Tag: 100-200

On August 31, 1999, Al Mamun, Abu Amar M.; Rahman, M. Sayeedur; Humayun, M. Zafri published an article.Application In Synthesis of Imidazo[1,2-c]pyrimidin-5(6H)-one The title of the article was Escherichia coli cells bearing mutA, a mutant glyV tRNA gene, express a recA-dependent error-prone DNA replication activity. And the article contained the following:

A base substitution mutation (mutA) in the Escherichia coli glyV tRNA gene potentiates asp → gly mistranslation and confers a strong mutator phenotype that is SOS independent, but requires recA, recB and recC genes. Here, we demonstrate that mutA cells express an error-prone DNA polymerase by using an in vitro exptl. system based on the conversion of phage M13 single-stranded viral DNA bearing a model mutagenic lesion to the double-stranded replicative form. Amplification of the newly synthesized strand followed by multiplex DNA sequence anal. revealed that mutation fixation at 3,N4-ethenocytosine (εC) was ≈3% when the DNA was replicated by normal cell extracts, ≈48% when replicated by mutA cell extracts and ≈3% when replicated by mutA recA double mutant cell extracts, in complete agreement with previous in vivo results. Mutagenesis at undamaged DNA sites was significantly elevated by mutA cell-free extracts in the M13 lacZ(α) forward mutagenesis system. Neither polA (DNA polymerase I) nor polB (DNA polymerase II) genes are required for the mutA phenotype, suggesting that the phenotype is mediated through a modification of DNA polymerase III or the activation of a previously unidentified DNA polymerase. These findings define the major features of a novel mutagenic pathway and imply the existence of previously unrecognized links between translation, recombination and replication. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).Application In Synthesis of Imidazo[1,2-c]pyrimidin-5(6H)-one

The Article related to trna mutation reca dependent dna replication error escherichia, Biochemical Genetics: Genomic Processes and other aspects.Application In Synthesis of Imidazo[1,2-c]pyrimidin-5(6H)-one

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Barrio, Jorge R.; Sattsangi, Prem D.; Gruber, Bruce A.; Dammann, Laurence G.; Leonard, Nelson J. published an article in 1976, the title of the article was Species responsible for the fluorescence of 3,N4-ethenocytidine.Recommanded Product: 55662-66-3 And the article contains the following content:

The fluorescence properties of 3,N4-ethenocytidine (ε-cytidine) (I), substituted derivatives, and closely related 2-ring heterocycles were examined The chloroacetaldehyde-modified cytidine is fluorescent only in its protonated form. The fluorescence emission maximum is 340 nm and the pKa* is 4.0, very close to the value for the ground state. N-1-alkylation of I at the same position as protonation makes reversion to the nonfluorescent type of structure impossible, on changing the pH, and accordingly the fluorescence emission characteristics are preserved over a wide range of pH. The presence of the n→π* transition of the carbonyl group in I is responsible for the lack of fluorescence in neutral solution Even I.HCl has a low fluorescence quantum yield (Φ < 0.01) and a short fluorescence lifetime (τ = 30 psec). Ring substitution produces a red shift of the π → π* transition, due to inductive or mesomeric effects and a clear improvement in the fluorescence emission characteristics; e.g., 2-acetylamino-5,6-dihydro-5-oxo-6-β-D-ribofuranosylimidazo[1,2-c]pyrimidine, in its protonated form, shows Φ = 0.85 and τ = 4 ns. Imidazo[1,2-a]pyridine, a close model for I lacking the carbonyl group and accordingly the n → π* transition, has a high fluorescence quantum yield and long lifetime in either neutral solution or organic solvents. Both N-1-protonated and -alkylated imidazo[1,2-a]pyridines have emission maxima similar to those observed for I.HCl but higher quantum yields. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).Recommanded Product: 55662-66-3

The Article related to fluorescence etherocytidine, cytidine etheno fluorescence, Carbohydrates: Nucleosides, Nucleotides and other aspects.Recommanded Product: 55662-66-3

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On December 2, 2004, Jurado, Juan; Maciejewska, Agnieszka; Krwawicz, Joanna; Laval, Jacques; Saparbaev, Murat K. published an article.Safety of Imidazo[1,2-c]pyrimidin-5(6H)-one The title of the article was Role of mismatch-specific uracil-DNA glycosylase in repair of 3,N4-ethenocytosine in vivo. And the article contained the following:

The 3,N4-ethenocytosine (εC) residue might have biol. role in vivo since it is recognized and efficiently excised in vitro by the E. coli mismatch-specific uracil-DNA glycosylase (MUG) and the human thymine-DNA glycosylase (hTDG). In the present work we have generated mug defective mutant of E. coli by insertion of a kanamycin cassette to assess the role of MUG in vivo. We show that human TDG complements the enzymic activity of MUG when expressed in a mug mutant. The εC-DNA glycosylase defective strain did not exhibit spontaneous mutator phenotype and did not show unusual sensitivity to any of the following DNA damaging treatments: methylmethanesulfonate, N-methyl-N’-nitro-N-nitrosoguanidine, UV light, H2O2, paraquat. However, plasmid DNA damaged by 2-chloroacetaldehyde treatment in vitro was inactivated at a greater rate in a mug mutant than in wild-type host, suggesting that MUG is required for the in vivo processing of the ethenobases. In addition, 2-chloroacetaldehyde treatment induces preferentially G·C → C·G and A·T → T·A transversions in mug mutant. Comparison of the mutation frequencies induced by the site-specifically incorporated εC residue in E. coli wild-type vs. mug indicates that MUG repairs more than 80% of εC residues in vivo. Furthermore, the results show that nucleotide excision repair and recombination are not involved in the processing of εC in E. coli. Based on the mutagenesis data we suggest that εC may be less toxic and less mutagenic than expected. The increased spontaneous mutation rate for G·C → A·T transition in the ung mug double mutant as compared to the single ung mutant suggest that MUG may be a back-up repair enzyme to the classic uracil-DNA glycosylase. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).Safety of Imidazo[1,2-c]pyrimidin-5(6H)-one

The Article related to uracil dna glycosylase repair ethenocytosine escherichia, Biochemical Genetics: Genomic Processes and other aspects.Safety of Imidazo[1,2-c]pyrimidin-5(6H)-one

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On March 31, 1999, Rahman, M. Sayeedur; Humayun, M. Zafri published an article.Formula: C6H5N3O The title of the article was SOS and UVM pathways have lesion-specific additive and competing effects on mutation fixation at replication-blocking DNA lesions. And the article contained the following:

Escherichia coli cells have multiple mutagenic pathways that are induced in response to environmental and physiol. stimuli. Unlike the well-investigated classical SOS response, little is known about newly recognized pathways such as the UVM (UV modulation of mutagenesis) response. In this study, we compared the contributions of the SOS and UVM pathways on mutation fixation at two representative noninstructive DNA lesions: 3,N4-ethenocytosine (εC) and abasic (AP) sites. Because both SOS and UVM responses are induced by DNA damage, and defined UVM-defective E. coli strains are not yet available, we first constructed strains in which expression of the SOS mutagenesis proteins UmuD’ and UmuC (and also RecA in some cases) is uncoupled from DNA damage by being placed under the control of a heterologous lac-derived promoter. M13 single-stranded viral DNA bearing site-specific lesions was transfected into cells induced for the SOS or UVM pathway. Survival effects were determined from transfection efficiency, and mutation fixation at the lesion was analyzed by a quant. multiplex sequence anal. procedure. Our results suggest that induction of the SOS pathway can independently elevate mutagenesis at both lesions, whereas the UVM pathway significantly elevates mutagenesis at εC in an SOS-independent fashion and at AP sites in an SOS-dependent fashion. Although mutagenesis at εC appears to be elevated by the induction of either the SOS or the UVM pathway, the mutational specificity profiles for εC under SOS and UVM pathways are distinct. Interestingly, when both pathways are active, the UVM effect appears to predominate over the SOS effect on mutagenesis at εC, but the total mutation frequency is significantly increased over that observed when each pathway is individually induced. These observations suggest that the UVM response affects mutagenesis not only at class 2 noninstructive lesions (εC) but also at classical SOS-dependent (class 1) lesions such as AP sites. Our results add new layers of complexity to inducible mutagenic phenomena: DNA damage activates multiple pathways that have lesion-specific additive as well as suppressive effects on mutation fixation, and some of these pathways are not directly regulated by the SOS genetic network. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).Formula: C6H5N3O

The Article related to sos uvm response dna repair mutagenesis, Biochemical Genetics: Genomic Processes and other aspects.Formula: C6H5N3O

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Li, Deyu; Delaney, James C.; Page, Charlotte M.; Chen, Alvin S.; Wong, Cintyu; Drennan, Catherine L.; Essigmann, John M. published an article in 2010, the title of the article was Repair of DNA alkylation damage by the Escherichia coli adaptive response protein AlkB as studied by ESI-TOF mass spectrometry.HPLC of Formula: 55662-66-3 And the article contains the following content:

DNA alkylation can cause mutations, epigenetic changes, and even cell death. All living organisms have evolved enzymic and non-enzymic strategies for repairing such alkylation damage. AlkB, one of the Escherichia coli adaptive response proteins, uses an α-ketoglutarate/Fe(II)-dependent mechanism that, by chem. oxidation, removes a variety of alkyl lesions from DNA, thus affording protection of the genome against alkylation. In an effort to understand the range of acceptable substrates for AlkB, the enzyme was incubated with chem. synthesized oligonucleotides containing alkyl lesions, and the reaction products were analyzed by electrospray ionization time-of-flight (ESI-TOF) mass spectrometry. Consistent with the literature, but studied comparatively here for the first time, it was found that 1-methyladenine, 1,N6-ethenoadenine, 3-methylcytosine, and 3-ethylcytosine were completely transformed by AlkB, while 1-methylguanine and 3-methylthymine were partially repaired. The repair intermediates (epoxide and possibly glycol) of 3,N4-ethenocytosine are reported for the first time. It is also demonstrated that O6-methylguanine and 5-methylcytosine are refractory to AlkB, lending support to the hypothesis that AlkB repairs only alkyl lesions attached to the nitrogen atoms of the nucleobase. ESI-TOF mass spectrometry is shown to be a sensitive and efficient tool for probing the comparative substrate specificities of DNA repair proteins in vitro. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).HPLC of Formula: 55662-66-3

The Article related to dna alkylation repair escherichia alkb, Biochemical Genetics: Genomic Processes and other aspects.HPLC of Formula: 55662-66-3

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Bartholomew, David G.; Dea, Phoebe; Robins, Roland K.; Revankar, Ganapathi R. published an article in 1975, the title of the article was Imidazo[1,2-c]pyrimidine nucleosides. Synthesis of N-bridgehead inosine monophosphate and guanosine monophosphate analogs related to 3-deazapurines.Application In Synthesis of Imidazo[1,2-c]pyrimidin-5(6H)-one And the article contains the following content:

Cyclization of 4-amino-6-chloro-2-pyrimidinol with BrCH2CH(OEt)2 gave 7-chloroimidazo[1,2-c]pyrimidin-5-one (I). Direct glycosylation of the trimethylsilyl derivative of I with 2,3,5-tri-O-acetyl-D-ribofuranosyl bromide in MeCN gave an anomeric mixture of 7-chloro-1-(2,3,5-tri-O-acetyl-D-ribofuranosyl)imidazo[1,2-c]pyrimidin-5-one, which on deacetylation and separation of anomers furnished 7-chloro-1-β-D-ribofuranosylimidazo[1,2-c]pyrimidin-5-one (II) and its α anomer (III). However, the glycosylation of trimethylsilylated I with tetra-O-acetyl-β-D-ribofuranose in dichloroethane containing SnCl4, followed by aminolysis gave only II. Catalytic dehalogenation of II and III gave 1-β-D-ribofuranosylimidazo[1,2-c]pyrimidin-5-one (IV) and its α anomer (V), resp. Amination of II gave 7-amino-1-β-D-ribofuranosylimidazo[1,2-c]pyrimidin-5-one (VI). Phosphorylation of IV, V, and VI gave 1-β-D-ribofuranosylimidazo[1,2-c]pyrimidin-5-one 5′-monophosphate, the IMP analog α anomer and 7-amino-1-β-D-ribofuranosylimidazo[1,2-c]pyrimidin-5-one 5′-monophosphate, resp. The ribosylation site was determined by using 13C NMR and the anomeric configurations were established by using PMR of the 2′,3′-O-isopropylidene derivatives of II and III. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).Application In Synthesis of Imidazo[1,2-c]pyrimidin-5(6H)-one

The Article related to imidazopyrimidine nucleoside analog, Carbohydrates: Nucleosides, Nucleotides and other aspects.Application In Synthesis of Imidazo[1,2-c]pyrimidin-5(6H)-one

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Boulias, Konstantinos; Greer, Eric Lieberman published an article in 2021, the title of the article was Detection of DNA Methylation in Genomic DNA by UHPLC-MS/MS.Formula: C6H7N5 And the article contains the following content:

DNA methylation serves to mark DNA as either a directed epigenetic signaling modification or in response to DNA lesions. Methods for detecting DNA methylation have become increasingly more specific and sensitive over time. Conventional methods for detecting DNA methylation, ranging from paper chromatog. to differential restriction enzyme digestion preference to dot blots, have more recently been supplemented by ultrahigh performance liquid chromatog. coupled with mass spectrometry (UHPLC-MS/MS) to accurately quantify specific DNA methylation. Methylated DNA can also be sequenced by either methylated DNA immunoprecipitation followed by sequencing (MeDIP-seq) or single-mol. real-time sequencing (SMRTseq) for identifying genomic locations of DNA methylation. Here we describe a protocol for the detection and quantification of epigenetic signaling DNA methylation modifications including, N6-methyladenine (6mA), N4-methylcytosine (4mC) and C5-methylcytosine (5mC) in genomic DNA by triple quadrupole liquid chromatog. coupled with tandem mass spectrometry (QQQ-LC-MS/MS). The high sensitivity of the UHPLC-MS/MS methodol. and the use of calibration standards of pure nucleosides allow for the accurate quantification of DNA methylation. The experimental process involved the reaction of N-Methyl-7H-purin-6-amine(cas: 443-72-1).Formula: C6H7N5

The Article related to genomic dna methylation uhplc ms, 4mc, 5mc, 6ma, c5-methylcytosine, n4-methylcytosine, n6-methyladenine, uhplc-ms/ms, methylated dna, Biochemical Methods: Chromatographic and other aspects.Formula: C6H7N5

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Revankar, Ganapathi R.; Matthews, Thomas R.; Robins, Roland K. published an article in 1975, the title of the article was Synthesis and antimicrobial activity of certain imidazo[1,2-a]pyrimidines.Computed Properties of 57473-33-3 And the article contains the following content:

A series of 5-substituted and 5,7-disubstituted imidazo[1,2-a]pyrimidines (I) were prepared and the in vitro antimicrobial activity of these compounds against a variety of microorganisms tested. 5-N-octylaminoimidazo[1,2-a]pyrimidine [57473-44-6] exhibited significant activity against all the microorganisms tested. The experimental process involved the reaction of 7-Chloroimidazo[1,2-a]pyrimidin-5(1H)-one(cas: 57473-33-3).Computed Properties of 57473-33-3

The Article related to bactericide imidazopyrimidine derivative, bactericide methylsulfinyl nitrofuran analog, Pharmacodynamics: Structure-Activity and other aspects.Computed Properties of 57473-33-3

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On January 20, 2021, Si, Zhangyong; Hou, Zheng; Vikhe, Yogesh Shankar; Thappeta, Kishore Reddy Venkata; Marimuthu, Kalisvar; De, Partha Pratim; Ng, Oon Tek; Li, Peng; Zhu, Yabin; Pethe, Kevin; Chan-Park, Mary B. published an article.Synthetic Route of 5036-48-6 The title of the article was Antimicrobial Effect of a Novel Chitosan Derivative and Its Synergistic Effect with Antibiotics. And the article contained the following:

Cationic polymers are promising antibacterial agents because bacteria have a low propensity to develop resistance against them, but they usually have low biocompatibility because of their hydrophobic moieties. Herein, we report a new biodegradable and biocompatible chitosan-derived cationic antibacterial polymer, 2,6-diamino chitosan (2,6-DAC). 2,6-DAC shows excellent broad-spectrum antimicrobial activity with min. inhibitory concentrations (MICs) of 8-32μg/mL against clin. relevant and multidrug-resistant (MDR) bacteria including Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. Furthermore, 2,6-DAC shows an excellent synergistic effect with various clin. relevant antibiotics proved by decreasing the MICs of the antibiotics against MDR A. baumannii and methicillin-resistant Staphylococcus aureus to <1μg/mL. In vivo biocompatibility of 2,6-DAC is proved by a dosage of 100 mg/kg compound via oral administration and 25 mg/kg compound via i.p. injection to mice; 2,6-DAC does not cause any weight loss and any significant change in liver and kidney biomarkers or the important blood electrolytes. The combinations of 2,6-DAC together with novobiocin and rifampicin show >2.4 log10 reduction of A. baumannii in murine i.p. and lung infection models. The novel chitosan derivative, 2,6-DAC, can be utilized as a biocompatible broad-spectrum cationic antimicrobial agent alone or in synergistic combination with various antibiotics. The experimental process involved the reaction of N-(3-Aminopropyl)-imidazole(cas: 5036-48-6).Synthetic Route of 5036-48-6

The Article related to antimicrobial chitosan derivative synergistic antibiotic, antibacterial, biocompatible, chitosan derivatives, nanoparticle, synergistic effect with antibiotics, Industrial Carbohydrates: Nonsugars and other aspects.Synthetic Route of 5036-48-6

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On February 28, 1991, Debnath, Asim Kumar; Lopez de Compadre, Rosa L.; Debnath, Gargi; Shusterman, Alan J.; Hansch, Corwin published an article.Product Details of 5709-67-1 The title of the article was Structure-activity relationship of mutagenic aromatic and heteroaromatic nitro compounds. Correlation with molecular orbital energies and hydrophobicity. And the article contained the following:

A survey of the literature yielded data on over 200 aromatic and heteroaromatic nitro compounds tested for mutagenicity in the Ames test using S. typhimurium TA98. From the data, a QSAR has been derived for 188 congeners. The main determinants of mutagenicity are the hydrophobicity (modeled by octanol/water partition coefficients) and the energies of the lowest unoccupied mol. orbitals calculated using the AM1 method. It is also shown that chems. possessing three or more fused rings possess much greater mutagenic potency than compounds with one or two fused rings. Since the QSAR is based on a very wide range in structural variation (aromatic rings from benzene to coronene are included as well as many different types of heterocycles), it is a significant step toward a predictive toxicol., with value in the design of less mutagenic bioactive compounds The experimental process involved the reaction of 2-Nitro-1H-benzo[d]imidazole(cas: 5709-67-1).Product Details of 5709-67-1

The Article related to mutagenicity qsar aromatic heteroaromatic nitro compound, hydrophobicity nitro compound mutagenicity, lumo nitro compound mutagenicity, Physical Organic Chemistry: General and other aspects.Product Details of 5709-67-1

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem