Phosphoramidite

Abstract: A new class of nucleoside phosphoramidites which are relatively stable to permit isolation thereof and storage at room temperature. The phosphoramidites are derivatives of saturated secondary amines.

Abstract: The invention concerns 2,N 6 -disubstituted and 2,N 6 -trisubstituted adenosine nucleosides in which the sugar component is substituted at position 3' or position 5' by a phosphite or phosphoramidite group of the formula: ##STR1## R 1 representing a lower alkyl or --(CH 2 ) n --CN with n being an integer between 1 and 4, and X representing a halogen or an amine group. These nucleosides make it possible to prepare sequences of nucleotides usable, in particular, as probes in the field of analyses and biological extractions.

Abstract: Phosphoramidite derivatives of formula (V), ##STR1## wherein X is biotin and Y is a protecting group. There may be a linker arm, of variable length, between X and the rest of the molecule. Examples of the protecting group Y include 4,4'-dimethoxytrityl, trifluoroacetyl and fluorenylmethoxycarbonyl (Fmoc). The phosphoramidite derivatives are useful in single or multiple labelling of synthetic oligonucleotides. Process for the preparation of these phosphoramidite derivatives are also disclosed.

Abstract: Publisher Summary This chapter discusses the chemical synthesis of deoxy oligonucleotides by the phosphoramidite method. It discusses the synthesis methodology; detailed protocols for preparing the silica support, the phosphoramidite, and deoxy oligonucleotides; and the purification of synthetic deoxyribo nucleic acid (DNA). The phosphite triester approach to DNA synthesis using deoxynucleoside phosphoramidite as synthons has become the method of choice for the preparation of deoxy oligonucleotides. The general synthetic strategy involves adding mononucleotides sequentially to a deoxynucleoside, attached covalently to a silica-based insoluble polymeric support. Reagents, starting materials, and side products are then removed simply by filtration. At the conclusion of the synthesis, the deoxy oligonucleotide is chemically freed of blocking groups, hydrolyzed from the support, and purified to homogeneity by either polyacrylamide gel electrophoresis (PAGE) or high-performance liquid chromatography (HPLC). These preformed synthons are especially attractive for preparing DNA on automatic or semiautomatic DNA synthesizers, or for those who plan to manually synthesize a large number of deoxy oligonucleotides.