The preparative method for 2-fluoroadenosine synthesis

Abstract

The preparative method for the synthesis of 2-fluoroadenosine starting from commercially available guanosine was developed. It included the intermediate formation of 2-amino-6-azido-9-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)purine, which was isolated exclusively in the tetrazolo[5,1-i]-form {5-amino-7-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)-7H-tetrazolo[5,1-i]purine}. The latter compound was converted by the Schiemann reaction to 6-azido-2-fluoro-9-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)purine, which was isolated at an 80% yield after careful optimization of the process. The IR and 1H NMR spectroscopy data indicated the 6-azido-2-fluoropurine structure of the aglycone. The catalytic reduction of the azido group in 6-azido-2-fluoro-9-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)purine to the amino moiety and the subsequent deacetylation by the routine procedure resulted in 2-fluoroadenosine at a total yield of 74%.

Multi-Enzymatic Cascades in the Synthesis of Modified Nucleosides: Comparison of the Thermophilic and Mesophilic Pathways

“…The starting compound for the preparation of 2-fluoro-6-methoxypurine ( 7 ) was 2-amino-6-chloropurine riboside triacetate ( 4 ), obtained by the method [ 27 ]. The substitution of the 2-amino group with fluorine was performed by the action of 70% HF in pyridine ( Figure 6 ).…”

“…9-(2,3,5-Tri-O-acetyl-β-D-ribofuranosyl)-2,6-dichloropurine was synthesized as described in [ 25 , 26 ]. 9-(2,3,5-Tri-O-acetyl-β-D-ribofuranosyl)-2-amino-6-chloropurine was synthesized as described in [ 27 ].…”

Enzymatic Synthesis of 2-Chloropurine Arabinonucleosides with Chiral Amino Acid Amides at the C6 Position and an Evaluation of Antiproliferative Activity In Vitro

“…Chemical modifications of purine are known to be more convenient to carry out in a nucleoside (where the N9 position of purine is protected by a carbohydrate residue) instead of a heterocyclic base [ 24 , 25 ]. The classical method for obtaining arabinonucleosides is the glycosylation of a modified purine base with a protected carbohydrate derivative [ 26 , 27 , 28 , 29 ] or complex ribose modifications [ 30 , 31 ].…”

Component Composition of Essential Oils <i>Curcuma longa</i> L. (Zingiberaceae) Introduced in Uzbekistan

“…The main active substances are curcuminoids, and three dominant ones are distinguished from them: curcumin, desmethoxycurcumin and bisdemethoxycurcumin; a certain contribution is made by the terpenoid complex of the plant [8] [9].…”