Highly chemoselective palladium-catalyzed Sonogashira coupling of 5-iodouridine-5′-triphosphates with propargylamine: a new efficient method for the synthesis of 5-aminopropargyl-uridine-5′-triphosphates

An improved protection-free one-pot chemical synthesis of purine locked nucleic acid nucleoside-5'-triphosphates

A simple, reliable, straightforward, and efficient method for the gram-scale chemical synthesis of purine locked nucleic acid (LNA) nucleotides such as LNA-guanosine-5'-triphosphate (LNA-GTP) and LNA-adenosine-5'-triphosphate (LNA-ATP) starting from the corresponding nucleoside is described. The overall reaction utilizes an improved "one-pot, three-step" Ludwig synthetic strategy that involves the monophosphorylation of LNA nucleoside, followed by the reaction with tributylammonium pyrophosphate and subsequent hydrolysis of the resulting cyclic intermediate using water to furnish the corresponding purine LNA nucleotide in good yield with high purity (>99.5%).

Highly regioselective 1,3-dipolar cycloaddition of 3'-O-propargyl guanosine with nitrile oxide: An efficient method for the synthesis of guanosine containing isoxazole moiety

The 1,3-dipolar cycloaddition reaction of 3'-O-propargyl guanosine with various in-situ generated nitrile oxides in the presence of DMF as a solvent is described. It is noteworthy that the reaction is highly regioselective that affords biologically important guanosine containing isoxazole moiety in good yields with high purities.

Highly regioselective methylation of inosine nucleotide: an efficient synthesis of 7-methylinosine nucleotide

A facile, straightforward, reliable, and an efficient chemical synthesis of inosine nucleotides such as 7-methylinosine 5'-O-monophosphate, 7-methylinosine 5'-O-diphosphate, and 7-methylinosine 5'-O-triphosphate, starting from the corresponding inosine nucleotide is delineated. The present methylation reaction of inosine nucleotide utilizes dimethyl sulfate as a methylating agent and water as a solvent at room temperature. It is noteworthy that the present methylation reaction proceeds smoothly under aqueous conditions that is highly regioselective to afford exclusive 7-methylinosine nucleotide in good yields with high purity (>99.5%).

An efficient protection-free chemical synthesis of inosine 5'-nucleotides

A facile, straightforward, reliable, and efficient chemical synthesis of inosine nucleotides such as inosine-5'-monophosphate, inosine-5'-diphosphate, and inosine-5'-triphosphate, starting from inosine is delineated. The inosine-5'-monophosphate is achieved by the highly regioselective monophosphorylation of inosine using the Yoshikawa procedure. The inosine-5'-diphosphate is obtained by the coupling reaction of tributylammonium phosphate with an activated inosine-5'-monophosphate using zinc chloride as a catalyst. The inosine-5'-triphosphate is efficiently achieved by the improved "one-pot, three-step" Ludwig synthetic strategy. In all the cases, the resulting final product is isolated in good yields with high purity (>99.5%).

An Efficient Synthesis of 5-Aminopropargyl-Pyrimidine-5'-O-Triphosphates Through Palladium-Catalyzed Sonogashira Coupling

The utilization of 5-aminopropargyl nucleotide serves as a versatile molecular biology tool for the introduction of functional groups into a nucleic acid target of interest by using in-vitro enzymatic incorporation method. This article describes a simple, reliable, general, and efficient two-step chemical method for the synthesis of 5-(3-aminopropargyl)-2'-deoxycytidine-5'-O-triphosphate, 5-(3-aminopropargyl)-cytidine-5'-O-triphosphate, 5-(3-aminopropargyl)-2'-deoxyuridine-5'-O-triphosphate, and 5-(3-aminopropargyl)-uridine-5'-O-triphosphate, starting from the corresponding pyrimidine triphosphate. The first step involves regioselective C-5 iodination of pyrimidine triphosphate using N-iodosuccinimide and sodium azide. In the second step, propargylamine is coupled to the iodo-pyrimidine using the palladium-catalyzed Sonogashira reaction, producing good yields of highly pure (>99.5% HPLC) 5-aminopropargyl-pyrimidine-5'-O-triphosphate. In this approach, the palladium-catalyzed Sonogashira coupling reaction is highly chemoselective and does not involve protection and deprotection. © 2019 by John Wiley & Sons, Inc.

An Efficient Protection-Free One-Pot Chemical Synthesis of Modified Nucleoside-5'-Triphosphates

A simple, reliable, and an efficient "one-pot, three step" chemical method for the synthesis of modified nucleoside triphosphates such as 5-methylcytidine-5'-triphosphate (5-MeCTP), pseudouridine-5'-triphosphate (pseudoUTP) and N(1)-methylpseudouridine-5'-triphosphate (N(1)-methylpseudoUTP) starting from the corresponding nucleoside is described. The overall reaction involves the monophosphorylation of nucleoside, followed by the reaction with pyrophosphate and subsequent hydrolysis of the cyclic intermediate to furnish the corresponding NTP in moderate yields with high purity (>99.5%).

Concise and efficient synthesis of 3'-O-tetraphosphates of 2'-deoxyadenosine and 2'-deoxycytidine

We describe concise and efficient synthesis of biologically very important 3'-O-tetraphosphates namely 2'-deoxyadenosine-3'-O-tetraphosphate (2'-d-3'-A4P) and 2'-deoxycytidine-3'-O-tetra-phosphate (2'-d-3'-C4P). N(6)-benzoyl-5'-O-levulinoyl-2'-deoxyadenosine was converted into N(6)-benzoyl-5'-O-levulinoyl-2'-deoxyadenosine-3'-O-tetraphosphate in 87% yield using a one-pot synthetic methodology. One-step concurrent deprotection of N(6)-benzoyl and 5'-O-levulinoyl groups using concentrated aqueous ammonia resulted 2'-d-3'-A4P in 74% yield. The same synthetic strategy was successfully employed to convert N(4)-benzoyl-5'-O-levulinoyl-2'-deoxycytidine into 2'-d-3'-C4P in 68% yield.

A new efficient stereoselective method for the synthesis of (E)-5-aminoallyl-pyrimidine-5'-triphosphates using palladium-catalyzed Heck reaction

An efficient overall two-step strategy for the synthesis of (E)-5-aminoallyl-pyrimidine-5'-triphoshate, starting from commercially available pyrimidine-5'-triphosphate is described. The method involves regioselective iodination of pyrimidine-5'-triphosphate, followed by the palladium-catalyzed Heck coupling with allylamine. The catalytic reaction is highly stereoselective and compatible with many functional groups present in the reactants.

Highly regioselective C-5 iodination of pyrimidine nucleotides and subsequent chemoselective Sonogashira coupling with propargylamine

An efficient C-5 iodination of pyrimidine-5'-triphosphates and subsequent palladium-catalyzed Sonogashira coupling reaction with propargylamine is described. The iodination reaction is highly regioselective and the coupling reaction is highly chemoselective that furnishes exclusive 5-(3-aminopropargyl)-pyrimidine-5'-triphosphate in good yield with high purity (>99%).

Short and straightforward synthesis of triphosphates of artificial nucleobase pairs displaying unconventional pairing scheme

Concise, facile and efficient synthesis of 5'-O-triphosphates of 6-amino-5-nitro-3-(1'-β-D-2'-deoxyribofuranosyl)-2(1H)-pyridone (dZ) and its Watson-Crick complement 2-amino-8-(1'-β-D-2'-deoxyribofuranosyl)-imidazo[1,2a]-1,3,5-triazin-4(8H)-one (dP) is reported using a one-pot synthetic procedure.

Facile protection-free one-pot chemical synthesis of nucleoside-5'-tetraphosphates

A new, straightforward, reliable, and convenient protection-free one-pot method for the synthesis of 2'-deoxynucleoside-5'-tetraphosphate and ribonucleoside-5'-tetraphosphate is reported. The present synthetic strategy involves the monophosphorylation of a nucleoside followed by reaction with tris-(tri-n-butylammonium) triphosphate and subsequent hydrolysis of the putative cyclic tetrametaphosphate intermediate to provide nucleoside-5'-tetraphosphate in moderate yield with high purity. A plausible mechanism is proposed to account for the formation of product.

Facile protection-free one-pot synthesis of 7-deaza-2′-deoxyguanosine-5′-triphosphate — A versatile molecular biology probe

A simple, straightforward, reliable, and efficient protection-free “one-pot, three-step” chemical synthesis of 7-deaza-2′-deoxyguanosine-5′-triphosphate (7-deaza-dGTP) is described. The reaction involves monophosphorylation of 7-deaza-2′-deoxyguanosine using phosphorous oxychloride as the phosphorylating agent, followed by reaction with tributylammonium pyrophosphate, and subsequent hydrolysis affords 7-deaza-2′-deoxyguanosine-5′-triphosphate in a 52% yield with high purity (>99.9%).