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1.
N. D. Abdullaev O. E. Vasina V. A. Maslennikova N. K. Abubakirov 《Chemistry of Natural Compounds》1986,21(5):616-622
The PMR and13C NMR spectra of new withasteroids — visconolide and 28-hydroxywithaperuvin C, isolated fromPhysalis viscosa L. — have been investigated. A detailed analysis of the spectral characteristics obtained is given. For visconolide is proposed the structure of 4,12,17,28-pentahydroxy-1-oxo-5, 6-epoxy-22R-witha-2,24-dienolide, and for 28-hydroxywithaperuvin C that of 6,14,17,20R, 28-pentahydroxy-l-oxo-22R-witha-2, 4, 24-trienolide.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 657–663, September–October, 1985. 相似文献
2.
O. E. Vasina V. A. Maslennikova N. D. Abdullaev N. K. Abubakirov 《Chemistry of Natural Compounds》1986,22(5):560-565
Two new withasteroid have been isolated fromPhysalis angulata L. — 14α-hydroxyixocarpanolide and 24,25-epoxywithanolide D. 14α-hydroxyixocarpanolide — C28H40O7, mp 245–250°C (from methanol), [α] D 20 +29±2° (chloroform). 24,25-Epoxywithanolide D — C28H38O7, mp 257–261°C (from methanol, [α] D 20 +23±2° (chloroform). On the basis of its UV, IR, CD, mass, and1H and13C NMR spectra the structure of 5α,14α,20R-trihydroxy-1-oxo-6α,7α-epoxy-22R-2itha-2-enolide is suggested for 14α-hydroxyixocarpanolide. On the basis of spectral characteristics and the preparation of 4β-acetoxy and 4-oxo derivatives of 24,25-epoxywithanolide D, the structure of 4β,20R-dihydroxy-1-oxo-5β,6β;24S,25S-diepoxy-22R-witha-2-enolide is proposed for it. 相似文献
3.
Nine new steroidal lactones of the withanolide series (withanolides E-M) have been isolated from the leaves of Withania somnifera Dun (Solanaceae) growing in the southern coastal plane of Israel. This population of W. somnifera constitutes a new chemotype and is designated as chemotype III. The following structures have been assigned to seven of the above compounds:Withanolide G, 20α-hydroxy-1-oxo-20R,22R-witha-2,5,8(14),24-tetraenolide (1); withanolide H, 20α,27-dihydroxy-1-oxo-20R,22R-witha-2,5,8(14),24-tetraenolide (2); withanolide I, 20α-hydroxy-1-oxo-20R,22R-witha-3,5,8(14),24-tetraenolide (3); withanolide J, 17α,20α-dihydroxy-1-oxo-20S,22R-witha-2,5,8(14),24-tetraenolide (4); withanolide K, 17α,20α-dihydroxy-1-oxo-20S,22R-witha-3,5,8(14),24-tetraenolide (5); withanolide L, 17α,20α-dihydroxy-1-oxo-20S,22R-witha-2,5,14,24-tetraenolide (6); withanolide M, 17α,20α-dihydroxy-1-oxo-14α,15α-epoxy-20S,22R-witha-2,5,24-trienolide (7). 相似文献
4.
G. V. Pirtskhalava M. B. Gorovits T. T. Gorovits N. K. Abubakirov 《Chemistry of Natural Compounds》1979,15(4):446-452
From a methanolic extract of the bulbs ofAllium turcomanicum Rgl. we have isolated a new furostanol glycoside, turoside C (I). An acid hydrolysate was found to contain the aglycone — neoagigenin (II) — and the sugars D-xylose, D-glucose, and D-galactose in a ratio of 1:4:1. The structure of the furostanol (I) has been established by methylation, enzymatic hydrolysis, and oxidative cleavage, and also by the oxidative cleavage of (II), as (25S)-5α-furostan-2α,3β,6β,22α,26-pentaol 26-O-β-D-glucopyranoside 3-O-{[O-β-D-xylopyranosyl-(1→3)]-[O-β-D-glucopyranosyl-(1→2)-O-β-D-glucopyranosyl-(1→2)]-O-β-D-glucopyranosyl-(1→4)-β-D-galacto-pyranoside}. 相似文献
5.
T. V. Ganenko M. I. Isaev T. T. Gorovits A. S. Gromova V. I. Lutskii A. A. Semenov N. K. Abubakirov 《Chemistry of Natural Compounds》1984,20(4):433-438
A new glycoside — foetoside C — has been isolated from the epigeal part ofThalictrum foetidum L. and, on the basis of chemical transformations and spectral characteristics its structure has been established as oleanolic acid 28-[O-α-D-glycopyranosyl-(1 → 6)-O-β-D-glucopyranoside] 3-O-[O-β-D-xylopyranosyl-(1 → 3)-O-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranoside]. 相似文献
6.
The structures of two new cycloartane glycosides — cyclocarposides A and C, isolated from the herbAstragalus coluteocarpus Boiss. — have been established on the basis of spectral characteristics and chemical transformations. Cyclocarposides A and C are: 204R,24S-epoxycycloartane-3β,6α,17β,25-tetraol 3-O-(2-O-acetyl-β-D-xylopyranoside)6-O-(2-O-acetyl-α-L-rhamnopyranoside) and 20R,24S-epoxycyloartane-3β,6α,16β,25-tetraol 3-O-(2-O-acetyl-β-D-xylopyranoside) 6-O-α-L-rhamnopyranoside, respectively. 相似文献
7.
The 13C NMR spectra of 29 highly oxygenated C, steroids with the withanolide skeleton, 24 of which are naturally occurring substances or acetates thereof, were recorded and the carbon signals fully assigned. The shifts of the heavily functionalized A/B ring system can serve as a ‘fingerprint’ for the different substitution patterns. A study of the effects of hydroxyl substitution in the ring D/side chain part of the molecules leads to conformational information, including preferred rotamers around the 17—20 and 20—22 bonds. Systems with both 17α- and 17β-oriented side chains are thus analysed. 相似文献
8.
G. K. Oleinikova T. A. Kuznetsova N. S. Ivanova A. I. Kalinovskii N. V. Rovnykh G. B. Elyakov 《Chemistry of Natural Compounds》1982,18(4):430-434
A glycoside, holothurin A1 has been isolated from the polar glyosidic fractions of the holothuriansH. floridana andH. grisea. The complete structure of the glycoside has been established; it is: 3β-[0-(3-0-methyl-β-D-glucopyranosyl)-(1 → 3)-0-β-D-glucopyranosyl-(1 → 4)-0-β-D-quinovopyranosyl-(1 → 2)-(4-sulfato-β-D-xylopyranosyl)oxy]holosta-9(11)-ene-12α,17α,22ξ-triol. Details of the IR and1H and13C NMR spectra of the compounds obtained are given. 相似文献
9.
Triterpene glycosides ofAstragalus and their genins. VI. Cycloasgenin C fromAstragalus taschkendicus
M. I. Isaev M. B. Gorovits N. D. Abdullaev N. K. Abubakirov 《Chemistry of Natural Compounds》1982,18(4):424-430
A new isoprenoid — cycloasgenin C — has been isolated from the roots of the plantAstragalus taschkendicus C. Bge, and on the basis of chemical transformations and spectral characteristics its structure has been established as 24(R)-cycloartane-3β,6α,16β,24,25-pentaol. 相似文献
10.
V. Kabaleeswaran R. Malathi S. S. Rajan G. Suresh N. S. Narashiman 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):82-84
The crystal structures of two intact limonoids, nimonol,7α‐acetyl‐17α‐(3‐furyl)‐6α‐hydroxy‐4α,4β,8β‐trimethyl‐5α,18α‐androsta‐1,14‐dien‐3‐one (C28H36O5), and 6‐oxonimonol,7α‐acetyl‐17α‐(3‐furyl)‐4α,4β,8β‐trimethyl‐5α,18α‐androsta‐1,14‐diene‐3,6‐dione (C28H34O5), are reported. The molecular features are mostly the same in the two structures; however the orientations of the acetoxy group are different in the two structures. The packing in nimonol is due to O—H?O hydrogen bonds while in 6‐oxonimonol it is due to C—H?O hydrogen bonds. 相似文献
11.
V. T. Bauman E. E. Shul’ts M. M. Shakirov G. A. Tolstikov 《Russian Journal of Organic Chemistry》2007,43(4):526-537
Bromination of endo-ethenotetrahydrothebaine derivatives having a pyrrolidine ring fused at the C7-C8 bond, namely 1′-substituted 4,5α-epoxy-6α,14-etheno-3,6-dimethoxy-17-methyl-2′,5′,7β,8β-tetrahydro-1′H-14α-pyrrolo[3′,4′:7,8]morphinan-2′,5′-diones, 1′-aryl-4,5α-epoxy-6α,14-etheno-3,6-dimethoxy-17-methyl-2′,5′,7β,8β-tetrahydro-1′H-14α-pyrrolo[3′,4′:7,8]morphinans, and 4,5α-epoxy-6α,14-etheno-2′α-hydroxy-3,6-dimethoxy-17-methyl-1′-phenyl-2′,5′,7β,8β-tetrahydro-1′H-14α-pyrrolo[3′,4′:7,8]morpphinan-5′-one, with molecular bromine in formic acid smoothly afforded the corresponding 1-bromo derivatives. Iodination of 4,5α-epoxy-6α,14-etheno-3,6-dimethoxy-17-methyl-1′-phenyl-2′,5′,7β,8β-tetrahydro-1′H-14α-pyrrolo[3′,4′:7,8]-4,5α-epoxy-6α,14-etheno-3,6-dimethoxy-17-methyl-1′-phenyl-2′,5′,7β,8β-tetrahydro-1′H-14α-pyrrolo[3′,4′:7,8]-morphinan-2′,5′-dione with iodine(I) chloride gave 4,5α-epoxy-6α,14-etheno-1-iodo-3,6-dimethoxy-17-methyl-1′-phenyl-2′,5′,7β,8β-tetrahydro-1′H-14α-pyrrolo[3′,4′:7,8]morphinan-2′,5′-dione. The resulting 1-halo derivatives were brought into the Heck reaction with acrylic acid esters to obtain 1-[(E)-2-(alkoxycarbonyl)ethenyl]-substituted compounds. Demethylation of the 6-methoxy group in 1-bromo-endo-ethenotetrahydrothebaines was accomplished using boron(III) bromide in chloroform. 相似文献
12.
V. I. Lutskii E. A. Khamidullina A. S. Gromova A. A. Semenov 《Chemistry of Natural Compounds》1989,25(4):436-441
Two genins — squarrogenin 1 and squarrogenin 2 — have been isolated from nodding meadow rue by the hydrolysis of squarrosides A1 and A2. The compounds are epimeric at C-21 and have the following structures: 1 — (21R, 22S, 23R)-21-methoxy-21,23-epoxycycloart-24-ene-3β,22β-30-triol, C31H50O5, mp 169–171°C (hexane-acetone), [α] 546 20 ?11.06° (c 4.52; pyridine); and 2 — (21S, 22S, 23R)-21-methoxy-21,23-epoxycycloart-24-ene-3β,22β,30-triol, C31H50O5, mp 190–193°C (hexane-acetone), [α] 546 20 +106.6° (c 0.3; pyridine). The results of1H and13C NMR spectroscopy and of mass spectrometry for the new compounds are given. 相似文献
13.
Rita C. Almeida‐Lafet Marcelo J. P. Ferreira Vicente P. Emerenciano Maria A. C. Kaplan 《Helvetica chimica acta》2010,93(12):2478-2487
In the first phytochemical study of the Aureliana genus (Solanaceae), two new withanolides, 1 and 2 , together with two known sterols, were isolated from the MeOH extract of the leaves of Aureliana fasciculata var. fasciculata. The structures were established as (4S,22R)‐16α‐acetoxy‐5β,6β‐epoxy‐4β,17α‐dihydroxy‐1‐oxowitha‐2,24‐dienolide (aurelianolide A) and (4S,22R)‐16α‐acetoxy‐4β,17α‐dihydroxy‐1‐oxowitha‐2,5,24‐trienolide (aurelianolide B). The new compounds possessed the unusual 16α,17α‐dioxygenated group and were fully characterized by spectroscopic techniques, including 1H‐ and 13C‐NMR (DEPT), as well as 2D‐NMR (HMBC, HMQC, 1H,1H‐COSY, NOESY) experiments, and HR‐MS. 相似文献
14.
Withasteroids ofPhysalis. IV. 28-Hydrowithaphysanolide.13C NMR spectrum of 14-α-hydroxywithasteroids
N. D. Abdullaev E. A. Maslennikova R. N. Tursunova N. K. Abubakirov M. R. Yagudaev 《Chemistry of Natural Compounds》1984,20(2):182-191
A new withasteroid has been isolated fromPhysalis viscosa L. — 28-hydroxywithaphysanolide, with mp 234°C, composition C28H38O8. The13C NMR spectra of a number of withasteroids have been investigated. For 28-hydroxywithaphysanolide we propose the structure 4,14,17,20R,28-pentahydroxy-l-oxo-22R-witha-2,5,24-trienolide. The corresponding corrections have been made in the structural formulas of withaphysanolide and physalactone.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 197–207, March–April, 1984. 相似文献
15.
Arun A. YadavPrajakta S. Sarang Manishankar SauSrinath Thirumalairajan Girish K. Trivedi Manikrao M. Salunkhe 《Tetrahedron letters》2012,53(28):3599-3602
[5+2] Cycloaddition followed by asymmetric dihydroxylation procedure have been utilized to prepare novel cyclitols. Accordingly, rac-2α-hydroxy-6α-ethoxy-1,5-anhydro cyclohept-3-ene, 10 derived from [5+2] cycloaddition of 3-oxidopyrylium ylide and vinyl ether has been recognized as a seven-membered carbasugar equivalent and elaborated to 1,4,5-tribenzoyloxy-2-ethoxy cycloheptanes through a flexible, regio- and stereoselective strategy involving Sharpless asymmetric dihydroxylation conditions to resolve the compounds obtained. The structures and relative configurations of newly synthesized (+)-2α-acetoxy-6α-ethoxy-3β,4β-dihydroxy-1,5-anhydro cycloheptane ((+)-12)); (−)-1β,4β,5β-tribenzoyloxy-6α-ethoxy cycloheptane ((−)-17) and (+)-1α,4α,5α-tribenzoyloxy-6β-ethoxy cycloheptane ((+)-17) are unambiguously established by single crystal X-ray analysis and duly supported by 1H and 13C NMR spectroscopy data. 相似文献
16.
L. K. Shubina T. V. Moskovkina V. A. Stonik G. B. Elyakov 《Chemistry of Natural Compounds》1981,17(5):418-422
The total sterols have been isolated fromHalocynthia aurantium by column chromatography on silica gel. The following steroid alcohols have been identified in it with the aid of GLC, GLC-MS, and1H NMR: 5α-cholestan-3β-ol, 24ξ-methylcholestan-3β-ol, 24ξ-ethylcholestan-3β-ol, 4ξ-methyl-24ξ-ethyl-5α-cholestan-3β-ol, cholest-5-en-3β-ol, 24ξ-methylcholest-5-en-3β-ol, 24ξ-ethylcholes-5-en-3β-ol, 5α-cholest-22-en-3β-ol, 24-nor-5α-cholest-22-en-3β-ol, cholesta-5,22-dien-3β-ol, 24ξ-methylcholesta-5,22-dien-3β-ol, 24-norcholesta-5,22-dien-3β-ol, 24-ethylcholesta-5,24(28)-dien-3β-ol, and 24-methylcholesta-5,24(28)-dien-3β-ol. 相似文献
17.
Shou‐Li Wang Zhong Chen Xiao‐Jing Tong Yan‐Li Liu Xia Li Qiong‐Ming Xu Xiao‐Ran Li Shi‐Lin Yang 《Helvetica chimica acta》2013,96(6):1126-1133
Three new triterpenoids, 21β,22α‐diangeloyloxy‐3β,15α,16α,28‐tetrahydroxyolean‐12‐en‐23‐al ( 1 ), 21β‐angeloyloxy‐3β,15α,16α,28‐tetrahydroxy‐22α‐(2‐methylbutanoyloxy)olean‐12‐en‐23‐al ( 2 ), and 21β‐angeloyloxy‐3β,16α,28‐trihydroxy‐22α‐(2‐methylbutanoyloxy)olean‐12‐en‐23‐al ( 3 ), along with six known triterpenoids, were isolated from the roots of Camellia oleifera C.Abel . The structures of compounds 1 – 3 were elucidated on the basis of spectroscopic analyses. Moreover, all compounds isolated were evaluated for their cytotoxic activities by MTT (=3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide) assay. 相似文献
18.
A. V. Kamernitskii V. G. Levi I. G. Reshetova V. S. Bogdanov V. A. Pavlov E. G. Cherepanova 《Chemistry of Natural Compounds》1982,18(1):59-66
The paper is devoted to the synthesis of 3,17α,20-trihydroxy-16β,23-epoxy-21,24-dinor-5αH-cholan-6-one and 3,5α,17α,20-tetrahydroxy-16β,23-epoxy-21,24-dinorcholan-6-one and derivatives of them. It has been shown that the reduction of 3,17α-dihydroxy-16β,23-epoxy-21,24-dinorchol-5-en-20-one with sodium tetrahydroborate and with diborane takes place stereospecifically with different spatial directivities: in the products of diborane reduction, ring E exists in the boat form, as has been shown by1H and13C NMR methods. The trans linkage of rings A/B in the modified steroids has been confirmed by their circular dichroism spectra. 相似文献
19.
Bingyou Yang Qiuhong Wang Yonggang Xia Weisheng Feng Haixue Kuang 《Helvetica chimica acta》2007,90(8):1522-1528
Three new withanolide compounds named baimantuoluoline A ( 1 ), B ( 2 ), and C ( 3 ) and the two known withanolides withafastuosin E ( 4 ) and withametelin C ( 5 ) were isolated from the fraction exhibiting activity for psoriasis in the flower of Datura metel L. The three new structures were determined as (5α,6α,7α,12β,15β,22R)‐6,7‐epoxy‐5,12,15‐trihydroxy‐1‐oxowitha‐2,24‐dienolide ( 1 ), (5α,6β,15β,22R)‐ 5,6,15,21‐tetrahydroxy‐1‐oxowith‐24‐enolide ( 2 ), and (5α,6β,12β,22R)‐5,6,12,21‐tetrahydroxy‐27‐methoxy‐1‐oxowitha‐2,24‐dienolide ( 3 ) on the basis of extensive spectroscopic data (HR‐ESI‐MS, 1H‐ and 13C‐NMR, 1H,1H‐COSY, HSQC, HMBC, and NOESY) (withanolide=22‐hydroxyergostan‐26‐oic acid δ‐lactone). 相似文献
20.
Glycosides of marine invertebrates. Structure of holothurin A2 from the holothurianHolothuria edulis
The structure of a new glycoside fromHolothuria edulis, holothurin A2, has been established with the aid of periodate oxidation, methylation, Smith degradation, and13C NMR spectroscopy. The structure of the glycoside has been determined as holost-9(11)-ene-3β,12α,17α-triol 3-0-{2-0-[3-0-methyl-β-D-glucopyranosyl-(1→3)-0-β-D-glucopyranosyl-(1→4)-0-β-D-quinovopyranosyl]-4-0-sulfate-β-D-xylopyranoside}. 相似文献