scholarly journals Isolation and Characterization of New Ceramides from Aerial Parts of Lepidaploa cotoneaster

2012 ◽  
Vol 7 (6) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Edlene O. dos Santos ◽  
Marilena Meira ◽  
Ademir E. do Vale ◽  
Jorge M. David ◽  
Luciano P. de Queiróz ◽  
...  

Two new ceramides were isolated from the bulbs of Lepidaploa cotoneaster (Willd. ex Spreng.) H. Rob. [ Vernonia cotoneaster (Willd. ex Spreng.) Less.)], in addition to germanicol, β-sitosterol, stigmasterol, 3-β- O-β-D-glucopyranosyl-sitosterol, lupeol, lupeoyl acetate and tiliroside. The structures of the new compounds were elucidated by spectral techniques (MS, 1H NMR, 13C NMR, HSQC, HMBC, DEPT, and TOCSY) and were compared with data reported in literature, and were established as 2 S*,2′ R*,3 S*,4 R*,11 E)- N-[2′-hydroxyhenicosanoyl]-2-amino-nonadec-11-ene-1,3,4-triol (1) and (2 S*,2′ R*,3 S*,4 R*,8 E)- N-[2′-hydroxytricosanoyl]-2-amino-nonadec-8-ene-1,3,4-triol (2). To establish the structure and to locate the double bond, the methyl ester of the fatty acid and dimethyl disulfide (DMDS) derivatives were prepared for both ceramides.

2015 ◽  
Vol 21 (5) ◽  
pp. 269-272 ◽  
Author(s):  
Snehal A. Chavan ◽  
Avinash G. Ulhe ◽  
Baliram N. Berad

AbstractNew 4,7-bis(arylamino)-2-tetra-O-acetyl-β-d-glucopyranosylimino-1,3,5,6-dithiadiazepines were synthesized via reaction of N-tetra-O-acetyl-β-d-glucopyranosyl isocyanodichloride with 1,6-diaryl-2,5-dithio-bis-ureas without using any catalyst. Thus, the synthesis of 7-membered heterocycles containing two sulfur and two nitrogen atoms through carbon-sulfur bond formation was explored. The chemical structures of these new compounds were elucidated by IR, 1H NMR, 13C NMR, mass spectral, and elemental analyses.


2009 ◽  
Vol 6 (3) ◽  
pp. 928-937 ◽  
Author(s):  
D. Srividhya ◽  
S. Manjunathan ◽  
S. Thirumaran

This investigation enumerates the synthesis and mesomorphic properties of 1,2,3-triazole containing azobenzene liquid crystals. In these liquid crystals the methylene chain length at non polar end was varied from six to ten carbons to investigate the association properties of non polar chain on the melt. The compound was designed to have a polar ether chain at the other side of the molecule adjacent to the triazole ring and synthesized to enhance the dipolar interactions. These alterations in chemical structure produce two series of new liquid crystalline compounds with each series containing five variations in the methylene chain. The structure of the target compounds and the intermediates were confirmed by the1H NMR,13C NMR and IR spectral techniques. Polarized microscopic studies revealed that all the compounds in the series exhibited enantiotropic liquid crystalline properties. This was further confirmed using differential scanning calorimetric experiments. The energy minimized structure supports the mesogenic behavior of the structure.


2001 ◽  
Vol 05 (04) ◽  
pp. 367-375 ◽  
Author(s):  
S. ZEKİ YILDIZ ◽  
HALTİ KANTEKİN ◽  
YAŞAR GÖK

New metal-free 5 and metallophthalocyanines 6-11( M = Cu , Ni , Co , Pb , Zn ) fused in peripheral positions with four 24-membered tetraoxatetraaza macrocycles were prepared by cyclotetramerization of 24,25-dicyano-4,10,13,17-tetra(toluene-p-sulfonyl)-1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22-didicontinehydrobenzo[y][3,9,12,18]tetraaza[1,7,16,22]tetraoxatetradicontine in the presence of the corresponding metal salt or a strong organic base. While the N-tosylated derivatives of the phthalocyanines are soluble in common organic solvents, the detosylated derivative of copper phthalocyaninate is soluble in water. The aggregation properties of the phthalocyanines were also investigated as a function of concentration, solvent and oxidative medium. The new compounds are characterized by a combination of elemental analysis and 1 H NMR, 13 C NMR, IR, UV-vis and MS spectral data.


2020 ◽  
Author(s):  
Gashaw Nigussie

Abstract Rumex nervosus belongs to the family of Polygonaceae,which is traditionally used in Ethiopia to treat various diseases. This prompted us to isolate bioactive compounds from the root of this plant. Ground root parts of Rumex nervosus were subjected to exhaustive extraction successively with petroleum ether and methanol.The solvent from each extract was evaporated under reduced pressure using rotavapour to obtain petroleum ether and methanol extract. Chromatographic purification of the methanol extracts by Column chromatography followed by Preparative Thin layer Chromatography using Chloroform: methanol (9.5:0.5) ratio gave a compound coded as RN-6. The structure of this compound 4-ethylheptyl benzoate was characterized as by means of 1H NMR, 13C NMR, UV and IR spectral data.


2019 ◽  
Vol 44 (3-4) ◽  
pp. 148-151
Author(s):  
Volkan Çakır

In this study, a new phthalonitrile derivative, ( E)-4-(3-(3-(3-methoxyphenyl)acryloyl)phenoxy)phthalonitrile, and four peripherally ( E)-4-(3-(3-(3-methoxyphenyl)acryloyl)phenoxy) tetrasubstituted new Ni(II), Zn(II), Co(II), and Cu(II) phthalocyanine derivatives are synthesized and characterized. ( E)-4-(3-(3-(3-Methoxyphenyl)acryloyl)phenoxy)phthalonitrile is synthesized by heating ( E)-1-(3-hydroxyphenyl)-3-(3-methoxyphenyl)prop-2-en-1-one and 4-nitrophthalonitrile in the presence of K2CO3 in dry DMF at 60°C for 96 h. The metallophthalocyanines are prepared by cyclotetramerization of ( E)-4-(3-(3-(3-methoxyphenyl)acryloyl)phenoxy)phthalonitrile with NiCl2, Zn(CH3COO)2, CoCl2, and CuCl2 in n-pentanol in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene. Characterization of the new compounds is performed by means of IR, 1H NMR, 13C NMR, and mass and UV-Vis spectroscopy techniques.


2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Chuanjiang Li ◽  
Hui Wang ◽  
Manuel Juárez ◽  
Eric Dongliang Ruan

Maillard reaction is a nonenzymatic reaction between reducing sugars and free amino acid moieties, which is known as one of the most important modifications in food science. It is essential to characterize the structure of Amadori rearrangement products (ARPs) formed in the early stage of Maillard reaction. In the present study, the Nα-acetyl-lysine-glucose model had been successfully set up to produce ARP, Nα-acetyl-lysine-glucose. After HPLC purification, ARP had been identified by ESI-MS with intense [M+H]+ ion at 351 m/z and the purity of ARP was confirmed to be over 90% by the relative intensity of [M+H]+ ion. Further structural characterization of the ARP was accomplished by using nuclear magnetic resonance (NMR) spectroscopy, including 1D 1H NMR and 13C NMR, the distortionless enhancement by polarization transfer (DEPT-135) and 2D 1H-1H and 13C-1H correlation spectroscopy (COSY) and 2D nuclear overhauser enhancement spectroscopy (NOESY). The complexity of 1D 1H NMR and 13C NMR was observed due to the presence of isomers in glucose moiety of ARP. However, DEPT-135 and 2D NMR techniques provided more structural information to assign the 1H and 13C resonances of ARP. 2D NOESY had successfully confirmed the glycosylated site between 10-N in Nα-acetyl-lysine and 7′-C in glucose.


2012 ◽  
Vol 9 (3) ◽  
pp. 1518-1525 ◽  
Author(s):  
Hamid Reza Jaberi ◽  
Hadi Noorizadeh

In this work we describe the synthesis of some novel fused imidazo [2, 1-b] [1, 3] thiazole derivatives. The reaction of 1, 2-diaminoethane 1 with carbon disulphide in H2O/ETOH as solvent furnishes 4, 5-dihydro-1H-imidazol-2-thiol 2 under reflux condition. the reaction of 4,5-dihydro-1H-imidazol-2-thiol on treatment with ethylchloro acetate and aromatic aldehyde in presence of anhydrous sodium acetate and acetic acid as solvent to give (Z)-2-(arylidene)-5,6-dihydroimidazo [2,1-b] [1,3] thiazol-3(2H)-one 3a-j. Compounds 3a-j was condensed with hydroxylamine to give 3-(aryl)-2, 3, 6, 7-tetrahydroimidazo [2, 1-b] [1,3] thiazolo [5, 4-d] isoxazole 4a-j. The structures of the new compounds were established by elemental analyses, IR,1H NMR and13C NMR data.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Farooq Azam ◽  
Bashir Ahmad Chaudhry ◽  
Hira Ijaz ◽  
Muhammad Imran Qadir

Abstract This study evaluates the antioxidant activity of Ranunculus muricatus and isolation and structure elucidation of the active constituents. The aerial parts of the plants were shade dried at room temperature and powdered and extracted with methanol. The free radical scavenging activity was evaluated by 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay. The percentage scavenging activity was determined based on the percentage of DPPH radical scavenged. Column chromatography was used in order to isolate the active compounds. Spectral techniques UV, IR, 1H NMR, 13CNMR and HREI-MS were used for the structure elucidation of the isolated compounds. Two isolated compounds, A (caffeoyl-β-d-glucopyranoside) and B (1,3-dihydroxy-2-tetracosanoylamino-4-(E)-nonadecene), exibited a significant antioxidant activity as showed by DPPH radical scavenging method. Percentage inhibition for compound A (at 0.5 mM) was 82.67 ± 0.19 with IC50 of 93.25 ± 0.12 (μM), and for compound B (at 0.5 mM) was 69.23 ± 0.19 with IC50 of 183.34 ± 0.13 (μM). Quercetin was used as standard control. It was conclued from the present study that caffeoyl-β-d-glucopyranoside and 1,3-dihydroxy-2-tetracosanoylamino-4-(E)-nonadecene isolated from methanol extract of aerial parts of Ranunculus muricatus posses antioxidant activity.


2006 ◽  
Vol 61 (11) ◽  
pp. 1437-1442 ◽  
Author(s):  
Iris Djordjević ◽  
Milka Jadranin ◽  
Vlatka Vajs ◽  
Nebojša Menković ◽  
Vele Tešević ◽  
...  

The aerial parts of Amphoricarpos neumayeri ssp. murbeckii afforded eleven guaianolides with the same relative (1αH,4β H,5αH,7αH) configuration of the basic skeleton. All of them contained a CH2OX (X = H, acetyl or isovaleroyl) group in 4α-position, typical for amphoricarpolides. Four compounds (1 - 4) were isolated before from the same species, originating from different localities. Guaianolides 5 - 11 are new compounds. Compounds 7 and 8 were epoxidized at the 10α(14)-position. Instead of the Δ11(13)-double bond, observed in all previously isolated guaianolides from the same species, the four lactones contained 11α,13-diol (8 - 10) or 11α-OH,13-chloro (11) moieties respectively.


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