scholarly journals Two New Diterpene Phenols from Calocedrus decurrans

2010 ◽  
Vol 5 (4) ◽  
pp. 1934578X1000500
Author(s):  
Sheeba Veluthoor ◽  
Shujun Li ◽  
Rick G. Kelsey ◽  
Marc C. Dolan ◽  
Nicholas A. Panella ◽  
...  
Keyword(s):  
Natural Product ◽  
2D Nmr ◽  
Nmr Techniques ◽  
First Time ◽  
New System

Two new p-cymene based diphenols (1-2) were isolated from the heartwood of Calocedrus decurrans. Structures were elucidated by 1D and 2D NMR techniques and HRMS. Libocedroquinone (3) was also isolated as a natural product for the first time. A new system of nomenclature is proposed for description of such oligomeric p-cymene derivatives.

Flavon- and Flavonolglycosides from Achillea pannonica Scheele

2001 ◽  
Vol 56 (7-8) ◽  
pp. 521-525 ◽  
Author(s):  
Denata Kasaj ◽  
Liselotte Krenn ◽  
Sonja Prinz ◽  
Antje Hüfner ◽  
Shi Shan Yuc ◽  
...  
Keyword(s):  
Methanolic Extract ◽  
2D Nmr ◽  
Flavonoid Glycosides ◽  
Spectroscopic Methods ◽  
Esi Ms ◽  
Aerial Parts ◽  
Nmr Techniques ◽  
Chemotaxonomic Study ◽  
First Time ◽  
C Nmr

The detailed investigation of a methanolic extract of aerial parts of Achillea pannonica SCHEELE. within a chemotaxonomic study led to the isolation of 6 flavonoid glycosides. Besides rutin, apigenin-7-O-glucopyranoside, luteolin-7-O-glucopyranoside, apigenin-7-O-rutinoside and acacetin-7-O-rutinoside, an unusual flavondiglucoside was isolated. Its structure was established by UV, 1HNMR and 13C NMR spectroscopic methods including 2D-NMR techniques and ESI-MS as luteolin-7,4′-O-β-diglucoside. This substance is reported for the first time in the genus Achillea. Chemotaxonomic aspects are discussed briefly

scholarly journals Flavonoids from Milletia leucantha and Their Cytotoxicity

2018 ◽  
Vol 13 (8) ◽  
pp. 1934578X1801300
Author(s):  
Uraiwan Sriphana ◽  
Chavi Yenjai ◽  
Siriporn Tungnoi ◽  
Jongjai Srirapa ◽  
Auemporn Junsongduang
Keyword(s):  
Cytotoxic Activity ◽  
Vero Cell ◽  
Cell Line ◽  
Vero Cells ◽  
2D Nmr ◽  
Nmr Techniques ◽  
Vero Cell Lines ◽  
First Time ◽  
Flavonol Derivatives ◽  
Mcf 7

Two known chalcones (1–2), five known flavonol derivatives (3 and 5–8) and one flavone (4) were isolated for the first time from fruits of Millettia leucantha Kurz. In addition, 5 was found for the first time from this genus. Their structures were elucidated on the basis of IR, MS, 1D and 2D NMR techniques. Chalcone 1 exhibited moderate cytotoxicity against the MCF-7 cell line with an IC50 value of 50.93 μM, whereas this compound showed inactive cytotoxicity against Vero cells. Compound 2 exhibited cytotoxicity against the KB, NCI-H187 and Vero cell lines with IC50 values of 63.64, 114.44 and 28.44 μM, respectively. Compound 8 only showed cytotoxic activity against the KB cell line with an IC50 value of 110.23 μM.

scholarly journals A HOPANE TRITERPENOID FROM THE MYCELIUM OF Isaria japonica IN VIETNAM

2017 ◽  
Vol 55 (5) ◽  
pp. 535
Author(s):  
Nguyen Ngoc Tuan ◽  
Tran Thi Kim Anh ◽  
Ping-Chung Kuo ◽  
Tran Dinh Thang
Keyword(s):  
Spectral Data ◽  
13C Nmr ◽  
Methanol Extract ◽  
2D Nmr ◽  
1H And 13C Nmr ◽  
Nmr Techniques ◽  
First Time

A hopane triterpenoid (11b, 22-dihydroxyhopane) was isolated from the methanol extract of the mycelium of Isaria japonica in Vietnam. The structure of this compound was elucidated using a combination of 1D and 2D NMR techniques (1H-, 13C-NMR, COSY, HSQC and HMBC). In the study, we reported the comprehensive 1H- and 13C-NMR spectral data of 11b, 22-dihydroxyhopane for the first time.

scholarly journals Antialactone: A New γ-Lactone from Antiaris Africana, and its Absolute Configuration Determined from TDDFT CD Calculations

2008 ◽  
Vol 3 (2) ◽  
pp. 1934578X0800300 ◽  
Author(s):  
Vouffo Bertin ◽  
Hidayat Hussain ◽  
Simeon F. Kouam ◽  
Etienne Dongo ◽  
Gennaro Pescitelli ◽  
...  
Keyword(s):  
Natural Product ◽  
Absolute Configuration ◽  
Betulinic Acid ◽  
Spectroscopic Data ◽  
Nmr Spectra ◽  
2D Nmr ◽  
Stem Bark ◽  
Cd Spectra ◽  
2D Nmr Spectra ◽  
First Time

Four compounds were isolated from the stem bark of Antiaris africana. One of them, a γ-lactone named antialactone (1a), is reported for the first time as a natural product. The structures were determined by comprehensive analyses of their 1D and 2D NMR spectra and EI MS data. The absolute configuration of antialactone acetate (1b) was established by TDDFT CD calculations and comparison with measured CD spectra. The remaining three known compounds were identified, by comparing their spectroscopic data with those reported in the literature, as lichenxanthone, β-sitosterol, and betulinic acid.

Biotransformation of caffeic acid by Momordica charantia peroxidase

2008 ◽  
Vol 86 (8) ◽  
pp. 821-830 ◽  
Author(s):  
Xiang Wan ◽  
Haili Liu ◽  
Xuefeng Huang ◽  
Jianguang Luo ◽  
Lingyi Kong
Keyword(s):  
Antioxidant Activity ◽  
Caffeic Acid ◽  
2D Nmr ◽  
Momordica Charantia ◽  
The Other ◽  
Oxidative Activity ◽  
Nmr Techniques ◽  
New Compounds ◽  
First Time

Biotransformation of caffeic acid with H2O2/Momordica charantia peroxidase at pH 5.0, 25 °C in the presence of acetone has resulted in the isolation of three caffeic acid trimers 1–3, five caffeic acid dimers 4–8, and one monomer 9. Among them, seven (1–7) are new compounds, and two (8 and 9) are known compounds, including one compound (9), which was obtained by biotransformation for the first time. The structures were established by 2D NMR techniques, such as HSQC, HMBC, and NOESY measurements. The possible mechanism for the formation of the products is also discussed. This is the first time that caffeic acid trimers have been obtained through the biotransformation of catalyzed by peroxidase in vitro. Compound 5 has shown much stronger anti-oxidative activity than the other caffeic acid polymers obtained.Key words: Momordica charantia peroxidase, caffeic acid, polymers of caffeic acid, biotransformation, antioxidant activity.

The Structure Elucidation and Antimicrobial Activities of Nonsterol Triterpenoids from Ixeris chinensis

2014 ◽  
Vol 69 (9-10) ◽  
pp. 1021-1025 ◽  
Author(s):  
Qing-Hu Wang ◽  
Na-Ren-Chao-Ke-Tu Han ◽  
Na-Yin-Tai Dai ◽  
Xiao-Lan Wu ◽  
Wen-Quan Tai ◽  
...  
Keyword(s):  
Petroleum Ether ◽  
Structure Elucidation ◽  
Petroleum Ether Extract ◽  
2D Nmr ◽  
Antimicrobial Activities ◽  
Spectroscopic Methods ◽  
Ether Extract ◽  
Esi Ms ◽  
Nmr Techniques ◽  
First Time

Abstract An investigation of the petroleum ether extract from Ixeris chinensis Nakai has led to the isolation of a new compound, 3-O-acetyl-22,28-cyclobauer-7-en-3β-ol (1), together with four known compounds which have been isolated from this plant for the first time, namely taraxast-20-en-3β-ol (2), 3-O-acetyl-taraxast-20-en-3β-ol (3), taraxast-20(30)-en-3β-ol (4), and 3-O-acetyl-taraxast-20(30)- en-3β-ol (5). The structures of the isolated compounds have been elucidated on the basis of spectroscopic methods including UV, IR, ESI-MS, 1D NMR, 2D NMR techniques, and by comparison with data reported in the literature. All compounds have been evaluated for their activity against various bacteria and shown to give good results

scholarly journals Azocalix[4]arene-Rhodamine Supramolecular Hypoxia-Sensitive Systems: A Search for the Best Calixarene Hosts and Rhodamine Guests

Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5451
Author(s):  
Diana Mironova ◽  
Vladimir Burilov ◽  
Farida Galieva ◽  
Mohamed Ali Mohamed Khalifa ◽  
Sofia Kleshnina ◽  
...  
Keyword(s):  
Electrostatic Interactions ◽  
2D Nmr ◽  
Sodium Dithionite ◽  
Aryl Ether ◽  
Host Guest Complex ◽  
Leuco Form ◽  
Nmr Techniques ◽  
Upper Rim ◽  
First Time ◽  
Rhodamine Dyes

A potential hypoxia-sensitive system host-guest complex of three calixarenes (including two with four anionic carboxyl and sulphonate azo fragments on the upper rim and a newly synthesized bis-azo adduct of calixarene in the cone configuration with azo fragments on the lower rim with the most widespread cationic and zwitterionic rhodamine dyes (123, 6G and B)) was studied using UV-VIS spectrometry and fluorescence as well as 1D and 2D NMR techniques. It was found that all three calixarenes form a complex with rhodamine dyes with a 1:1 composition. The association constants of calixarene-dye complexes with sulfonate calixarenes, especially in the case of tetra-anionic calixarene, turned out to be higher compared with carboxyl calixarene due to the more intense electrostatic interactions. For the first time using an HRESI MS technique, it was shown that the treatment of rhodamine 6G and 123 with sodium dithionite (SDT) produces a non-fluorescent leuco form of the dye, and only rhodamine B can be used with SDT without the occurrence of a side reduction. Moreover, it was identified that in addition to the reduction in the azo groups, SDT causes partial cleavage of the aryl ether bonds. The found features of SDT should be taken into account when SDT is used as an azoreductase mimic.

Isolation, Structure Elucidation and Activity of Anthracycline Acetates from a Terrestrial Streptomyces sp.

2003 ◽  
Vol 58 (12) ◽  
pp. 1242-1246 ◽  
Author(s):  
Serge Fotso ◽  
Rajendra P. Maskey ◽  
Iris Grün-Wollny ◽  
Hartmut Laatsch
Keyword(s):  
Molecular Weight ◽  
Natural Product ◽  
Structure Elucidation ◽  
Ethyl Acetate Extract ◽  
2D Nmr ◽  
Streptomyces Sp ◽  
Naturally Occurring ◽  
Nmr Data ◽  
New Antibiotics ◽  
First Time

The red coloured ethyl acetate extract of the Streptomyces sp. isolate GW37/3236 delivered the two new antibiotics 13-O-acetyl-bisanhydro-13-dihydrodaunomycinone (3c) and 4,13-O-diacetylbisanhydro- 4-O-demethyl-13-dihydrodaunomycinone (3d) and additionally several known compounds. The quinones 3c and 3d are the first naturally occurring quinone acetates. Their structures were derived by comparison of the NMR data with those of bisanhydro-13-dihydrodaunomycinone (3b) and by interpretation of the 2D NMR data accompanied by the molecular weight and formula. 2-Acetamido-3-hydroxybenzamide (5) was also isolated from the extract and was identified by comparison of the NMR data with those of 2-acetamidobenzamide and by 2D NMR correlations. 6,9,11- Trihydroxy-4-methoxy-5,12-naphthacenedione (4) is isolated for the first time as a natural product.

scholarly journals Synthesis and structure revision of symplocin A

2017 ◽  
Vol 4 (6) ◽  
pp. 995-1004 ◽  
Author(s):  
Lu-Ping Shao ◽  
Chang-Mei Si ◽  
Zhuo-Ya Mao ◽  
Wen Zhou ◽  
Tadeusz F. Molinski ◽  
...  
Keyword(s):  
Natural Product ◽  
2D Nmr ◽  
One Pot ◽  
Linear Peptide ◽  
Structure Revision ◽  
First Time

Symplocin A, a linear peptide has been synthesized for the first time employing our previously established ‘one-pot intramolecular tandem protocol’. Moreover, the stereochemistry of natural symplocin A was unambiguously revised through the confirmation by 1D NMR, 2D NMR, and HPLC comparisons with an authentic natural product.

scholarly journals Pentacyclic Triterpenoids from Maytenus cuzcoina

2017 ◽  
Vol 12 (5) ◽  
pp. 1934578X1701200
Author(s):  
Carolina P. Reyes ◽  
Ignacio A. Jiménez ◽  
Isabel L. Bazzocchi
Keyword(s):  
2D Nmr ◽  
Bark Extract ◽  
Phytochemical Analysis ◽  
Spectroscopic Methods ◽  
Root Bark ◽  
Pentacyclic Triterpenoids ◽  
Isolation And Characterization ◽  
Nmr Techniques ◽  
First Time

Phytochemical analysis of the root bark extract of Maytenus cuzcoina (Celastraceae) led to the isolation and characterization of sixteen triterpenoids with a 6/6/6/6/6 pentacyclic system, including the new 22α-hydroxy-29-methoxy-3β-tetradecanoate-olean-12-ene, and 3β,24β-epoxy-29-methoxy-2α,3α,6α-trihydroxy- D:A-friedelane that is reported for the first time as a natural product. This is the first instance of the isolation of a tetradecanoate triterpene ester from a Celastraceae species. The structures were elucidated on the basis of spectrometric and spectroscopic methods, including 1D and 2D NMR techniques.

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