The present invention pertains to a method for synthesizing a ribonucleic acid H-phosphonate monomer, and a method for performing oligonucleotide synthesis in which said monomer is used. The present invention pertains to a method for manufacturing an inexpensively manufacturable H-phosphonate nucleoside derivative in which selective protection is provided to position 2′ of a ribonucleoside monomer required in RNA oligonucleotide synthesis. The present invention is characterized in that: hydroxyl groups in position 2′ and position 3′, which have slightly different reactivity, are caused to react with an aromatic acyl halide at low temperature to selectively esterify position 2′; and subsequently the hydroxyl group at position 3′ in one pot is captured by a phosphityl group to prevent position 2′ and position 3′ transfer of the acyl group.

The present invention pertains to a method for synthesizing a ribonucleic acid H-phosphonate monomer, and a method for performing oligonucleotide synthesis in which said monomer is used. The present invention pertains to a method for manufacturing an inexpensively manufacturable H-phosphonate nucleoside derivative in which selective protection is provided to position 2′ of a ribonucleoside monomer required in RNA oligonucleotide synthesis. The present invention is characterized in that: hydroxyl groups in position 2′ and position 3′, which have slightly different reactivity, are caused to react with an aromatic acyl halide at low temperature to selectively esterify position 2′; and subsequently the hydroxyl group at position 3′ in one pot is captured by a phosphityl group to prevent position 2′ and position 3′ transfer of the acyl group.

Nicotinamide ribose has many applications, including as a dietary supplement. This invention convers a process to prepare nicotinamide ribose it in its phosphorylated form. The instant invention is based on the discovery that nicotinamide ribose phosphate emerges in stable form by direct reaction of ribose-1,2-cyclic phosphate. It is based on the further conversion of the phosphorylated nicotinamide ribose product to unphosphorylated nicotinamide ribose upon treatment with an enzymatic phosphatase, most preferably in buffer containing borate. It is based on the further discovery that compositions of nicotinamide ribose with borate slow the decomposition of nicotinamide ribose, and therefore is more useful than compositions of nicotinamide ribose without borate.

Various nucleoside phosphate and phosphonate analogues are provided for treatment of viral infections. Methods of preparing the analogues, pharmaceutical compositions containing the analogues, and methods of using the analogues as antiviral compounds, especially against adenoviruses, coronaviruses, and varicella zoster viruses, are also provided.

The present invention is a process for the preparation of certain 5′-phosphoramidate nucleotide diastereoisomers. The phosphoramidates include those useful in the treatment of cancer such as NUC-3373 (5-fluoro-2′-deoxyuridine-5′-O-[1-naphthyl(benzyloxy-L-alaninyl)]phosphate].

The present invention is a process for the preparation of certain 5′-phosphoramidate nucleotide diastereoisomers. The phosphoramidates include those useful in the treatment of cancer such as NUC-3373 (5-fluoro-2′-deoxyuridine-5′-O-[1-naphthyl(benzyloxy-L-alaninyl)]phosphate].

The present invention relates to methods of synthesis of stereodefined oligonucleotides wherein the protected 5′-hydroxy terminus of a nucleoside or oligonucleotide attached to a solid support is first unprotected, followed by coupling an oxazaphospholidine phosphoramidite monomer to the now deprotected 5′-hydroxy terminus, oxidizing the resultant phosphite triester intermediate with a sulfurizing reagent, and optionally washing the product. The method of synthesis of the present invention described above may be repeated to optionally elongate the stereodefined oligonucleotide being synthesized until the elongation cycle is intentionally terminated via deprotecting and cleavaging the resulting stereodefined oligonucleotide from the solid support. The oxazaphospholidine phosphoramidite monomer to be coupled in the present invention may optionally be chosen from Formula 1a and 1b. Generally, the present invention relates to enhanced synthesis methods wherein a single elongation cycle, optionally comprising repeated coupling and oxidation steps, results in an enhanced yield and higher purity of stereodefined phosphorothioate oligonucleotides.

Disclosed herein are novel catalysts for producing remdesivir in one-pot manner, in which a diastereomerically enriched form of an intermediate, which following acidic hydrolysis would give rise to the desired remdesivir, was produced with the aid of the disclosed novel catalysts. Also disclosed herein is an improved process for the preparation of remdesivir without the need to separate one of the enantiomers while minimizing the formation of undesired isomers, thus offers economic advantages for operation on a commercial scale.

Disclosed herein are novel catalysts for producing remdesivir in one-pot manner, in which a diastereomerically enriched form of an intermediate, which following acidic hydrolysis would give rise to the desired remdesivir, was produced with the aid of the disclosed novel catalysts. Also disclosed herein is an improved process for the preparation of remdesivir without the need to separate one of the enantiomers while minimizing the formation of undesired isomers, thus offers economic advantages for operation on a commercial scale.

The present application relates to a method for prepare a Cangrelor tetrasodium salt, comprising: using N-[2-(methylthio)ethyl]-2-[(3,3,3-trifluoropropyl)sulfonyl]adenosine as a raw material to undergo two steps of reaction to obtain a reaction solution containing the Cangrelor tetrasodium salt; separating and purifying once by C18 silica gel column chromatography so as to obtain a Cangrelor tetrasodium salt pure product. The present application has the advantages of short synthesis route, mild reaction conditions, sufficient reaction, simple operation, high product yield, high purity, and environmental friendliness, and is suitable for large-scale preparation.