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Amino Derivatives (amino + derivative)
Selected AbstractsMechanism of H-8 inhibition of Cyclin-dependent kinase 9: study using inhibitor-immobilized matricesGENES TO CELLS, Issue 3 2003Daisuke Shima Background: Positive transcription elongation factor b (P-TEFb), which phosphorylates the carboxyl-terminal domain (CTD) of RNA polymerase II (RNAPII), is comprised of the catalytic subunit cyclin-dependent kinase 9 (CDK9) and the regulatory subunit cyclin T. The kinase activity and transcriptional activation potential of P-TEFb is sensitive to various compounds, including H-8, 5,6-dichloro-1-,-d-ribofuranosylbenzimidazole (DRB), and flavopiridol. Results: We investigated the molecular mechanism of the H-8 inhibition of CDK9 using matrices to which H-9, an amino derivative of H-8, was immobilized. CDK9 bound specifically to H-9, and this interaction was competitively inhibited by ATP and DRB, but not by flavopiridol. Mutational analyses demonstrated that the central region of CDK9, which encompasses the T-loop region, was important for its binding to H-9. Conclusions: H-9-immobilized latex beads are useful for trapping CDK9 and a subset of kinases from crude cell extracts. The flavopiridol-binding region of CDK9 is most likely different from its H-9-binding region. These biochemical data support previously reported observations which were based on crystallographic data. [source] Synthesis and reactions of 3-amino-2-methyl-3H -[1,2,4]triazolo[5,1- b]-quinazolin-9-one and 2-hydrazino-3-phenylamino-3H -quinazolin-4-oneJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2003Mohamed A. Saleh The reaction of 3- N -(2-mercapto-4-oxo-4H -quinazolin-3-yl)acetamide (1) with hydrazine hydrate yielded 3-amino-2-methyl-3H -[1,2,4]triazolo[5,1- b]quinazolin-9-one (2). The reaction of 2 with o -chlorobenzaldehyde and 2-hydroxy-naphthaldehyde gave the corresponding 3-arylidene amino derivatives 3 and 4, respectively. Condensation of 2 with 1-nitroso-2-naphthol afforded the corresponding 3-(2-hydroxy-naphthalen-1-yl-diazenyl)-2-methyl-3H -[1,2,4]triazolo[5,1- b]quinazolin-9-one (5), which on subsequent reduction by SnCl2 and HCl gave the hydrazino derivative 6. Reaction of 2 with phenyl isothiocyanate in refluxing ethanol yielded thiourea derivative 7. Ring closure of 7 subsequently cyclized on refluxing with phencyl bromide, oxalyl dichloride and chloroacetic acid afforded the corresponding thiazolidine derivatives 8, 9 and 10, respectively. Reaction of 2-mercapto-3-phenylamino-3H -quinazolin-4-one (11) with hydrazine hydrate afforded 2-hydrazino-3-phenylamino-3H -quinazolin-4-one (12). The reactivity 12 towards carbon disulphide, acetyl acetone and ethyl acetoacetate gave 13, 14 and 15, respectively. Condensation of 12 with isatin afforded 2-[N -(2-oxo-1,2-dihydroindol-3-ylidene)hydrazino]-3-phenylamino-3H -quinazolin-4-one (16). 2-(4-Oxo-3-phenylamino-3,4-dihydroquinazolin-2-ylamino)isoindole-1,3-dione (17) was synthesized by the reaction of 12 with phthalic anhydride. All isolated products were confirmed by their ir, 1H nmr, 13C nmr and mass spectra. [source] High quantum yield photoluminescence of new polyamides containing oligo-PPV amino derivatives and related oligomersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2009Antonio Roviello Abstract The synthesis and the chemical physical characterization of new photoluminescent (PL) chromophores and polymers are reported. Chromophores (oligo-PPV symmetric derivatives ending with amino groups) are strong blue emitters with a PL quantum yield of ,70% in dioxane solution. They have been used to prepare polyamides by reaction with aliphatic acyl dichlorides in which emitting and non emitting units are alternated. PL properties of the synthesized polyamides have been evaluated in solution and reveal a strong blue emission (PL quantum yield ,60%), To increase the solubility of these systems, oligomers have been purposely prepared and then characterized. They show a peculiar white emission when excited in DMF solution; to get insight into this interesting behavior, asymmetric monoacetylated chromophores have been prepared as model compounds for the chromophoric end groups of the polyamide chains. The emission spectra of these compounds reveal a broad excimeric yellow emission which is responsible, along with the blue emission of the inner chromophoric units, of the overall white emission of the oligomers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2677,2689, 2009 [source] Evaluation of mutagenic and antimutagenic properties of some bioactive xanthone derivatives using Vibrio harveyi testLETTERS IN APPLIED MICROBIOLOGY, Issue 3 2010Abstract Aims:, Drug safety evaluation plays an important role in the early phase of drug development, especially in the preclinical identification of compounds' biological activity. The Vibrio harveyi assay was used to assess mutagenic and antimutagenic activity of some aminoalkanolic derivatives of xanthone (1,5), which were synthesized and evaluated for their anticonvulsant and hemodynamic activities. Methods and Results:, A novel V. harveyi assay was used to assess mutagenic and antimutagenic activity of derivatives of xanthone 1,5. Two V. harveyi strains were used: BB7 (natural isolate) and BB7M (BB7 derivative containing mucA and mucB genes on a plasmid pAB91273, products of these genes enhance error-prone DNA repair). According to the results obtained, the most beneficial mutagenic and antimutagenic profiles were observed for compounds 2 and 3. A modification of the chemical structure of compound 2 by the replacement of the hydroxy group by a chloride improved considerably the antimutagenic activity of the compound. Thus, antimutagenic potency reached a maximum with the presence of tertiary amine and chloride atom in the side chain. Conclusions:, Among the newly synthesized aminoalkanolic derivatives of xanthone with potential anticonvulsant properties, there are some compounds exhibiting in vitro antimutagenic activity. In addition, it appears that the V. harveyi assay can be applied for primary mutagenicity and antimutagenicity assessment of compounds. Significance and Impact of the Study:, The obtained preliminary mutagenicity and antimutagenicity results encourage further search in the group of amino derivatives of xanthone as the potential antiepileptic drugs also presenting some antimutagenic potential. Furthermore, V. harveyi test may be a useful tool for compounds safety evaluation. [source] Enhanced post-source decay and cross-ring fragmentation of oligosaccharides facilitated by conversion to amino derivativesRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 13 2004Jan Muzikar Post-source decay (PSD) fragmentation of chemically or enzymatically produced aminoglycans has been evaluated through matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Conversion of native glycans to their respective aminoglycan derivatives improved detection sensitivity of the usual fragments and promoted cross-ring fragmentation of linear oligosaccharides, facilitating linkage recognition. The cross-ring fragmentations for both dextrin and dextran oligosaccharides were not limited to the reducing-end glucose moiety, as they were extended throughout the entire molecule. When the amino group was generated for N-glycans derived from three different glycoproteins, an enhancement of PSD was observed, without a significant extent of cross-ring fragmentation. Copyright © 2004 John Wiley & Sons, Ltd. [source] | |||||||||||||