scholarly journals Zur Reaktivität von C=N Doppelbindungssystemen, II / The Reactivity of the C=N Double Bond Systems, II

1975 ◽  
Vol 30 (3-4) ◽  
pp. 245-248 ◽  
Author(s):  
Georg Uray ◽  
Erich Ziegler
Keyword(s):  
Double Bond ◽  
Schiff Bases ◽  
Uv Spectroscopy ◽  
H Nmr ◽  
Real Addition ◽  
Spectroscopic Behavior ◽  
C Nmr

The adducts from carboxylicacid chlorides and -anhydrides of aromatic Schiff-Bases differ fundamentally in their spectroscopic behavior compared with the hydrochlorides. A real addition on the azomethine double-bond is shown by 1H NMR, 13C NMR and UV spectroscopy.

Tautomeric Study of Schiff Bases Derived from o ‐Dihydroxybenzaldehyde by UV‐Vis, IR, 1 H NMR, 13 C NMR Spectroscopy and Computational Modeling.

2020 ◽  
Vol 5 (36) ◽  
pp. 11120-11126
Author(s):  
Carmen María Atzin‐Macedo ◽  
Cándida Pastor‐Ramírez ◽  
Rafael González‐Peláez ◽  
Francisco Javier Pérez‐Flores ◽  
Samuel Hernández‐Anzaldo ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Computational Modeling ◽  
Schiff Bases ◽  
H Nmr ◽  
C Nmr

A contribution to peroxy acid oxidation of α,β-unsaturated ketones and linearly conjugated dienones: Reactions in the cholestane series

1988 ◽  
Vol 53 (7) ◽  
pp. 1549-1567 ◽  
Author(s):  
Václav Černý ◽  
Miloš Buděšínský ◽  
Miloš Ryba ◽  
František Tureček
Keyword(s):  
Double Bond ◽  
Carbonyl Group ◽  
Acid Oxidation ◽  
Peroxy Acid ◽  
Unsaturated Ketones ◽  
H Nmr ◽  
Nmr Data ◽  
Epoxy Ketones ◽  
C Nmr

Oxidation with 3-chloroperoxybenzoic acid of s-cis α,β-unsaturated ketones IX, XI and s-trans types X, XII was compared. The s-cis ketones show higher reactivity and furnish a higher yield of the corresponding α,β-epoxy ketones than the s-trans ketones. Products of the Baeyer-Villiger reaction are formed only in low yield. The dienone VI is oxidized predominantly to VII thus violating the rule that linear conjugated dienones are epoxidized at the double bond more distant from the carbonyl group; this result is in accord with the behaviour of s-cis α,β-unsaturated ketones. 1H NMR and 13C NMR data of the starting compounds and of the products are reported.

Steroids with the β-crotonate (2-butenoate) side chain

1986 ◽  
Vol 51 (1) ◽  
pp. 128-140 ◽  
Author(s):  
Ivan Černý ◽  
Vladimír Pouzar ◽  
Pavel Drašar ◽  
František Tureček ◽  
Miroslav Havel
Keyword(s):  
Double Bond ◽  
Nmr Spectroscopy ◽  
Lithium Salt ◽  
Side Chain ◽  
H Nmr ◽  
C Nmr

Ethyl (20E)-3β-methoxymethoxy-24-nor-5,20(22)-choladien-23-oate (Va) and analogous derivatives with 5α,5β and Δ5,14 steroid moiety (Vb,Vc and Vd, respectively) were prepared by Wittig-Horner reaction of the corresponding ketones IIa-IId with diethyl ethoxycarbonylmethylphosphonate. In this case the reaction affords exclusively the (E)-isomers, in contrast with the Peterson reaction with lithium salt of ethyl 2-(trimethylsilyl)acetate which gives a mixture of (E)- and (Z)-isomers at the Δ20(22) double bond. The structure of the products was confirmed by 1H NMR and 13C NMR spectroscopy. The crotonates Va-Vd were further converted into the 3-O-succinyl derivatives VIIIa-VIIId.

scholarly journals A semisynthesis of 3'-O-ethyl-5,6-dihydrospinosyn J based on the spinosyn A aglycone

2017 ◽  
Vol 13 ◽  
pp. 2603-2609 ◽  
Author(s):  
Kai Zhang ◽  
Shenglan Liu ◽  
Anjun Liu ◽  
Hongxin Chai ◽  
Jiarong Li ◽  
...  
Keyword(s):  
Double Bond ◽  
Chemical Synthesis ◽  
Minor Component ◽  
Food Storage ◽  
Selective Protection ◽  
H Nmr ◽  
High Yields ◽  
Agriculture And Food ◽  
Hydrolysis Of ◽  
C Nmr

Spinetoram, a mixture of 3'-O-ethyl-5,6-dihydrospinosyn J (XDE-175-J, major component) and 3'-O-ethylspinosyn L (XDE-175-L, minor component), is a novel kind of green and efficient insecticide with a broad range of action against various insects. Nowadays, spinetoram is widely used in agriculture and food storage. This work reports a 7-step semisynthesis of 3'-O-ethyl-5,6-dihydrospinosyn J from spinosyn A aglycone. The C9–OH and C17–OH of the aglycone are successively connected to 3-O-ethyl-2,4-di-O-methylrhamnose and D-forosamine after selective protection and deprotection steps. Then, with 10% Pd/C as catalyst, the 5,6-double bond of the macrolide was selectively reduced to afford 3'-O-ethyl-5,6-dihydrospinosyn J. In addition, the 3-O-ethyl-2,4-di-O-methylrhamnose is synthesized from rhamnose which is available commercially, while the D-forosamine and aglycone are obtained via the hydrolysis of spinosyn A. High yields were obtained in each step, and all intermediates in the synthesis were characterized by 1H NMR, 13C NMR and MS techniques. This study can be helpful for developing an efficient chemical synthesis of spinetoram, and it also offers opportunities to synthesize spinosyn analogues and rhamnose derivatives.

scholarly journals Synthesis, Characterization and Antibacterial Activity of Novel Schiff Bases Derived from 4-Phenyl-2-aminothiazole and their Mn(II), Fe(II), Co(II), Ni(II) and Cu(II) Metal complexes

2011 ◽  
Vol 8 (4) ◽  
pp. 1556-1565 ◽  
Author(s):  
A. S. Thakar ◽  
K. S. Pandya ◽  
K. T. Joshi ◽  
A. M. Pancholi
Keyword(s):  
Antibacterial Activity ◽  
Metal Complexes ◽  
Schiff Bases ◽  
Mass Spectra ◽  
Uv Spectra ◽  
Assay Method ◽  
H Nmr ◽  
Ft Ir ◽  
Schiff Base Metal Complexes ◽  
C Nmr

Novel Schiff bases and their metal complexes were derived from some hetero cyclicβ-diketones with 4-phenyl-2-aminothiazole. All the synthesized compounds were confirmed their structure by Elemental analysis, FT-IR,1H NMR,13C NMR, Mass spectra, TGA analysis and UV spectra. All the compounds were tested for their antibacterial activity. Spectroscopic measurements suggest that all Schiff base metal complexes are of type ML2.(H2O)2(M=Mn, Fe, Co, Ni and Cu) and all the metal complexes shows moderate antibacterial activity in the agar cup assay method.

scholarly journals Synthesis, Characterization and Antibacterial Activity of Schiff Bases and their Metal Complexes Derived from 4-Acyl-1-phenyl-3-methyl-2-pyrazolin-5-ones and 2-Amino-4(4'-methylphenyl)-thiazole

2010 ◽  
Vol 7 (4) ◽  
pp. 1396-1406 ◽  
Author(s):  
A. S. Thakar ◽  
K. K. Singh ◽  
K. T. Joshi ◽  
A. M. Pancholi ◽  
K. S. Pandya
Keyword(s):  
Antibacterial Activity ◽  
Schiff Bases ◽  
Elemental Analysis ◽  
Mass Spectra ◽  
Nmr Spectra ◽  
Electrical Conductance ◽  
H Nmr ◽  
Infrared Spectral ◽  
Ft Ir ◽  
C Nmr

4-Acyl-1-phenyl-3-methyl-2-pyrazolin-5-ones condensed with 2-amino-4(4'-methylphenyl)-thiazole to form Schiff base. These Schiff bases from complexes of type ML22H2O (M=Mn, Fe, Co, Ni and Cu). Elemental analysis, magnetic susceptibility, electrical conductance, electronic and Infrared spectral data suggested octahedral structure for the complexes. All the compounds were tested for their antibacterial activity. The result indicates that the growth of the tested organism was inhibited by most of the compounds. These Schiff bases are characterized by elemental analysis, mass spectra,1H-NMR spectra,13C NMR spectra and FT IR spectra.

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 ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Double Bond ◽  
Dimethyl Disulfide ◽  
Spectral Techniques ◽  
H Nmr ◽  
Aerial Parts ◽  
Isolation And Characterization ◽  
New Compounds ◽  
C Nmr

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.

scholarly journals Nucleobase-Based Barbiturates: Their Protective Effect against DNA Damage Induced by Bleomycin-Iron, Antioxidant, and Lymphocyte Transformation Assay

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Bhaveshkumar D. Dhorajiya ◽  
Bharatkumar Z. Dholakiya ◽  
Ahmed S. Ibrahim ◽  
Farid A. Badria
Keyword(s):  
Dna Damage ◽  
Protective Effect ◽  
Uv Spectroscopy ◽  
Lymphocyte Transformation ◽  
High Yield ◽  
One Pot ◽  
H Nmr ◽  
Transformation Assay ◽  
Ft Ir ◽  
C Nmr

A number of nucleobase-based barbiturates have been synthesized by combination of nucleic acid bases and heterocyclic amines and barbituric acid derivatives through green and efficient multicomponent route and one pot reaction. This approach was accomplished efficiently using aqueous medium to give the corresponding products in high yield. The newly synthesized compounds were characterized by spectral analysis (FT-IR,1H NMR,13C NMR, HMBC, and UV spectroscopy) and elemental analysis. Representative of all synthesized compounds was tested and evaluated for antioxidant, bleomycin-dependent DNA damage, and Lymphocyte Transformation studies. CompoundsTBC>TBA>TBGshowed highest lymphocyte transformation assay,TBC>TBA>BGshowed inhibitory antioxidant activity using ABTS methods, andTBC>BPA>BAMT>TBA>1,3-TBAmanifested the best protective effect against DNA damage induced by bleomycin.

scholarly journals N-alkyl-N-(phosphonoethyl) substituted (meth)acrylamides – new adhesive monomers for self-etching self-priming one part dental adhesive

2009 ◽  
Vol 5 ◽  
Author(s):  
Joachim E Klee ◽  
Uwe Lehmann
Keyword(s):  
Refractive Index ◽  
Double Bond ◽  
Nmr Spectroscopy ◽  
Hydrolytic Stability ◽  
Dental Adhesive ◽  
H Nmr ◽  
Acrylamide Monomers ◽  
Carboxylic Esters ◽  
C Nmr

Novel N-alkyl-N-(phosphonoethyl) substituted mono-, bis- and tris(meth)acrylamides 3 were synthesized by two different three-step reactions and characterized by IR, 1H NMR and 13C NMR spectroscopy as well as refractive index and viscosity. The phosphonoethyl substituted (meth)acrylamide monomers show improved hydrolytic stability compared to carboxylic esters. The highest stability was found for the phosphonoethyl substituted acrylamide monomers. Acrylamides have a larger polymerization enthalpy ranging from −50 to −70 kJ·mol−1 per double bond compared to methacrylamides which show −8.57 to −25.1 kJ·mol−1 per double bond. Depending on their structure (meth)acrylamides 3 exhibit an adhesion to enamel and dentin up to 19.5 MPa. The monomer 3c shows the highest adhesion values to both substrates, namely 15.3 ± 3.4 MPa to enamel and 18.5 ± 2.3 MPa to dentin.

1H and 13C NMR study of some substituted 2-furyl- and 2-thienylethylene derivatives

1986 ◽  
Vol 51 (4) ◽  
pp. 889-898 ◽  
Author(s):  
Miloslava Dandárová ◽  
Daniel Végh ◽  
Jaroslav Kováč ◽  
Igor Goljer ◽  
Nadežda Prónayová ◽  
...  
Keyword(s):  
Double Bond ◽  
Heterocyclic Ring ◽  
Coupling Constants ◽  
Side Chain ◽  
1H And 13C Nmr ◽  
H Nmr ◽  
Nmr Data ◽  
Nmr Study ◽  
Thiophene Derivatives ◽  
C Nmr

The 1H and 13C NMR spectral data of 1-(5-nitro-2-furyl)-2-X-2-Y-ethylenes and some their thienyl analogues are presented. Geometrical arrangement of the trisubstituted ethylenes was adduced from vicinal coupling constants 3J(C, H) for the carbon atom at the functional group attached to the double bond and the ethylene proton. The orientation of the heterocyclic ring towards the double bond of the side chain was determined from the 1H NMR data. The preferred s-cis or s-trans conformations of 5-nitro-2-furylethylene derivatives is substituent at the double bond dependent; all thiophene derivatives under study were found in the s-trans conformation.

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