Synthesis of Several Hydroxylated 23-(Benzimidazol-2-yl-, Benzoxazol-2-yl and Benzothiazol-2-yl)norcholanes and Some Related Compounds

The bile acids Ia - Id (lithocholic, chenodeoxycholic, deoxycholic, cholic) and their derivatives (O-acetylated acids and O-acetylated acid chlorides) reacted under various conditions with 1,2-diaminobenzene, 2-aminophenol and 2-aminothiophenol and afforded the title benzimidazoles II and VII, benzoxazoles V and benzothiazoles VI. Alkylation of the benzimidazole derivative IIa with 2-dimethylaminoethyl chloride resulted in 3α-hydroxy-23-[1-(2-dimethylaminoethyl)ben zimidazol-2-yl]- norcholane (IVa). The use of 1,2-diamino-4-methylbenzene enabled the preparation of 3α-acetoxy-23-[5(6)-methylbenzimidazol-2-y l]norcholane (VIII). Reactions of the 3α-hydroxy compounds IVa, Va and VIa with succinic anhydride resulted in the hemisuccinates IVi - VIi. The boric acid mediated condensation of O-acetyllithocholic acid (Ie) with 3,4-diaminopyridine gave compound X which was transformed to 3α-acetoxy-23-[1H-imidazo(4,5- c)pyridin-2-yl]norcholane (IX). The structure of the products was corroborated by the mass, IR, 1H NMR and 13C NMR spectra. Some of the compounds were tested for antileukemic and for the anti-HIV activity in vitro.

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Conformational structure of ethylene glycol dibenzoate. Vibrational and NMR spectra

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811913 ◽

1981 ◽

Vol 46 (8) ◽

pp. 1913-1929 ◽

Cited By ~ 3

Author(s):

Bohdan Schneider ◽

Pavel Sedláček ◽

Jan Štokr ◽

Danica Doskočilová ◽

Jan Lövy

Keyword(s):

Ethylene Glycol ◽

Vibrational Spectra ◽

Nmr Spectra ◽

Coupling Constants ◽

Conformational Structure ◽

Infrared And Raman Spectra ◽

H Nmr ◽

Liquid States ◽

Crystalline Forms ◽

C Nmr

It was found that three crystalline forms of ethylene glycol dibenzoate can be prepared. Infrared and Raman spectra of these three forms, as well as of the glassy and liquid states, were measured. From 3JHH coupling constants obtained by analysis of the 13C satellite band of the -CH2- group in 1H NMR spectra, and from the 3JCH coupling constants of the -CO.O.CH2- fragment obtained by analysis of the carbonyl band in 13C NMR spectra it was found that in the liquid state the -CH2-CH2- group exists predominantly in the gauche conformational structure, and the bonds C-O-C-C assume predominantly a trans orientation. The results of the analysis of NMR and vibrational spectra were used for the structural interpretation of conformationally sensitive bands in vibrational spectra of ethylene glycol dibenzoate.

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Synthesis and Antituberculotic Activity of Some Substituted 3-Arylamino-5-cyano-2-pyrazinecarboxamides

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19951236 ◽

1995 ◽

Vol 60 (7) ◽

pp. 1236-1241 ◽

Cited By ~ 7

Author(s):

Martin Doležal ◽

Jiří Hartl ◽

Antonín Lyčka ◽

Vladimír Buchta ◽

Želmíra Odlerová

Keyword(s):

Nucleophilic Substitution ◽

Elemental Analysis ◽

Nmr Spectra ◽

Substituted Anilines ◽

H Nmr

Nucleophilic substitution of 3-chloro-5-cyano-2-pyrazinecarboxamide by substituted anilines afforded substituted 3-arylamino-5-cyano-2-pyrazinecarboxamides I-X. The structures of compounds were confirmed by elemental analysis, UV, IR and 1H NMR spectra. The assessment of in vitro antimycotic and antimycobacterial activities of the compounds was carried out. The highest antituberculotic activity against M. tuberculosis in this series was shown by 3-anilino- 5-cyano-2-pyrazinecarboxamide (I), whose efficacy was the same as that of pyrazinecarboxamide.

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Synthesis and Structure Assignment of 2-(4-Methoxybenzyl)cyclohexyl β-D-Glucopyranoside Enantiomers

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20061470 ◽

2006 ◽

Vol 71 (10) ◽

pp. 1470-1483 ◽

Cited By ~ 3

Author(s):

David Šaman ◽

Pavel Kratina ◽

Jitka Moravcová ◽

Martina Wimmerová ◽

Zdeněk Wimmer

Keyword(s):

Analytical Data ◽

Chiral Hplc ◽

Nmr Analysis ◽

Target Structure ◽

Enantiomerically Pure ◽

Whole Cells ◽

H Nmr ◽

Structure Assignment ◽

Related Compounds ◽

C Nmr

Glucosylation of the cis- and trans-isomers of 2-(4-methoxybenzyl)cyclohexan-1-ol (1a/1b, 2a/2b, 1a or 2a) was performed to prepare the corresponding alkyl β-D-glucopyranosides, mainly to get analytical data of pure enantiomers of the glucosides (3a-6b), required for subsequent investigations of related compounds with biological activity. One of the employed modifications of the Koenigs-Knorr synthesis resulted in achieving 85-95% yields of pure β-anomers 3a/3b, 4a/4b, 3a or 4a of protected intermediates, with several promoters and toluene as solvent, yielding finally the deprotected products 5a/5b, 6a/6b, 5a or 6a as pure β-anomers. To obtain enantiomerically pure β-anomers of the target structure (3a, 4a, 5a and 6a) for unambiguous structure assignment, an enzymic reduction of 2-(4-methoxybenzyl)cyclohexan-1-one by Saccharomyces cerevisiae whole cells was performed to get (1S,2S)- and (1S,2R)-enantiomers (1a and 2a) of 2-(4-methoxybenzyl)cyclohexan-1-ol. The opposite enantiomers of alkyl β-D-glucopyranosides (5b and 6b) were obtained by separation of the diastereoisomeric mixtures 5a/5b and 6a/6b by chiral HPLC. All stereoisomers of the products (3a-6b) were subjected to a detailed 1H NMR and 13C NMR analysis.

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

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19950619 ◽

1995 ◽

Vol 60 (4) ◽

pp. 619-635 ◽

Cited By ~ 1

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.

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SYNTHESIS AND STRUCTURAL ELUCIDATION OF AMINO ACETYLENIC AND THIOCARBAMATES DERIVATIVES FOR 2-MERCAPTOBENZOTHIAZOLE AS ANTIMICROBIAL AGENTS

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i2.15760 ◽

2017 ◽

Vol 9 (2) ◽

pp. 192

Author(s):

Aseel Alsarahni ◽

Zuhair Muhi Eldeen ◽

Elham Al-kaissi ◽

Ibrahim Al- Adham ◽

Najah Al-muhtaseb

Keyword(s):

Antimicrobial Activity ◽

Elemental Analysis ◽

Antimicrobial Agents ◽

Diffusion Method ◽

Benzothiazole Derivatives ◽

H Nmr ◽

Ft Ir ◽

Potential Antimicrobial Activity ◽

C Nmr

Objective: To design and synthesize amino acetylenic and thiocarbonate of 2-mercapto-1,3-benthiazoles as potential antimicrobial agents.Methods: A new series of 2-{[4-(t-amino-1-yl) but-2-yn-1-yl] sulfanyl}-1,3-benzothiazole derivatives (AZ1-AZ6), and S-1,3-benzothiazol-2-yl-O-alkyl carbonothioate derivatives were synthesised, with the aim that the target compounds show new and potential antimicrobial activity. The elemental analysis was indicated by the EuroEA elemental analyzer, and biological characterization was via IR, 1H-NMR, [13]C-NMR, DSC were determined with the aid of Bruker FT-IR and Varian 300 MHz spectrometer using DMSO-d6 as a solvent. In vitro antimicrobial activity, evaluation was done for the synthesised compounds, by agar diffusion method and broth dilution test. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined. Results: The IR, 1H-NMR, 13C-NMR, DSC and elemental analysis were consistent with the assigned structures. Compound of 2-{[4-(4-methylpiperazin-1-yl)but-2-yn-1-yl] sulfanyl}-1,3-benzothiazole (AZ1), 2-{[4-(2-methylpiperidin-1-yl)but-2-yn-1-yl]sulfanyl}-1,3-benzothiazole (AZ2), 2-{[4-(piperidin-1-yl) but-2-yn-1-yl]sulfanyl}-1, 3-benzothiazole (AZ6), S-1,3-benzothiazol-2-yl-O-ethyl carbonothioate (AZ7), and S-1,3-benzothiazol-2-yl-O-(2-methylpropyl) carbonothioate (AZ9) showed the highest antimicrobial activity against Pseudomonas aeruginosa (P. aeruginosa), AZ-9 demonstrated the highest antifungal activity against Candida albicans (C. albicans), with MIC of 31.25 µg/ml.Conclusion: These promising results promoted our interest to investigate other structural analogues for their antimicrobial activity further.

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A Natural Triglyceride from the Methanol Root Extract of Cyphostemma Adenocaule (Steud. Ex A. Rich.) Wild & R.B.Drumm

10.26434/chemrxiv.13296539 ◽

2020 ◽

Author(s):

Abdulbasit Haliru Yakubu ◽

Iliya Ibrahim ◽

Abdulqadir bukar bababe ◽

Hassan Yesufu ◽

mohammed Garba Tom

Keyword(s):

Mobile Phase ◽

Nmr Spectra ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Solvent System ◽

Root Extract ◽

H Nmr ◽

Signal Peak ◽

Methylene Group ◽

C Nmr

Cyphostemma adenocaule (Steud. ex A. Rich.) is one of the specie plant that belongs to the family vitacea. In this study, Trilinolein was isolated and characterized from the methanol root extract of the plant. Column chromatography over silica gel granules as the stationary phase and eluted with a mobile phase mixture of n-Hex-EtA; EtA-CHCL3 and CHCL3-MeOH with gradient increasing polarity, followed by a second column using saphadex-LH20 and 100% MeOH as stationary and mobile phase vehicle respectively. TLC was developed with EtA 15: CHCL3 8: MeOH 4: H2O 1 as solvent system; sprayed with 10% H2SO4 ,Vanillin-sulphuric acid, and/ or Polyethylene glycol PEG and heat for spot detection and confirmation of bioactive principles. Compound CA1 was obtained and purified with CHCL3 to give a yellow semi-solid compound (0.23g). The 1H-NMR spectra showed 9 different signals; a signal peak of a glycerol (-CH2OCOR-) moiety on the first α-C chain and on the third αʹ-C at 4.143-4.187ppm and 4.296-4.325ppm respectively, while that of a β glycerol (-CHCOR-) at 5.286ppm. Signals of an allylic methylene group at 2.023-2.035ppm, Olefenic hydrogen group at signal peak of 5.362ppm and a diallylic methylene group at signal 2.790ppm were also observed. In the 13C NMR spectra of compound CA1, 57 carbon atoms where observed, multiple signals overlapping at a range of 14.13-34.21ppm corresponding to the aliphatic CH3 (C18), CH2 (C2, C3, C4, C5, C6, C7, C15, C16, and C17) and allylic (C8, C14) carbon atoms. Signals at 127.90-130.24ppm were assigned to the olefienic C atoms (C9, C10, C12, and C13) while signal of 172.87ppm and 173.32ppm were assigned to the carbonyl (C=O) carbon atoms (C1 and C2) respectively (Table 2). Analysis with DEPT-135, H-H COSY, HMBC and HSQC assignments of CA1 augments assignment of signals made for CA1 from 1H-NMR and 13C-NMR and corresponded to that of Trilinolein (<a href="https://pubchem.ncbi.nlm.nih.gov/#query=C57H98O6">C57H98O6</a>, MW 879.4 g/mol). The isolated compound was positive for the acrolein test for triglycerides; fat & oil and had an IC50 of 46.08µg/ml radical scavenging activity.

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Reactions of 3-(p-substituted-phenyl)-5-chloromethyl-1,2,4-oxadiazoles with KCN leading to acetonitriles and alkanes via a non-reductive decyanation pathway

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.14.280 ◽

2018 ◽

Vol 14 ◽

pp. 3011-3017

Author(s):

Akın Sağırlı ◽

Yaşar Dürüst

Keyword(s):

Nmr Spectra ◽

2D Nmr ◽

Synthetic Route ◽

X Ray ◽

H Nmr ◽

2D Nmr Spectra ◽

Tof Ms ◽

C Nmr

The present work describes an unfamiliar reaction of 5-(chloromethyl)-3-substituted-phenyl-1,2,4-oxadiazoles with KCN affording trisubstituted 1,2,4-oxadiazol-5-ylacetonitriles and their parent alkanes, namely, 1,2,3-trisubstituted-1,2,4-oxadiazol-5-ylpropanes. To the best of our knowledge, the current synthetic route leading to decyanated products will be the first in terms of a decyanation process which allows the transformation of trisubstituted acetonitriles into alkanes by the incorporation of KCN with the association of in situ-formed HCN and most likely through the extrusion of cyanogen which could not be detected or isolated. In addition, the plausible mechanisms were proposed for both transformations. The structures of the title compounds were identified by means of IR, 1H NMR, 13C NMR, 2D NMR spectra, TOF–MS and X-ray measurements.

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New Synthetic Routes for 1-Benzyl-1,4,7,10-tetraazacyclododecane and 1,4,7,10-Tetraazacyclododecane-1-acetic Acid Ethyl Ester, Important Starting Materials for Metal-coded DOTA-Based Affinity Tags

Zeitschrift für Naturforschung B ◽

10.1515/znb-2007-0313 ◽

2007 ◽

Vol 62 (3) ◽

pp. 397-406 ◽

Cited By ~ 8

Author(s):

Stephan W. Kohl ◽

Katharina Kuse ◽

Markus Hummert ◽

Herbert Schumann ◽

Clemens Mügge ◽

...

Keyword(s):

Acetic Acid ◽

Ethyl Ester ◽

Nmr Spectra ◽

Acid Ethyl Ester ◽

Affinity Tags ◽

X Ray ◽

H Nmr ◽

Synthetic Routes ◽

New Compounds ◽

C Nmr

Two improved routes to synthesize 1-benzyl-1,4,7,10-tetraazacyclododecane (6) and 1,4,7,10- tetraazacyclododecane-1-acetic acid ethyl ester (11) are described as well as the synthesis of 1-{2-[4-(maleimido-N-propylacetamidobutyl)amino]-2-oxoethyl}-1,4,7,10-tetraazacyclododecane- 4,7,10-triacetic acid (17) and its Y, Ho, Tm, and Lu complexes. The 1H and 13C NMR spectra of the new compounds as well as the single crystal X-ray structure analyses of the intermediates 4-benzyl-1,7-bis(p-toluenesulfonyl)diethylenetriamine (3) and 1,4,7-tris(p-toluenesulfonyl)diethylenetriamine (7) are reported and discussed. The rare earth complexes of 17 have been characterized by 1H NMR spectroscopy and MALDI-TOF mass spectrometry.

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A New Bioactive Steroidal Saponin from Leaves of Furcraea gigantea

Zeitschrift für Naturforschung B ◽

10.1515/znb-2006-0916 ◽

2006 ◽

Vol 61 (9) ◽

pp. 1153-1157 ◽

Cited By ~ 2

Author(s):

Bernadete P. da Silva ◽

José P. Parente

Keyword(s):

Nmr Spectra ◽

Capillary Permeability ◽

Structural Identification ◽

2D Nmr ◽

In Vitro Assays ◽

Steroidal Saponin ◽

Spectroscopic Techniques ◽

C Nmr

Abstract A new bidesmosidic furostanol saponin was isolated from leaves of Furcraea gigantea Vent. Its structure was established as 3-[(O-6-deoxy-α-L-mannopyranosyl-(1→4)-O-β -D-glucopyranosyl-( 1→3)-O-[O-β -D-glucopyranosyl-(1→3)-β -D-glucopyranosyl-(1→2)-O-β -D-glucopyranosyl- (1→4)-β -D-galactopyranosyl)oxy]-(3β ,5α,15α,22α,25R)-26-(β -D-glucopyranosyloxy)-15,22-dihydroxy- furost-12-one. Its structural identification was performed using detailed analyses of 1H and 13C NMR spectra including 2D NMR spectroscopic techniques (DEPT, COSY, HETCOR and COLOC) and chemical conversions. The steroidal saponin showed no haemolytic effects in the in vitro assays and demonstrated inhibition of the capillary permeability activity.

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Direct observation of low spin – high spin electronic ground states and cross-over exchange in manganocene derivatives, (η5-C5H4R)2Mn, R = H, CH3, C2H5 by paramagnetic nuclear magnetic resonance

Canadian Journal of Chemistry ◽

10.1139/v86-014 ◽

1986 ◽

Vol 64 (1) ◽

pp. 71-75 ◽

Cited By ~ 14

Author(s):

Daniel Cozak ◽

François Gauvin ◽

Jacques Demers

Keyword(s):

Nmr Spectra ◽

Spin Exchange ◽

Exchange Process ◽

Paramagnetic Species ◽

Temperature Range ◽

H Nmr ◽

Low Field ◽

Spin Electronic ◽

Electronic Ground ◽

C Nmr

The paramagnetic 1H nmr spectra for manganocene (1) and 1.1′-dimethylmanganocene (2), and the 13C nmr spectra for 1,1′-diethylmanganocene (3) have been recorded in toluene solvent over a −90 to 90 °C temperature range. 1 shows a low field and a high field ring proton resonance in its spectrum near −59 °C. At higher temperatures the low field resonance is prevalent and becomes gradually averaged due to a fast spin exchange process that dominates the spectrum at 90 °C. For the ring substituted derivatives 2 and 3, resonances due to only one paramagnetic species were detected in the low temperature range. Above ambient temperature a new spectrum due to rapid spin exchange averaging is observed for these complexes. Results are readily interpreted in terms of ground state molecular cross-over exchanges between the 2E2g, 6A1g, and 2A1g spin states of the complexes.

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