The synthesis of the isomeric N-methyl derivatives of murexine

1981 ◽  
Vol 34 (8) ◽  
pp. 1739 ◽  
Author(s):  
CC Duke ◽  
JV Eichholzer ◽  
JK Macleod
Keyword(s):  
Imidazole Ring ◽  
The Other ◽  
Pharmacological Activities ◽  
Tautomeric Forms ◽  
Methyl Derivatives ◽  
Paramagnetic Ions ◽  
Nucella Emarginata ◽  
Derivatives Of

The two isomeric N-methyl derivatives of murexine have been synthesised by independent routes and shown to be different from an 'N- methylmurexine' reportedly isolated from the mollusc Nucella emarginata. 1H n.m.r. studies have shown a marked difference in the extent of binding to paramagnetic ions of the two N-methyl derivatives of murexine in water while pharmacological results show substantially different pharmacological activities of the two isomers. Both results can be rationalized in terms of the observed activities being associated with the presence of one or the other of the tautomeric forms of the imidazole ring.

scholarly journals Genetic variation between mice in their metabolism of coumarin and its derivatives

1978 ◽  
Vol 31 (2) ◽  
pp. 177-186 ◽  
Author(s):  
I. E. Lush ◽  
Kathryn M. Andrews
Keyword(s):  
The Other ◽  
Chromosome 7 ◽  
High Group ◽  
Substrate Specificities ◽  
Adult Females ◽  
Methyl Derivatives ◽  
The Difference ◽  
Cytochrome P 450 ◽  
Derivatives Of ◽  
Medium Group

SUMMARYAdult females from 19 strains of mice were injected with either coumarin or 7-ethoxycoumarin and the urinary excretion of the umbelliferone produced by the metabolism of these substances was measured. With the exception of C57L the strains fell into three classes as follows: high metabolizers (DBA/1 and DBA/2), medium metabolizers (CBA, 129/Rr, NZB and NZW) and low metabolizers (the other 12 strains). The difference in metabolizing ability between the medium group and the low group of strains was also evident when the 4-methyl derivatives of the same two substances were used. However with the 4-methyl derivatives there was no difference in metabolizing ability between the medium group and the high group. The results are interpreted as evidence that the gene Coh on chromosome 7 comprises two closely linked genes which determine cytochrome P-450 isozymes with different substrate specificities.

Production of phenylacetic acid by Bacteroides melaninogenicus ssp. intermedius serogroup C-1

1983 ◽  
Vol 29 (2) ◽  
pp. 276-279
Author(s):  
Kaethe P. Ferguson ◽  
William R. Mayberry ◽  
Dwight W. Lambe Jr.
Keyword(s):  
Gas Chromatography ◽  
Acid Production ◽  
Phenylacetic Acid ◽  
The Other ◽  
Species Status ◽  
Data Support ◽  
Methyl Derivatives ◽  
Bacteroides Gingivalis ◽  
Derivatives Of

The methyl derivatives of broth cultures of black-pigmented Bacteroides were examined by gas chromatography for production of phenylacetic acid. Two serogroups of B. melaninogenicus ssp. intermedius described by Lambe differed in the ability to produce phenylacetate. Serogroup C failed to produce phenylacetic acid while serogroup C-1 produced small amounts of phenylacetate, which contributed 2.2–5.7% to the total nonvolatile acid profile. Holdeman's newly proposed species "B. intermedius" and "B. corporis" correspond to serogroups C and C-1, respectively. These data support the elevation of the two serogroups of B. melaninogenicus ssp. intermedius to species status. Bacteroides gingivalis produced phenylacetate in significantly larger quantities than B. corporis. Bacteroides melaninogenicus ssp. melaninogenicus, "B. melaninogenicus ssp. levii," and B. asaccharolyticus did not produce phenylacetic acid. These results indicate that phenylacetic acid production may be useful in distinguishing "B. corporis" and B. gingivalis from the other black-pigmented Bacteroides.

THE TAUTOMERISM OF 2-NITRAMINOPYRIDINES

1953 ◽  
Vol 31 (11) ◽  
pp. 1048-1053 ◽  
Author(s):  
Alfred Taurins ◽  
Silvio J. Viron
Keyword(s):  
Resonance Structures ◽  
Tautomeric Forms ◽  
Methyl Derivatives ◽  
Derivatives Of

The nitration of 2-amino-4,6-dimethylpyridine with a mixture of nitric and sulphuric acids gives 4,6-dimethyl-2-nitramino-5-nitropyridine (III). 2-Nitraminopyridine (I), 4-methyl-2-nitraminopyridine (II), and (III) produce with diazomethane methyl derivatives of their tautomeric nitramino and nitrimino forms. Diazoethane gives with (I) both the expected ethyl derivatives. However, from (II) only the ethyl derivative of the nitramino form has been obtained. Diazopropane produces with (I) or (II) the propyl derivatives of the nitramino forms only. The resonance structures of the two tautomeric forms of 2-nitraminopyridine have been advanced.

scholarly journals Electrostatic effects on disproportionation equilibria: dihalogeno and methyl derivatives of benzene

1984 ◽  
Vol 62 (11) ◽  
pp. 2337-2339 ◽  
Author(s):  
Zdeněk Friedl
Keyword(s):  
Gas Phase ◽  
The Other ◽  
Transfer Reactions ◽  
Electrostatic Energy ◽  
Benzene Derivatives ◽  
Strong Resonance ◽  
Conformational Equilibria ◽  
Proton Transfer Reactions ◽  
Methyl Derivatives ◽  
Derivatives Of

The disproportionation equilibria of benzene derivatives X—Ph—Y (X, Y = F, Cl, CH3) in the gas phase, were calculated from their enthalpies and entropies of formation at 298 K. Calculations of the electrostatic energy based on the point charges approximation method predict reasonably well the reaction enthalpies of all meta-benzene derivatives and predict nearly as well the other fluoro- and methyl-derivatives. The theory fails if strong resonance and/or steric interactions are present. The generally better ability of the electrostatic theory to treat disproportionation or conformational equilibria than the proton transfer reactions is also discussed.

scholarly journals Synthesis and anticonvulsant activity of some 1-cyclohexylidine/ cycloheptylidine-4-substitued semicarbazide derivatives

2017 ◽  
pp. 51-56
Author(s):  
Alok Jain ◽  
Shailendra Patil ◽  
Asmita Gajbhiye
Keyword(s):  
Molecular Weight ◽  
Acetic Acid ◽  
Anticonvulsant Activity ◽  
Sodium Acetate ◽  
Hind Limb ◽  
Glacial Acetic Acid ◽  
The Other ◽  
Methyl Derivatives ◽  
Derivatives Of ◽  
Sodium Cyanate

Aryl semicarbazide derivatives are reported to possess anticonvulsant activity. On the other hand unsubstituted and small substituents (less than 3 carbon atom) containing cyclohexanones prevented both pentylenetetrazole and MES induced seizures. Similarly cycloheptanone fused with benzodiazepine and furan produced anticonvulsant compounds. Therefore looking into the above facts in the present study, we have synthesized 12 derivatives of 1-cyclohexylidine/cycloheptylidine-4-substitued semicarbazide derivatives and screened them for anticonvulsant activity. The synthesis of compounds was achieved as follows: The various para substituted (H, CH3, F,Cl,Br, I) anilines were converted to aryl ureas by reacting with sodium cyanate in the presence of glacial acetic acid. These aryl ureas and aryl semicarbazides were synthesized by allowing them to react with hydrazine hydrate. Finally the aryl semicarbazides were condensed with cyclohexanone/ cycloheptanone in the presence of sodium acetate to give title compounds. All the synthesized compounds were evaluated for anticonvulsant activity by MES method using carbamazepine as standard and it was observed that all the compounds possess anticonvulsant activity comparable to carbamazepine. Carbamazepine had shown the abolition in the hind limb extensor tonic convulsion after 2 sec. whereas few compounds i.e. 1-cyclohexylidine-4-(4-fluorophenyl) semicarbazide, 1-cycloheptylidine-4-(4- fluorophenyl) semi-carbazide and 1-cycloheptylidine-4-phenylsemicarbazide were more active than standard. Overall it was found that cycloheptyl containing compounds were more active than cyclohexyl containing compounds. The unsubstitued compounds were more active than halo derivatives i.e. electron withdrawing groups, and halo compounds were more active than methyl derivatives i.e. electron donating group (CH3). The order of activity for cyclohexanone and cycloheptanone derivatives is as follows: H >F >Cl >Br >I >CH3. Among the halo derivatives, the activity decreased with increasing molecular weight of halo substituents.

343. 1,4-Dimethoxyphthalazine and the other O- and N-methyl derivatives of phthalhydrazide

1960 ◽  
pp. 1710 ◽  
Author(s):  
J. A. Elvidge ◽  
A. P. Redman
Keyword(s):  
The Other ◽  
Methyl Derivatives ◽  
Derivatives Of

Physical Properties of TCNQ Salts with N-Methyl Derivatives of Pyridine

1982 ◽  
Vol 85 (1) ◽  
pp. 257-263 ◽  
Author(s):  
A. Graja ◽  
M. Przybylski ◽  
B. Butka ◽  
R. Swietlik
Keyword(s):  
Physical Properties ◽  
Methyl Derivatives ◽  
Derivatives Of

Energy Approximation

2017 ◽  
Author(s):  
Philip Isett
Keyword(s):  
Main Lemma ◽  
The Other ◽  
Coarse Scale ◽  
Continuous Solutions ◽  
Material Derivative ◽  
Energy Variation ◽  
Energy Approximation ◽  
The Difference ◽  
Derivatives Of

This chapter presents the equations and calculations for energy approximation. It establishes the estimates (261) and (262) of the Main Lemma (10.1) for continuous solutions; these estimates state that we are able to accurately prescribe the energy that the correction adds to the solution, as well as bound the difference between the time derivatives of these two quantities. The chapter also introduces the proposition for prescribing energy, followed by the relevant computations. Each integral contributing to the other term can be estimated. Another proposition for estimating control over the rate of energy variation is given. Finally, the coarse scale material derivative is considered.

Experimental and Theoretical Investigations of Complex Formation of Substituted Phenylazo-Derivatives of Methylphloroglucinol

2016 ◽  
Vol 12 (8) ◽  
pp. 295-300
Author(s):  
Olga Kovalchukova ◽  
Amangdam A.T. ◽  
Strashnova S.B. ◽  
Strashnov P.V. ◽  
Romashkina E.P. ◽  
...  
Keyword(s):  
Complex Formation ◽  
Organic Ligand ◽  
Spectrophotometric Titration ◽  
Organic Ligands ◽  
Oh Groups ◽  
Tautomeric Forms ◽  
Theoretical Investigations ◽  
Derivatives Of ◽  
Theoretical Results ◽  
Titration Technique

Using spectrophotometric titration technique, the processes of complex formation of some phenylazo-derivatives of methylphloroglucinol (MPG) containing hydroxo-, nitro- and nitroso-substituents were studied. The spectral criteria of neutral and ionized forms of the organic ligands in their different tautomeric forms were determined.It was detected that the complex formation is accompanied by formation of one or two chelate cycles which involve azo- or nitroso-fragments and neighboring OH-groups of the organic ligands. Different types of coordination lead to different changes in the electronic absorption spectra.The DFT-B3LYP modeling of a Ni(II) complex of α-hydroxyphenylazo MPG established the most probable coordination mode of the organic ligand: tridentate chelating dianion, distorted square coordination of Ni-cations including one water molecule.  The theoretical results are in a good accordance with the experimental data.

A Comprehensive Review on the Therapeutic Versatility of Imidazo [2,1-b]thiazoles

2020 ◽  
Vol 27 (40) ◽  
pp. 6864-6887 ◽  
Author(s):  
Mohd Adil Shareef ◽  
Irfan Khan ◽  
Bathini Nagendra Babu ◽  
Ahmed Kamal
Keyword(s):  
Literature Review ◽  
Medicinal Chemistry ◽  
Therapeutic Agents ◽  
Present Review ◽  
Thiazole Derivatives ◽  
Pharmacological Activities ◽  
Comprehensive Review ◽  
Derivatives Of

Background:: Imidazo[2,1-b]thiazole, a well-known fused five-membered hetrocycle is one of the most promising and versatile moieties in the area of medicinal chemistry. Derivatives of imidazo[2,1-b]thiazole have been investigated for the development of new derivatives that exhibit diverse pharmacological activities. This fused heterocycle is also a part of a number of therapeutic agents. Objective:: To review the extensive pharmacological activities of imidazo[2,1-b]thiazole derivatives and the new molecules developed between 2000-2018 and their usefulness. Method:: Thorough literature review of all relevant papers and patents was conducted. Conclusion:: The present review, covering a number of aspects, is expected to provide useful insights in the design of imidazo[2,1-b]thiazole-based compounds and would inspire the medicinal chemists for a comprehensive and target-oriented information to achieve a major breakthrough in the development of clinically viable candidates.

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