Hydrazine Derivatives of β-Dicarbonyl Compounds, Part I. Studies on Some Benzoylacetaldehyde Aroylhydrazones

1978 ◽  
Vol 33 (12) ◽  
pp. 1527-1534 ◽  
Author(s):  
Latif Rateb ◽  
B. Azmy ◽  
M. A. Nashed ◽  
M. F. Iskander
Keyword(s):  
Schiff Bases ◽  
Nmr Spectra ◽  
Open Chain ◽  
Dicarbonyl Compounds ◽  
Hydrazine Derivatives ◽  
H Nmr ◽  
Imine Form ◽  
Derivatives Of

Abstract A series of benzoylacetaldehyde benzoylhydrazones were prepared and characterised. Their UV, IR, and 1H NMR spectra suggest the enol-imine structure rather than the keto-imine form of analogous Schiff bases. The pKa values of these aroylhydrazones were also measured and correlated with the Hammet substitution constants. Attempted cyclizations of these open-chain aroylhydrazones afforded the corresponding 5-hydroxy-2-pyrazoline compounds rather than the expected pyrazoles.

Morpholines-(IV)

1971 ◽  
Vol 26 (11) ◽  
pp. 1140-1143 ◽  
Author(s):  
Riaz F. Abdulla ◽  
Alok N. Bannerji
Keyword(s):  
Nmr Spectroscopy ◽  
Nmr Spectra ◽  
Beta Lactams ◽  
Aryl Substituent ◽  
Open Chain ◽  
H Nmr

Cyclodehydrohalogenation-beta-Lactams-Morpholin-3-ones-H'-NMR SpectroscopyN-Aryl-N-chloroacetyl-2-chlorophenacylamines (2) give morpholinones 3, or beta-lactams 4, depending upon the N-aryl-substituent. N-Phenyl-N- (2,3-dibromo-3-phenylpropionyl) -4-nitrophenacylamine did not undergo base-catalysed cyclization but gave, instead, the α,β-unsaturated, open-chain amide 5. N-Aryl-N-chloroacetyl-aminomethyl-2-naphthylketones afford only beta-lactams. The first attempt at the synthesis of a 2-chloro-3-oxo-morpholine resulted in the isolation of the 2-hydroxyderivative. The H1-NMR spectra of some more 3-oxo-morpholines have been recorded.

Photoreaktionen von Dekacarbonyldirhenium mit Allen und unverzweigten Allenderivaten / Photoreactions of Decacarbonyldirhenium with Allene and Unbranched Derivatives of Allene

1995 ◽  
Vol 50 (4) ◽  
pp. 649-660 ◽  
Author(s):  
Cornelius G. Kreiter ◽  
Wolfgang Michels ◽  
Gerhard Heeb
Keyword(s):  
Nmr Spectra ◽  
Crystal And Molecular Structure ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Oxidative Rearrangement ◽  
Dirhenium Complexes ◽  
Derivatives Of ◽  
By Products

Decacarbonyldirhenium (1) reacts upon UV irradiation with allene (2), 1,2-butadiene (3) and 2,3-pentadiene (4) preferentially by CO substitution and oxidative rearrangement to the corresponding enneacarbonyl-μ-η1:3-endiyl-dirhenium complexes 5, 9, and 15 and to the octacarbonyl-μ-η2:2-allene-dirhenium complexes 6, the stereoisomers 10, 11, and 16. At elevated temperature 5, 9, and 15 loose CO and yield by a reductive rearrangement also the complexes 6, 10, 11, and 16. In addition to these main products, depending upon the allene derivative used, various by-products are obtained.By-products of the reaction o f 1 with 2 are octacarbonyl-μ-η3:3-(2,3-dimethylene-buta-1,4- diyl)dirhenium (7) and μ-η2:2-allene-hexacarbonyl-μ-η1:3-1-propene-1,3-diyl-dirheniurn (8). The photo reaction of 1 with 3 yields, in addition to 9-11, tetracarbonyl-η3-(E-5-ethylidene- 4-methyl-2-cyclopenten-1-yl)rhenium (12) and tetracarbonyl-η3-(Z-5-ethyliden-4- methyl-2-cyclopenten-1-yl)rhenium (13) as a mixture of isomers. 1 and 4 form the by-products tetracarbonyl-η3-(EZ-3-penten-2-yl)rhenium (17), tetracarbonyl-η3-(EE-3-penten-2-yl)rhenium (18) and heptacarbonyl-μ-η1:2:1:2-(4,5-dimethyl-2,6-octadiene-3,6-diyl)dirhenium (19) with an unusually bridging and chelating ligand. The constitutions of the reaction products have been concluded from the IR and 1H NMR spectra. For 19 the crystal and molecular structure has been determined by X-ray diffraction analysis.

Synthesis of Optically Active N6-Alkyl Derivatives of (R)-3-(Adenin-9-yl)-2-hydroxypropanoic Acid and Related Compounds

2003 ◽  
Vol 68 (5) ◽  
pp. 931-950 ◽  
Author(s):  
Marcela Krečmerová ◽  
Miloš Buděšínský ◽  
Milena Masojídková ◽  
Antonín Holý
Keyword(s):  
Nmr Spectra ◽  
Enantiomeric Purity ◽  
Optically Active ◽  
Secondary Amines ◽  
H Nmr ◽  
Alkyl Derivatives ◽  
Optically Pure ◽  
Derivatives Of ◽  
Related Compounds

Reaction of ethyl (R)-oxiranecarboxylate (2a) with various nucleobases (adenine, 6-chloropurine, thymine, cytosine, N6-benzoyladenine, 4-methoxy-5-methylpyrimidin-2(1H)-one and 4-methoxypyrimidin-2(1H)-one) afforded ethyl 3-substituted-2-hydroxypropanoates 4-10. Enantioselectivity of this reaction is dependent on the type of the base: 6-chloropurine, N6-benzoyladenine, 4-methoxy-5-methylpyrimidin-2(1H)-one, thymine and cytosine gave optically pure R enantiomers. In other cases, partial or complete racemization occurred. Optically pure ethyl (R)-3-(6-chloropurin-9-yl)-2-hydroxypropanoate (5a) was hydrolyzed to give (R)-3-(6-chloropurin-9-yl)-2-hydroxypropanoic acid (11). Reactions of 11 with various primary or secondary amines led to N6-substituted (R)-3-(adenin-9-yl)-2-hydroxypropanoic acids 14-19. Enantiomeric purity was determined from 1H NMR spectra measured in the presence of (-)-(R)-1-(9-anthryl)-2,2,2-trifluoroethan-1-ol.

scholarly journals Synthesis and biological evaluation of new Benzimidazole derivatives

2018 ◽  
Vol 29 (1) ◽  
pp. 107 ◽  
Author(s):  
Hadeel Majed ◽  
Firyal W. Askar
Keyword(s):  
Schiff Bases ◽  
Nmr Spectra ◽  
Antimicrobial Activities ◽  
Biological Evaluation ◽  
Benzimidazole Derivatives ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
H Nmr ◽  
Bacteria And Fungi ◽  
Synthesis And Biological Evaluation

Agroup of benzimidazole derivatives bearing different heterocyclic moieties such as Schiff bases, 2-azetidinone and  4-thiazolidinone were efficiently prepared. The structures of the newly compounds were characterized by FTIRand ¹H NMR spectra. The synthesized compounds were evaluated for their antimicrobial activities against gram-positive and gram negative bacteria and fungi using the microdilution procedure.

Purine Nucleoside Analogues. 11. An Alternative Synthesis of N- and O-Alkyl Derivatives of 9- and 7-[(2-Acetoxyethoxy)methyl]-N2-acetylguanine

1999 ◽  
Vol 64 (4) ◽  
pp. 685-695 ◽  
Author(s):  
Marina Madre ◽  
Natella Panchenko ◽  
Alexander Golbraikh ◽  
Regina Zhuk ◽  
Upendra K. Pandit ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Room Temperature ◽  
Purine Nucleoside ◽  
Nucleoside Analogues ◽  
Alternative Synthesis ◽  
Restricted Rotation ◽  
H Nmr ◽  
Alkyl Derivatives ◽  
Derivatives Of ◽  
Conformational Calculations

Alkylations of 9- and 7-[(2-acetoxyethoxy)methyl]-N2-acetylguanine with alkyl halogenides in the presence of base have been investigated affording a new route to the preparation of 1,N2-dimethyl- as well as O6-benzyl-9(7)-alkoxyalkylguanines. 1H NMR spectra revealed that the 1,N2-dimethyl derivatives exist as mixtures of two conformers at room temperature due to the restricted rotation about the C2-N2 bond. These findings agreed with conformational calculations.

Synthesis of cyclopentane analogs of (2′- and 3′-deoxy-erythro-pentofuranosyl and ribofuranosyl)-2-thiouracil nucleosides

1986 ◽  
Vol 64 (8) ◽  
pp. 1620-1629 ◽  
Author(s):  
Lucjan J.J. Hronowski ◽  
Walter A. Szarek
Keyword(s):  
Sulfur Atom ◽  
Nmr Spectra ◽  
Aqueous Ammonia ◽  
Synthetic Route ◽  
Nmr Spectrum ◽  
H Nmr ◽  
Synthetic Intermediates ◽  
Derivatives Of ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

Three new carbocyclic analogs of nucleosides having the 2-thiouracil base have been synthesized. The cyclopentyl groups in these nucleosides are (±)-{(1β,3α,4β)-3-hydroxy-4-(hydroxyrnethyl)cyclopentyl} (see 31), (±)-{(1β,2α,4β)-2-hydroxy-4-(hydroxymethyl)cyclopentyl} (see 32), and (±)-{(1β,2α,3α,4β)-2,3-dihydroxy-4-(hydroxymethyl)cyclopentyl} (see 33). The nucleosides were prepared by coupling the appropriate hydroxy derivatives of cis-3-aminocyclopentanemethanol with 3-ethoxypropenoyl isothiocyanate (21) followed by cyclization in 15 N aqueous ammonia to give the 2-thiouracil nucleosides. In addition a modified and shortened synthetic route is described for the synthesis of (±)-(1β,2α,3α,4β)-4-amino-2,3-dihydroxy-cyclopentanemethanol (19). The 1H nmr spectra at 200 MHz of all of the synthetic intermediates, the 2-thiouracil nucleosides, and of the corresponding carbocyclic analogs of uracil nucleosides are discussed. It is shown that each nucleoside has a characteristically unique 1H nmr spectrum and that in general the protons in the sulfur-containing compounds resonate at lower fields than those in the corresponding oxygen-containing compounds. The magnitude of this downfield shift is inversely related to the number of bonds separating a particular proton from the sulfur atom.

Epimeric 17-hydroxy derivatives of 14β-androst-5-en-3β-yl acetate

1990 ◽  
Vol 55 (10) ◽  
pp. 2510-2520 ◽  
Author(s):  
Ivan Černý ◽  
Vladimír Pouzar ◽  
Miloš Buděšínský ◽  
Pavel Drašar ◽  
Miroslav Havel
Keyword(s):  
Sodium Nitrite ◽  
Sodium Borohydride ◽  
Nmr Spectra ◽  
H Nmr ◽  
Derivatives Of ◽  
Androstane Derivatives

A new, six-step synthesis of 3β-hydroxy-14β-androst-5-en-17-one (IX) starting from 3β-hydroxyandrost-5-en-17-one has been elaborated. Reduction of acetate X with sodium borohydride afforded 17α-hydroxy-14β-androst-5-en-3β-yl acetate (XI). The corresponding 17β-derivative XIV was obtained by epimerization of 17α-O-tosyl derivative XIII with sodium nitrite in hexamethylphosphoramide. The 13C and 1H NMR spectra of 14β-androstane derivatives are discussed.

Coordination compounds of indium. Part 44. The oxidation of indium(I) halides by tetrahalogeno-ortho-quinones

1988 ◽  
Vol 66 (11) ◽  
pp. 2935-2940 ◽  
Author(s):  
Theodore A. Annan ◽  
Dennis G. Tuck
Keyword(s):  
Coordination Compounds ◽  
Nmr Spectra ◽  
Dynamic Behaviour ◽  
Addition Product ◽  
Donor Ligands ◽  
Chelate Complexes ◽  
H Nmr ◽  
Anionic Complexes ◽  
Derivatives Of ◽  
C Nmr

The reaction of indium(I) halides (InX; X = Cl, Br, I) with tetrahalogeno-ortho-quinones (Y4C6O2; Y = Cl, Br) gives the oxidative addition product Y4C6O2InX, These compounds have been isolated as adducts with neutral bidentate donor ligands (N,N,N′,N′-tetramethylethanediamine (tmen), 1,10-phenanthroline) or as salts of the anionic complexes [Y4C6O2InCl2]− or [Y4C6O2In(Cl)Br]−. The number of coordinated tmen molecules, and hence the structure, depends on the method of preparation. Infrared, 1H NMR, and 13C NMR spectroscopy all confirm that these products are all substituted-catecholato derivatives of indium(III), and the structure of these various neutral or anionic derivatives is discussed. The temperature dependence of the 13C NMR spectra shows that the dynamic behaviour of these compounds (in d6-dmso) is similar to that observed in previous studies of indium(III) chelate complexes.

Trihapto cycloheptatrienyl molybdenum and tungsten dicarbonyl compounds incorporating tridentate chelating dimethyl(1-pyrazolyl)(ethanolamine)gallate ligands

1980 ◽  
Vol 58 (21) ◽  
pp. 2278-2285 ◽  
Author(s):  
Kenneth S. Chong ◽  
Alan Storr
Keyword(s):  
Nitrogen Atom ◽  
Low Temperature ◽  
Physical Properties ◽  
Nmr Spectra ◽  
Room Temperature ◽  
Amino Nitrogen ◽  
Nmr Studies ◽  
Dicarbonyl Compounds ◽  
H Nmr ◽  
And Tungsten

The synthesis and physical properties of a series of cycloheptatrienyl molybdenum and tungsten dicarbonyl compounds incorporating dimethyl(1-pyrazolyl)(ethanolamine)gallate ligands have been investigated. The monomeric, pseudo octahedral, complexes have the organogallate ligand occupying a set of facial positions with the cycloheptatrienyl ring situated opposite to the amino nitrogen atom. Proton nmr studies have shown the η3-C7H7 ligand of the complexes to be fluxional in solution at room temperature. In the low temperature limiting 1H nmr spectra of the complexes in solution, however, it is possible to distinguish ail seven protons of the static η3-C7H7 ring owing to the asymmetric nature of the octahedral molecules.

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