scholarly journals Dihydroisoindolo[2,1-a]quinazoline-5,11-dione derivatives as potent and selective inhibitors targeting hepatitis B virus

2015 ◽  
Vol 10 (3) ◽  
pp. 612
Author(s):  
Jun-Fei Zhang ◽  
Bo Liu ◽  
Cong-Xin Chen
Keyword(s):  
Sulfuric Acid ◽  
Mass Spectrum ◽  
Hbv Dna ◽  
Isatoic Anhydride ◽  
Silica Sulfuric Acid ◽  
H Nmr ◽  
Viral Antigens ◽  
Potent Inhibition ◽  
B Virus ◽  
C Nmr

<p>The construction of dihydroisoindolo[2,1-a]quinazoline-5,11-dione derivatives (4a–4m), by  the condensation isatoic anhydride, appropriate amines and 2-formylbenzoic acid by using silica sulfuric acid as catalyst was reported. These dihydroisoindolo[2,1-a]quinazoline-5,11-dione derivatives (DIQ) were identified as potent inhibitors of HBV capsid assembly. The newly synthesized dihydroisoindolo[2,1-a]quinazoline-5,11-dione derivatives 4a-4m were characterized by <sup>1</sup>H NMR, <sup>13</sup>C NMR, and Mass spectrum and evaluated for their anti-HBV activity. Majority of the synthesized compounds inhibited the expression of viral antigens at low concentration. But five compounds, 4a, 4b, 4c, 4f, and 4m were shown potent inhibition of HBV DNA replication at submicromolar range. Of these compounds, compound 4a was the most active when compared with lamivudine.</p><p> </p><p> </p>

scholarly journals Design and synthesis of a novel 5-(aminomethylene)thiazolidine-2,4-dione derivatives as potent hepatitis-B virus polymerase inhibitors

2015 ◽  
Vol 10 (2) ◽  
pp. 271
Author(s):  
Wei-Guo Li ◽  
He-Qun Wang
Keyword(s):  
Hbv Dna ◽  
Biologically Active ◽  
Secondary Amines ◽  
Design And Synthesis ◽  
H Nmr ◽  
Viral Antigens ◽  
Polymerase Inhibitors ◽  
Potent Inhibition ◽  
B Virus ◽  
C Nmr

<p>A series of novel thiazolidinedione analogues (TZD) were designed and synthesized potent inhibitors of HBV capsid assembly. The synthesis of thiazolidine-2,4-dione derivatives (4a–4o), starting from the condensation of 5-(ethoxymethylene)thiazolidine-2,4-dione (1) with various secondary amines (3) derived from biologically active compounds. The newly synthesized TZD analogues 4a-4o were characterized by <sup>1</sup>H NMR, <sup>13</sup>C NMR, and MS and evaluated for their anti-HBV activity. Most of the compounds inhibited the expression of viral antigens at low concentration. Six compounds, 4g, 4h, 4l, 4m, 4n, and 4o, demonstrated potent inhibition of HBV DNA replication at submicromolar range. Of these five initial hits, compound 4o was the most active when compared with lamivudine.</p><p> </p><p> </p>

A 13C nuclear magnetic resonance study of aliphatic ketone protonation in sulfuric acid solutions

1976 ◽  
Vol 54 (5) ◽  
pp. 718-725 ◽  
Author(s):  
Robert A. McClelland ◽  
William F. Reynolds
Keyword(s):  
Sulfuric Acid ◽  
Molecular Size ◽  
Nuclear Magnetic Resonance Study ◽  
Suitable Alternative ◽  
Acidic Solutions ◽  
H Nmr ◽  
Organic Bases ◽  
13C Nuclear Magnetic Resonance ◽  
Sulfuric Acid Solutions ◽  
C Nmr

A 13C nmr investigation of the protonation in sulfuric acid of the aliphatic ketones MeCOR (R = Me, Et, i-Pr, tert-Bu), 3-pentanone, and the cyclic ketones from cyclobutanone through cyclooctanone is reported. With the exception of cyclobutanone which is considerably less basic, these ketones are all very similar in their basicity, with half-protonation in the region 73–78% H2SO4. The acidity dependence of the protonation is discussed; there appears to be a small dependence on molecular size. 13C nmr is shown to be a suitable alternative to 1H nmr in the study of the protonation of weak organic bases in strongly acidic solutions.

Investigation of the reactivity of 4-amino-5-hydrazineyl-4H-1,2, 4-triazole-3-thiol towards some selected carbonyl compounds: synthesis of novel triazolotriazine-, triazolotetrazine-, and triazolopthalazine derivatives

2019 ◽  
Vol 74 (11-12) ◽  
pp. 847-855
Author(s):  
Kamal M. El-Shaieb ◽  
Asmaa H. Mohamed ◽  
Fathy F. Abdel-latif
Keyword(s):  
Mass Spectrometry ◽  
Elemental Analysis ◽  
Carbonyl Compounds ◽  
Spectroscopic Data ◽  
Pyromellitic Dianhydride ◽  
Isatoic Anhydride ◽  
Naphthalic Anhydride ◽  
H Nmr ◽  
Reaction Proceeds ◽  
C Nmr

AbstractThe reactivity of 4-amino-5-hydrazineyl-4H-1,2,4-triazole-3-thiol (1) towards several carbonyl compounds was investigated. We have found that on treatment of 1 with isatoic anhydride (2), 1,8-naphthalic anhydride (4), diphenic anhydride (6), pyromellitic dianhydride (8), and tetrabromophthalic anhydride (10), the reaction proceeds to give triazolotetrazine- and triazolophthalazine derivatives in good yields using simple experimental procedures. The structure of the synthesized compounds was confirmed using different spectroscopic data (1H NMR, 13C NMR, mass spectrometry, and elemental analysis). The mechanism of the obtained products was also discussed.

scholarly journals SINTESIS XANTON DARI ASAM 2-PHENOXYBENZOIC ACID SEBAGAI BAHAN DASAR OBAT MALARIA BARU

2013 ◽  
Vol 15 (2) ◽  
pp. 25-34
Author(s):  
Amanatie Amanatie ◽  
Jumina Jumina ◽  
Mustofa Mustofa ◽  
M. Hanafi
Keyword(s):  
Sulfuric Acid ◽  
Acid Synthesis ◽  
Raw Material ◽  
H Nmr ◽  
Ft Ir ◽  
Acid Catalyzed ◽  
C Nmr

Synthesis of xanthone was conducted from the raw material of 2-phenoxybenzoic acid through acid-catalyzed-cyclization. The product was characterized using UV- Vis, 1 13 d FT-IR, H-NMR, C-NMR, an LC-MS Cyclization of 2-phenoxybenzoic acid using sulfuric acid catalyt gave xanthone in 86.11 % yield. These compounds as the basis of new malaria drugs.Keywords 2-phenoxybenzoic acid, Synthesis, Xanthone, Characterized.

A STUDY OF HEPATITIS B VIRUS GENOTYPES IN CHRONIC HEPATITIS B PATIENTS

2011 ◽  
pp. 25-29
Author(s):  
Keyword(s):  
Chronic Hepatitis ◽  
Hepatitis B ◽  
Chronic Hepatitis B ◽  
Clinical Laboratory ◽  
Laboratory Data ◽  
Hbv Dna ◽  
Hbv Genotypes ◽  
B Virus ◽  
Virus Genotypes ◽  
Genotype C

Aims: To measure the prevalence of HBV genotypes in chronic hepatitis B patients and their relation to HBeAg and HBV DNA level. Methods: 81 patients were enrolled in this study from January 2009 to December 2010. Clinical, laboratory data were collected during the patient’s hospitalization. Sera were quantitatively tested for HBeAg and HBV DNA. HBV genotyping was made by real-time PCR. Results: Among the 81 patients, 60.5% had genotype B, 26.7% had genotype C and 8.6% had mixed genotype B-C. Prevalence of symptoms (fatigue, anorexia, insomnia...) was higher in genotype C than in genotype B. Genotype C patients had positivity higher HBeAg than genotype B patients (56% vs. 38,8%, p <0.05). The rate of HBV DNA > 107 copies/mL was higher in genotype C group than in genotype B group (36% vs. 28,6%, p > 0.05). Conclusions: Most of the patients had genotypes B or C. Patients with genotype C had positive HBeAg and may be related to higher serological HBV DNA level than in genotype B.

Conformational structure of ethylene glycol dibenzoate. Vibrational and NMR spectra

1981 ◽  
Vol 46 (8) ◽  
pp. 1913-1929 ◽  
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.

Synthesis of 2-amino-5,7-dimethyl-4-oxopyrido[3,4-e]-1,3-thiazines

1983 ◽  
Vol 48 (12) ◽  
pp. 3426-3432 ◽  
Author(s):  
Dušan Koščík ◽  
Pavol Kristian ◽  
Ondrej Forgáč
Keyword(s):  
Spectral Data ◽  
Chlorine Atom ◽  
Mass Spectra ◽  
High Reactivity ◽  
Secondary Amines ◽  
Dimroth Rearrangement ◽  
H Nmr ◽  
New Synthesis ◽  
C Nmr

New synthesis of pyrido[3,4-e]-1,3-thiazines consisting in reaction of 2,6-dimethyl-4-chloronicotinoyl isothiocyanate with primary or secondary amines, or with benzaldehyde phenylhydrazone, is described. High reactivity of the chlorine atom does not allow isolation of the corresponding thioureas, arising as intermediates, except in the case of the benzylamino derivative. Structure of the products was unequivocally confirmed by their spectral data (IR, UV, 1H NMR, 13C NMR and mass spectra). The synthesized derivatives do not undergo the Dimroth rearrangement.

Oxynemorensine, an alkaloid from Senecio nemorensis L., var. subdecurrens GRISEB

1980 ◽  
Vol 45 (2) ◽  
pp. 548-558 ◽  
Author(s):  
Antonín Klásek ◽  
Petr Sedmera ◽  
Jindřich Vokoun ◽  
Anna Boeva ◽  
Svatava Dvoráčková ◽  
...  
Keyword(s):  
Unsaturated Acid ◽  
Mass Spectra ◽  
H Nmr ◽  
C Nmr

From S. nemorensis L., var. subdecurrens GRISEB. there were isolated the previously obtained alkaloids nemorensine (I), retroisosenine (II), bulgarsenine (III) and, in addition, the alkaloid oxynemorensine which was assigned the structure VIII on the basis of the interpretation of the 1H-NMR, 13C-NMR, mass spectra, and on that of the identification of the products of hydrolysis and reduction. Furthermore, the isolation of the cis-nemorensic acid (V) as well as that of the unsaturated acid IV, and the transformation of bulgarsenine (III) to nemorensine (I) were described.

21,22-Disubstituted 18α,19βH-Ursane Derivatives with Oxabicyclooctane System in Ring E

1993 ◽  
Vol 58 (1) ◽  
pp. 173-190 ◽  
Author(s):  
Eva Klinotová ◽  
Jiří Klinot ◽  
Václav Křeček ◽  
Miloš Buděšínský ◽  
Bohumil Máca
Keyword(s):  
Spectral Data ◽  
Spin Systems ◽  
Coupling Constants ◽  
Complete Analysis ◽  
Nmr Spectrum ◽  
Proton Proton ◽  
H Nmr ◽  
Proton Coupling ◽  
C Nmr

Reaction of 3β-acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) and 20β,28-epoxy-21,22-dioxo-19α,19βH-ursan-3β-yl acetate (IIIb) with diazomethane afforded derivatives XII-XIV with spiroepoxide group in position 21 or 22, which were further converted into hydroxy derivatives XV and XVII. Ethylene ketals VIII-X were also prepared. In connection with the determination of position and configuration of the functional groups at C(21) and C(22), the 1H and 13C NMR spectral data of the prepared compounds are discussed. Complete analysis of two four-spin systems in the 1H NMR spectrum of bisethylenedioxy derivative Xb led to the proton-proton coupling constants from which the structure with two 1,4-dioxane rings condensed with ring E, and their conformation, was derived.

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

2006 ◽  
Vol 71 (10) ◽  
pp. 1470-1483 ◽  
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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