By comparison, the thiol analog, prepared according to piccirilli and co-workers ( ), was also converted to the triphosphate derivative, but stored with the thiol protected as the disulfide. Additionally, helene and co-workers have simultaneously incorporated two modified deoxynucleotides into a dna transcript ( ). Uv analyses were performed on a beckman du 640 spectrophotometer.
Synthesis and phosphodiesterase 5 inhibitory activity of new 5-phenyl-1,6-dihydro-7h-pyrazoio4,3-dpyrimidin-7-one derivatives containing an n-acylamido group on a phenyl ring synthesis in dry media coupled with microwave irradiation application to the preparation of -aminoesters and -lactams via silyl ketene acetals and aldimines bram, g. Ammonium hydroxide was then removed and the deprotected nucleoside triphosphate was dissolved in water. M solution in dmf) were added and the reaction was allowed to stir for an additional 45 min with cooling.
Sakthivel and barbas synthesized a series of 5-modified dutp analogs which included both cationic and anionic residues as well as ). Ush-containing rna lane 5, reverse transcript from 1 pmol ush-containing rna lane 6, reverse transcript from 2 pmol ush-containing rna. Rnas that each contained 15 (25) unh b shows the digestion analysis of products from an rna 15mer containing only three ush residues.
Filled triangle, utp transcription filled circle, unh transcription filled square, ush transcription. Beckman 114m solvent delivery units were used to obtain a flow rate of 7 mlmin with a gradient of 01 m nacl aqueous solution buffered with 20 mm trishcl (ph 7. Time course of the incorporation of the single modified nucleotide in the 5mer transcript (5-ggucg-3).
Libraries of n-alkylaminoheterocycles from nucleophilic aromatic substitution with purification by solid supported liquid extraction synthesis of diaryl ethers, diaryl thioethers, and diarylamines mediated by potassium fluoridealumina and 18-crown-6 expansion of scope and utility efficient synthesis of n,n-disubstituted 5-aminothiophene-2-carboxaldehydes by nucleophilic aromatic substitution in water nucleophilic reactions in the pyrrole series displacement of halogen as a tool to functionalize the pyrrole nucleus novel ampa receptor antagonists synthesis and structure-activity relationships of 1-hydroxy-7-(1h-imidazol-1-yl)-6-nitro-2,3(1h,4h)- quinoxalinedione and related compounds synthesis of n-substituted n-nitrosohydroxylamines as inhibitors of mushroom tyrosinase heterocyclic studies. Fraction of label incorporated reflects the total isotope available in solution. Rna 15mer transcript 5-ggcguacguacgua-3 in which the u residues are ush.
Under those conditions, transcription efficiency increased to a value of 10 of that observed with utp (data not shown). Ush and to 22 with 5 mm ush, in both cases with 5 mm of the other three common nucleotide triphosphates (fig. Nevertheless, the functional scope of nucleic acids is likely limited since they possess a narrow range of functionality, at least when compared with proteins ( ). The 60mer transcript contained six uridines but no uridines in the reverse transcription primer binding site. The 2d and 3d hydrogen bonding descriptors that help to study qspr were also calculated.
Dna polymerase, snake venom phosphodiesterase and calf intestinal alkaline phosphatase were purchased from boehringer (mannheim, germany). Initial transcription studies were performed using a double-stranded t7 rna polymerase promoter followed by a single-stranded template ( ), which coded for a 5mer and contained one site for analog incorporation (transcript, 5-ggucg-3). Beckman 114m solvent delivery units were used to obtain a flow rate of 7 mlmin with a gradient of 01 m nacl aqueous solution buffered with 20 mm trishcl (ph 7. In both cases control reactions with utp were used. The majority of these studies have focused on the modification and selection of dna, presumably due to its enhanced chemical stability relative to rna, but rna plays a more active role in the cell and might be expected to exhibit a greater catalytic potential than dna.
Nmr spectra were obtained on 400 and 500 mhz varian ft-nmr spectrometers using the deuterated solvent as an internal standard. The reaction was quenched with triethylammonium bicarbonate (0. Reverse transcripts from rna containing ush and native utp. To meet these criteria, and provide added functionality to rna sequences, two uridine triphosphate building blocks, unh and ush, were prepared. Numerous examples exist where nucleic acids have been selected as aptamers for proteins or small molecules ( ), as well as for chemical manipulations, including those of nucleic acid ligases and polymerases ( ).
Filled triangle, utp transcription filled circle, unh transcription filled square, ush transcription. A pool of 60mer transcripts containing six uridines per sequence but no uridines in the reverse transcription primer binding site. Anion exchange hplc was performed using a beckman 421a controller with a beckman 163 detection unit set to 260 nm and a 4. The transcription reaction contained 5 mm each ntp and 35 mm mgcl and was analyzed after a 3 h incubation period. Samples were preheated at 95c for 5 min prior to analysis either using 20 or 10 denaturing page depending upon the length of the transcript. The solvent was removed by rotary evaporation, yielding 0. This construct exhibited 8090 efficiency for reverse transcription of ush rnas relative to rnas containing uridine (fig. Methods in enzymology, academic press, new york, 142 (1987) pp. However, both functioned in transcription assays of 100 nt templates to generate rna transcripts in quantities sufficient to initiate rna selection procedures. Sakthivel and barbas synthesized a series of 5-modified dutp analogs which included both cationic and anionic residues as well as ).Two analog uridine triphosphates tethering additional functionality, one a primary amino group and the second a mercapto group, were prepared and tested for ...