(8Z)-1(15),8(9)-Trinervitadien-3α-ol from Nasutitermes nigriceps termites. The revised structure for a deffense compound of Trinervitermes gratiosus termites

1990 ◽  
Vol 55 (6) ◽  
pp. 1580-1585 ◽  
Author(s):  
Irena Valterová ◽  
Miloš Buděšínský ◽  
Jan Vrkoč ◽  
Glenn D. Prestwich
Keyword(s):  
Detailed Analysis ◽  
Nmr Spectra ◽  
Suggested Structure

The structure of (8Z)-1(15),8(9)-trinervitadien-3α-ol (IIa) was established by a detailed analysis of its NMR spectra for a trinervitane derived alcohol isolated from the species Nasutitermes nigriceps. The previously suggested structure I for the same compound isolated from Trinervitermes gratiosus is now revised.

NMR Determination of the Structure of Peracetylated Icariside B2 from Veratrum Lobelianum BERNH.

1995 ◽  
Vol 60 (8) ◽  
pp. 1380-1385 ◽  
Author(s):  
Václav Suchý ◽  
Miloš Buděšínský ◽  
Karel Ubik ◽  
Daniel Grančai ◽  
Vlasta Földešiová
Keyword(s):  
Detailed Analysis ◽  
Nmr Spectra ◽  
Aerial Part ◽  
C Nmr

rel(1S,4S,5R)-3,3,5-Trimethyl-4-[( 1E)-3-oxo-1-butenyl]-4,5-epoxy-cyclohexyl-O-β-D-glucopyranoside (I) was isolated from the aerial part of Veratrum lobelianum BERNH. The structure was derived mainly from detailed analysis of 1H and 13C NMR spectra of its acetylated derivative II. Compound I has been already reported under the name icariside B2in Epimedium grandiflorum MORR. var. thunbergianum (MIQ.) NAKAI.

Triterpenoid Saponins from Clematis graveolens and Evaluation of their Insecticidal Activities

2015 ◽  
Vol 10 (9) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Rajeev Rattan ◽  
S. G. Eswara Reddy ◽  
Shudh Kirti Dolma ◽  
Bharat Inder Fozdar ◽  
Veena Gautam ◽  
...  
Keyword(s):  
Detailed Analysis ◽  
Spectroscopic Data ◽  
Nmr Spectra ◽  
2D Nmr ◽  
Aphis Craccivora ◽  
Triterpenoid Saponin ◽  
Triterpenoid Saponins ◽  
2D Nmr Spectra ◽  
Insecticidal Activities

A new hederagenin based triterpenoid saponin, clematograveolenoside A (1), along with three known saponins, tomentoside A (2), huzhangoside D (3) and clematoside S (4), were isolated from the roots and rhizomes of Clematis graveolens. The structure of new compound was elucidated on the basis of detailed analysis of chemical and spectroscopic data including 1D- and 2D NMR spectra. Compound 2 was found the most effective against aphid ( Aphis craccivora) with an LC50 of 1.2 and 0.5 mg/mL after treatment for 72 and 96 h, respectively and was followed by compound 4 (LC50 = 2.3 and 1.9 mg/mL) and 1 (LC50 = 3.2 and 2.6 mg/mL). In case of termite ( Coptotermis homii), compound 1 was found more toxic with an LC50 of 0.1 mg/L after 24 h of treatment followed by compound 2, 3 and 4 (LC50 = 0.1, 0.2 and 0.2 mg/mL, respectively).

Defensive substances from the frontal gland secretion of Nasutitermes nigriceps termite soldiers

1991 ◽  
Vol 56 (12) ◽  
pp. 2969-2977 ◽  
Author(s):  
Irena Valterová ◽  
Miloš Buděšínský ◽  
Jan Vrkoč
Keyword(s):  
Detailed Analysis ◽  
Infrared Spectra ◽  
Nmr Spectra ◽  
Gland Secretion ◽  
Volatile Fraction ◽  
Termite Species ◽  
Frontal Gland ◽  
Derivatives Of ◽  
Termite Soldiers ◽  
C Nmr

The components of the defence secretion of the soldiers of Nasutiterms nigriceps termite species (Isoptera: Termitidae: Nasutitermitinae) have been identified. In the volatile fraction the following components were found: α- and β-pinene, camphene, myrcene, α-terpinene, p-cymene, limonene and terpinolene. Ten diterpenic compounds (I - X), mostly derivatives of the tricyclic trinervitane, were found in the non-volatile fraction. The structure of the so far undescribed 1(15),8(19)-trinervitadiene-2β,3α,14α-triol triacetate (X) was determined on the basis of its mass and infrared spectra and a detailed analysis of 1H and 13C NMR spectra. Considerable differences were found in the composition of the non-volatile fraction of the secretion of the species of termites studied from various localities.

scholarly journals Achieving high resolution and optimizing sensitivity in spatial frequency encoding NMR spectroscopy: from theory to practice

2016 ◽  
Vol 18 (33) ◽  
pp. 22827-22839 ◽  
Author(s):  
Bertrand Plainchont ◽  
Daisy Pitoux ◽  
Ghanem Hamdoun ◽  
Jean-Michel Ouvrard ◽  
Denis Merlet ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
High Resolution ◽  
Spatial Frequency ◽  
Detailed Analysis ◽  
Nmr Spectra ◽  
Theory To Practice ◽  
Frequency Encoding

A detailed analysis of NMR spectra based on spatial frequency encoding is presented.

Synthesis and structure of iso-C4B18H22

1983 ◽  
Vol 48 (1) ◽  
pp. 228-231 ◽  
Author(s):  
Zbyněk Janoušek ◽  
Jaromír Plešek ◽  
Bohumil Štíbr ◽  
Stanislav Heřmánek
Keyword(s):  
Nmr Spectra ◽  
Suggested Structure ◽  
A Minor

Iso-C4B18H22 isolated earlier as a minor by-product in the H2CrO4 oxidation of the C2B9H12(-) anion was prepared in 10% yield by thermolysis of 7,8-C2B9H13. The originally suggested structure, 3-(8'-nido-5,6-C2B8H11)-1,2-C2B10H11, is confirmed by the 11B NMR spectra.

Structure of istanbulin A and istanbulin B - two sesquiterpenic lactones from Smyrnium olusatrum L.

1984 ◽  
Vol 49 (5) ◽  
pp. 1311-1317 ◽  
Author(s):  
Miloš Buděšínský ◽  
Miroslav Holub ◽  
David Šaman ◽  
Zdenka Smítalová ◽  
Ayhan Ulubelen ◽  
...  
Keyword(s):  
Circular Dichroism ◽  
Detailed Analysis ◽  
Spectral Methods ◽  
Nmr Spectra ◽  
H Nmr ◽  
Circular Dichroïsm

The structures of istanbulin A (I) and istanbulin B (III), including absolute configurations, have been derived on the basis of spectral methods, primarily a detailed analysis of 1H NMR spectra and circular dichroism measurements. Both substances belong to the type of (4R, 5S,10R)-eremophilan-8,12-olides.

Prosodic Impairment Associated With Traumatic Brain Injury

2009 ◽  
Vol 19 (3) ◽  
pp. 97-102
Author(s):  
Billy Irwin
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Detailed Analysis ◽  
Acoustic Characteristics ◽  
Individual Variations

Abstract Purpose: This article discusses impaired prosody production subsequent to traumatic brain injury (TBI). Prosody may affect naturalness and intelligibility of speech significantly, often for the long term, and TBI may result in a variety of impairments. Method: Intonation, rate, and stress production are discussed in terms of the perceptual, physiological, and acoustic characteristics associated with TBI. Results and Conclusions: All aspects of prosodic production are susceptible to the effects of damage resulting from TBI. There are commonly associated prosodic impairments; however, individual variations in specific aspects of prosody require detailed analysis.

NMR spectra and relaxation in incommensurate systems in the presence of a devil's staircase

1985 ◽  
Vol 46 (7) ◽  
pp. 1205-1209 ◽  
Author(s):  
R. Blinc ◽  
S. Žumer ◽  
D.C. Ailion ◽  
J. Nicponski
Keyword(s):  
Nmr Spectra ◽  
Devil's Staircase ◽  
Devil’S Staircase
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