Synthesizer
Mostrando 13-24 de 43 artigos, teses e dissertações.
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13. Solid phase synthesis of oligoribonucleotides using the o-nitrobenzyl group for 2'-hydroxyl protection and H-phosphonate chemistry.
Oligoribonucleotides with chain length of 7, 11, 15, 17, 24 and 34 were synthesized on long chain alkylamine controlled pore glass beads (LCA-CPG) using o-nitrobenzyl protection of 2'-hydroxyls via a H-phosphonate approach either manually or by using an automatic synthesizer. The oligoribonucleotides were obtained in yields of 0.6 0.6-20%, based on initial n
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14. Incorporation of (R)- and (S)-3',4'-seco-thymidine into oligodeoxynucleotides: hybridization properties and enzymatic stability.
Novel flexible oligodeoxynucleotide analogues containing (R)- and (S)-3',4'-seco-thymidine were synthesized on an automated DNA-synthesizer using the phosphoramidite approach. Oligodeoxynucleotide analogues (17-mers) having one or three modifications in the middle or one or two modifications in the ends were evaluated with respect to hybridization properties
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15. 5'-Levulinyl and 2'-tetrahydrofuranyl protection for the synthesis of oligoribonucleotides by the phosphoramidite approach.
The levulinyl group has been employed for protection of the 5'-hydroxyl group in the synthesis of oligoribonucleotides by the phosphoramidite approach, using the acid-labile 2'-tetrahydro-furanyl group. The hydrazine treatment was performed for 10 minutes in order to remove the levulinyl group on controlled pore glass. Four decaribonucleotides (AAAAAAAAAU, G
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16. Solid phase synthesis of polynucleotides. VI. Further studies on polystyrene copolymers for the solid support.
A simple solid phase method for the synthesis of oligodeoxyribonucleotides has been developed using the phosphotriester approach. Mononucleotide coupling units are sequentially added to the polystyrene copolymer with 1% divinylbenzene and two kinds of oligonucleotides, d(CACGACCCCTCCACGT) and d(AACTGGTATTACTGGGCG), are synthesized in a relatively high yield.
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17. Site specific functionalization of oligonucleotides for attaching two different reporter groups.
The synthesis of an oligonucleotide functionalized to attach two different reporter groups at specific internucleotide linkages is described. To incorporate the amine specific reporter group the internucleotide linkage is modified to phosphoramidate (N-1-aminoalkyl) and for a thiol specific reporter group the internucleotide linkage is modified to a phosphor
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18. Rapid synthesis of oligodeoxyribonucleotides on a grafted polymer support.
Rapid synthesis of oligodeoxyribonucleotides is described by a solid phase method. Polysterene grafted on the surface of polytetrafluoroethylene has been found to be an adequate support. The properties of the support were studied in the synthesis of a number of oligonucleotides 6 to 15 nucleotides long. A flow-type semi-automatic synthesizer has been used. E
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19. Metalloselenonein, the selenium analogue of metallothionein: synthesis and characterization of its complex with copper ions.
We used an automated peptide synthesizer to produce a peptide, metalloselenonein, that contains selenocysteine residues substituted for all cysteine residues in Neurospora crassa copper metallothionein. Metalloselenonein binds 3 mol of Cu(I) per mol. This adduct shows a broad absorption band between 230 and 400 nm and a fluorescence band at 395 nm, which can
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20. Whole genome analysis: Experimental access to all genome sequenced segments through larger-scale efficient oligonucleotide synthesis and PCR
The recent ability to sequence whole genomes allows ready access to all genetic material. The approaches outlined here allow automated analysis of sequence for the synthesis of optimal primers in an automated multiplex oligonucleotide synthesizer (AMOS). The efficiency is such that all ORFs for an organism can be amplified by PCR. The resulting amplicons can
The National Academy of Sciences of the USA.
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21. Modification of guanine bases by nucleoside phosphoramidite reagents during the solid phase synthesis of oligonucleotides.
Nucleoside 3'-phosphoramidite and chlorophosphite reagents have been found to react with the lactam function of guanine. This reaction caused unsatisfactory results when oligodeoxyribonucleotides containing a large number of guanine bases were prepared in an automated solid phase synthesizer. The guanine modification is unstable, and leads to depurination an
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22. Gene Expression Analysis Using Oligonucleotide Arrays Produced by Maskless Photolithography
Microarrays containing 195,000 in situ synthesized oligonucleotide features have been created using a benchtop, maskless photolithographic instrument. This instrument, the Maskless Array Synthesizer (MAS), uses a digital light processor (DLP) developed by Texas Instruments. The DLP creates the patterns of UV light used in the light-directed synthesis of olig
Cold Spring Harbor Laboratory Press.
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23. Application of 2-cyanoethyl N,N,N',N'-tetraisopropylphosphorodiamidite for in situ preparation of deoxyribonucleoside phosphoramidites and their use in polymer-supported synthesis of oligodeoxyribonucleotides.
Deoxyribonucleoside phosphoramidites are prepared in situ from 5'-O,N-protected deoxyribonucleosides and 2-cyanoethyl N,N,N',N'-tetraisopropylphosphorodiamidite with tetrazole as catalyst, and the solutions applied directly on an automatic solid-phase DNA synthesizer. Using LCAA-CPG support and a cycle time of 12.5 min, oligonucleotides of 16-25 bases are ob
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24. Preparation and hybridization properties of oligonucleotides containing 1-alpha-D-arabinofuranosylthymine.
A pentadecanucleotide was prepared from 1-alpha-arabinofuranosylthymine. This novel oligonucleotide was found to hybridize to oligodeoxyadenylate, although not a s strongly as pentadecathymidylate. It formed duplex hybrids with both DNA and RNA complements, and triplex structures with a duplex containing a (dT)15-(dA)15 tract within a more complex strand. Th