-D-glucopyranosyl-(1→2)-O-α-L-arabinopyranosyl-28-O-(2-O-acetyl- and 3-O-acetyl-α-L-rhamnopyranosyl)-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D- glucopyranosides of oleanic acid (6a and 6b). The structures of the compounds were established using chemical methods and NMR spectroscopy. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 351–356, July–August, 2005.  相似文献   

14.
Nine compounds including six cycloartane glycosides cyclosieversiosides A, B, F, G, and H and astrasieversianin IX; β-sitosterol, β-sitosterol β-D-glucopyranoside, and D-3-O-methyl-chiro-inositol were isolated and identified from roots of Astragalus sieversianus Pall. (Leguminosae) growing in the Republic of Kyrgyzstan. Presented at the 6th International Symposium on the Chemistry of Natural Compounds (SCNC, Ankara, Turkey, June 28–29, 2005. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 253–256, May–June, 2008.  相似文献   

15.
Two novel glycosides from the starfishSolaster dawsoni (Verrill) have been isolated and characterized: 24-O-(-D-xylopyranosyl)-5-cholestane-3,6,15,24,26-pentaol (solasteroside S1) and (24R)-29-O-[-D-galactofuranosyl-(16)--D-galactofuranosyl]-24-ethyl-5-cholestane-3, 6,8,15,16,29-hexaol (solasteroside S2).Translated fromIzvestiya Akademu Nauk. Seriya Khimicheskaya, No. 5, pp. 980–982, May, 1993.  相似文献   

16.
A preparative synthesis of glucosides of the lupane-type triterpene acids betulinic, dihydrobetulinic, betulonic, dihydrobetulonic, and 3,20-dioxo-30-norlupan-28-oic was proposed. Glycosylation of 3-hydroxyacids by -acetobromoglucose (ABG) with Ag2O was performed in pyridine (Py)to formglycosides at C-28, repeated glycosylation of which by these same reagents but in CH2Cl2 generated a glycoside bond at C-3 to form bisglucosides. 28-Glucosides of ketoacids were formed in high yields in both Py and CH2Cl2.  相似文献   

17.
New phosphorus-containing derivatives of grosshemin were synthesized in 68-70% yield by reacting this guaianolide with dialkylphosphites. Their structures were established by IR, PMR, 13C NMR, and 31P NMR spectroscopies and two-dimensional 1H-1H NMR spectroscopy (COSY). The reaction of grosshemin with dialkylphosphites was found to be highly stereoselective.  相似文献   

18.
The new triterpene glycoside cycloorbicoside C was isolated from the aerial parts of Astragalus orbiculatus Ledeb. (Leguminosae) and was identified as (23R,24S)-16,23;16,24-diepoxycycloartan-3,25-diol 3-O--D-xylopyranoside 25-O--D-glucopyranoside.  相似文献   

19.
Novel isoalantolactone dialkylphosphonates were synthesized in 70-87% yields by reacting this eudesmanolide with dialkylphosphites. Their structures were proved by spectral analysis using IR, PMR, 13C and 31P NMR, and two-dimensional 1H-1H (COSY) spectroscopy. The reaction of isoalantolactone with dialkylphosphites is highly stereoselective.  相似文献   

20.
The series of compounds of the general formulae HgX2(tzdtH) and HgX2(tzdtH)2 (X = Cl, Br, I; tzdtH = 1,3-thiazolidine-2-thione) have been prepared, as well as Hg(tzdt)2. IR, 1H, and 13C NMR spectral data of the complexes indicate thione donation, which is confirmed by the crystal structure analyses of [HgBr2(tzdtH)]2, [HgI2(tzdtH)]2, and HgI2(tzdtH)2. The structures of [HgBr2(tzdtH)]2 and [HgI2(tzdtH)]2 consist of centrosymmetric doubly bridged dimers, but they are not isostructural. The asymmetry in the HgX2Hg bridge is more pronounced in the bromo than in the iodo derivative [S–Hg–X(terminal) is 138.19(9)° for X = Br and 123.49(10)° for X = I], which is accompanied by the stronger Hg–S covalent bond in the bromo than in the iodo complex [2.435(4) vs. 2.510(3) Å]. The Hg–X(bridging) (X = Br, I) bond distances are shorter than the sum of van der Waals radii for mercury and X. Dimeric centrosymmetric complex units are held together only by van der Waals forces in [HgI2(tzdtH)]2, while in [HgBr2(tzdtH)]2 there is an intramolecular hydrogen bond of N–H Br type (3.34(1) Å). HgI2(tzdtH)2 exists as a mononuclear tetrahedral complex with two long Hg–S [2.672(1) Å] and two short Hg–I bond distances [2.688(1) Å] related by a twofold axis. The molecules of HgI2(tzdtH)2 are linked into infinite chains along the c axis by intermolecular N–H S [3.38(1) Å] hydrogen bonds.  相似文献   

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