Isolation and Structure Determination of Three New Sesquiterpenoids from Achillea millefolium

2012 ◽  
Vol 67 (5) ◽  
pp. 421-425 ◽  
Author(s):  
Umar Farooq ◽  
Afsar Khan ◽  
Saleha Suleman Khan ◽  
Shazia Iqbal ◽  
Rizwana Sarwar ◽  
...  
Keyword(s):  
Sesquiterpene Lactone ◽  
2D Nmr ◽  
Achillea Millefolium ◽  
Two Dimensional ◽  
H Nmr ◽  
Whole Plant ◽  
Phytochemical Investigation ◽  
Nmr Techniques ◽  
C Nmr

Phytochemical investigation of the whole plant of Achillea millefolium led to the isolation of three new sesquiterpenes which were trivially named as sesquiterpene lactone-esters A and B (1 and 2), and sesquiterpene lactone-diol (3). The structures of these compounds were determined with the help of one- and two-dimensional (1D and 2D) NMR techniques including 1H NMR, 13C NMR, HMQC, HMBC, COSY, and NOESY experiments.

scholarly journals Two New Sesquiterpene Lactone-esters from Achillea vermicularis

2008 ◽  
Vol 3 (11) ◽  
pp. 1934578X0800301
Author(s):  
Umar Farooq ◽  
Afsar Khan ◽  
Viqar Uddin Ahmad ◽  
Azhar-ul-Haq ◽  
Robina Farooq ◽  
...  
Keyword(s):  
Sesquiterpene Lactone ◽  
2D Nmr ◽  
Two Dimensional ◽  
H Nmr ◽  
Whole Plant ◽  
Phytochemical Investigation ◽  
Nmr Techniques ◽  
C Nmr

Phytochemical investigation of the whole plant of Achillea vermicularis led to the isolation of two new sesquiterpene lactone-esters, vermicularon A and B (1–2). The structures of these compounds were determined primarily with the help of one- and two-dimensional (1D and 2D) NMR techniques, including 1H NMR, 13C NMR, HMQC, and HMBC experiments.

E-Homolupane Derivatives Substituted in Position 17 and 22a. 1H NMR, 13C NMR and IR Spectra

1995 ◽  
Vol 60 (4) ◽  
pp. 619-635 ◽  
Author(s):  
Václav Křeček ◽  
Stanislav Hilgard ◽  
Miloš Buděšínský ◽  
Alois Vystrčil
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
Coupling Constants ◽  
Side Chain ◽  
Oxidation Reactions ◽  
H Nmr ◽  
Complete Assignment ◽  
Nmr Techniques ◽  
Intramolecular Association ◽  
C Nmr

A series of derivatives with various oxygen functionalities in positions 17,22a or 19,20 was prepared from diene I and olefin XVI by addition and oxidation reactions. The structure of the obtained compounds was confirmed by 1H NMR, 13C NMR and IR spectroscopy. The kind of intramolecular association of the 17α-hydroxy group was studied in connection with modification of the side chain and substitution in position 22a. Complete assignment of the hydrogen signals and most of the coupling constants was accomplished using a combination of 1D and 2D NMR techniques. The 1H and 13C NMR spectra are discussed.

scholarly journals A New Monodesmosidic Triterpenoid Saponin from the Leaves of Pometia Pinnata

2012 ◽  
Vol 7 (11) ◽  
pp. 1934578X1200701 ◽  
Author(s):  
Faryal Vali Mohammad ◽  
Mushtaq Noorwala ◽  
Viqar Uddin Ahmad ◽  
Aqib Zahoor ◽  
HJ. Nordin
Keyword(s):  
Structure Elucidation ◽  
Nmr Spectra ◽  
2D Nmr ◽  
Triterpenoid Saponin ◽  
Phytochemical Investigation ◽  
Nmr Techniques ◽  
C Nmr

Phytochemical investigation of the leaves of Pometia pinnata resulted in the isolation of a new triterpenoid saponin (1), together with a known compound, kaemferol 3- O-α-L-rhamnopyranoside (2). The structure of 1 was established as 3- O-[α-L-arabinofuranosyl-(1→4)–α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl]-hederagenin. The structure elucidation of the isolated compounds was based primarily on 1D- and 2D-NMR techniques, including 1H and 13C NMR spectra, DEPT, and by 2D COSY, HMQC, HMBC and TOCSY experiments.

Flavonoids from Achillea nobilis L.

2003 ◽  
Vol 58 (1-2) ◽  
pp. 11-16 ◽  
Author(s):  
Liselotte Krenn ◽  
Anca Miron ◽  
Enne Pemp ◽  
Ursula Petr ◽  
Brigitte Kopp
Keyword(s):  
Methyl Ether ◽  
Methanolic Extract ◽  
2D Nmr ◽  
Spectroscopic Methods ◽  
Esi Ms ◽  
H Nmr ◽  
Aerial Parts ◽  
Nmr Techniques ◽  
C Nmr

The detailed investigation of a methanolic extract of aerial parts of Achillea nobilis resulted in the isolation of 10 flavonoids. A new C-glycosylflavone, luteolin-6-C-apiofuranosyl-(1‴→2″)-glucoside, was isolated besides orientin, isoorientin, vitexin, isoschaftoside, luteolin- 7-O-β-glucuronide, luteolin-4′-O-β-glucoside and quercetin-3-O-methyl ether and two rare flavonolglycosides, quercetin-3-O-α-arabinosyl-(1‴→6″ )-glucoside and quercetin-3-O-methylether-7-O-β-glucoside. The structures were established either by comparison with authentic substances or by UV, 1H NMR and 13C NMR spectroscopic methods including 2ᴅ-NMR techniques and ESI-MS

Sesquiterpenes and Flavonoid Aglycones from a Hungarian Taxon of the Achillea millefolium Group

2002 ◽  
Vol 57 (11-12) ◽  
pp. 976-982 ◽  
Author(s):  
Sabine Glasl ◽  
Pavel Mucaji ◽  
Ingrid Werner ◽  
Armin Presser ◽  
Johann Jurenitsch
Keyword(s):  
2D Nmr ◽  
The Other ◽  
Achillea Millefolium ◽  
Spectroscopic Methods ◽  
Nmr Studies ◽  
Flavonoid Aglycones ◽  
H Nmr ◽  
Nmr Data ◽  
First Time ◽  
C Nmr

The investigation of a dichloromethane extract of flower heads of a Hungarian taxon of the Achillea millefolium group led to the isolation of three flavonoid aglycones, one triterpene, one germacranolide and five guaianolides. Their structures were elucidated by UV-VIS, EI- and CI-MS, 1H NMR and 13C NMR spectroscopic methods as well as by 2D-NMR studies and by selective 1D-NOE experiments. Besides apigenin, luteolin and centaureidin, β-sitosterol, 3β-hydroxy-11α,13-dihydro-costunolide, desacetylmatricarin, leucodin, achillin, 8α-angeloxy-leucodin and 8α-angeloxy-achillin were isolated. Both latter substances are reported here for the first time. Their NMR data were compared with those of the other guaianolides. The stereochemistry of 3β-hydroxy-11α,13-dihydro-costunolide was discussed and compared with data of the literature.

21,22-Disubstituted 18α,19βH-Ursane Derivatives with Oxabicyclooctane System in Ring E

1993 ◽  
Vol 58 (1) ◽  
pp. 173-190 ◽  
Author(s):  
Eva Klinotová ◽  
Jiří Klinot ◽  
Václav Křeček ◽  
Miloš Buděšínský ◽  
Bohumil Máca
Keyword(s):  
Spectral Data ◽  
Spin Systems ◽  
Coupling Constants ◽  
Complete Analysis ◽  
Nmr Spectrum ◽  
Proton Proton ◽  
H Nmr ◽  
Proton Coupling ◽  
C Nmr

Reaction of 3β-acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) and 20β,28-epoxy-21,22-dioxo-19α,19βH-ursan-3β-yl acetate (IIIb) with diazomethane afforded derivatives XII-XIV with spiroepoxide group in position 21 or 22, which were further converted into hydroxy derivatives XV and XVII. Ethylene ketals VIII-X were also prepared. In connection with the determination of position and configuration of the functional groups at C(21) and C(22), the 1H and 13C NMR spectral data of the prepared compounds are discussed. Complete analysis of two four-spin systems in the 1H NMR spectrum of bisethylenedioxy derivative Xb led to the proton-proton coupling constants from which the structure with two 1,4-dioxane rings condensed with ring E, and their conformation, was derived.

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 Labdane and Abietane Diterpenoids from Juniperus oblonga and Their Cytotoxic Activity

Molecules ◽  
2019 ◽  
Vol 24 (8) ◽  
pp. 1561 ◽  
Author(s):  
Qiao ◽  
Khutsishvili ◽  
Alizade ◽  
Atha ◽  
Borris
Keyword(s):  
Cell Lines ◽  
Human Tumor ◽  
2D Nmr ◽  
Human Tumor Cell Lines ◽  
Abietane Diterpenoids ◽  
Whole Plant ◽  
Phytochemical Investigation ◽  
Ic50 Values ◽  
First Time ◽  
Mcf 7

A phytochemical investigation of the whole plant of Juniperus oblonga led to the isolationof one previously undescribed labdane diterpenoid, (4R,5S,9S,10R)‐13‐des‐ethyl‐13‐oxolabda‐8(17),11E‐dien‐19‐oic acid (1), together with nine known diterpenoids (2–3, 6–12), two lignans (4, 5),and a coumarin (13). The structures of all the compounds were elucidated on the basis ofspectrometric data, primarily one‐dimensional (1D)‐ and two‐dimensional (2D)‐NMR and massspectrometry. Electronic circular dichroism (ECD) calculations determined the absoluteconfiguration of 1. In addition, the isolated compounds were evaluated for their cytotoxic activityagainst three human tumor cell lines (HepG2, MCF‐7, and HeLa). 6,12‐Dihydroxyabieta‐5,8,11,13‐tetraen‐7‐one (6) showed moderate cytotoxicity against all three cell lines with IC50 values rangingfrom 24.41 μM to 58.39 μM and trilobinone (10) showed weaker activity with IC50 values rangingfrom 56.93 μM to 79.98 μM. None of the isolated diterpenoids have been previously reported fromJuniperus oblonga, and five compounds are here reported from the genus Juniperus for the first time.

scholarly journals New Sensitive Kinetic Spectrophotometric Methods for Determination of Omeprazole in Dosage Forms

2009 ◽  
Vol 2009 ◽  
pp. 1-11 ◽  
Author(s):  
Ashraf M. Mahmoud
Keyword(s):  
Reference Method ◽  
Fixed Time ◽  
Dosage Forms ◽  
Charge Transfer Complexes ◽  
Specific Rate ◽  
Spectrophotometric Methods ◽  
H Nmr ◽  
Nmr Techniques ◽  
Kinetic Spectrophotometric

New rapid, sensitive, and accurate kinetic spectrophotometric methods were developed, for the first time, to determine omeprazole (OMZ) in its dosage forms. The methods were based on the formation of charge-transfer complexes with both iodine and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The variables that affected the reactions were carefully studied and optimized. The formed complexes and the site of interaction were examined by UV/VIS, IR, and1H-NMR techniques, and computational molecular modeling. Under optimum conditions, the stoichiometry of the reactions between OMZ and the acceptors was found to be 1 : 1. The order of the reactions and the specific rate constants were determined. The thermodynamics of the complexes were computed and the mechanism of the reactions was postulated. The initial rate and fixed time methods were utilized for the determination of OMZ concentrations. The linear ranges for the proposed methods were 0.10–3.00 and 0.50–25.00   with the lowest LOD of 0.03 and 0.14   for iodine and DDQ, respectively. Analytical performance of the methods was statistically validated; RSD was <1.25% for the precision and <1.95% for the accuracy. The proposed methods were successfully applied to the analysis of OMZ in its dosage forms; the recovery was 98.91–100.32%  0.94–1.84, and was found to be comparable with that of reference method.

Sign in / Sign up

Export Citation Format

Share Document