“Chemical Ligation”: A Versatile Method for Nucleoside Modification with Boron Clusters

Abstract

A general approach to the synthesis of nucleoside conjugates containing carborane and metallocarborane complexes, based on Huisgen 1,3-dipolar cycloaddition ("chemical ligation"), is described. Boron-cluster-donors bearing terminal azide or ethynyl groups were prepared in the ring-opening reaction of dioxane-boron-cluster adducts and an azide anion or suitable alkynol-derived alcoholate nucleophile. Analogous derivatives bearing terminal sulfhydryl groups were also prepared. Nucleosides with various spacers containing terminal azide or ethynyl groups, located within nucleobases or sugar residues, were used as boron-cluster acceptors. The proposed methodology provides a convenient way to synthesize libraries of boron-cluster-modified nucleosides for various applications.

DNA probe modified with 3-iron bis(dicarbollide) for electrochemical determination of DNA sequence of Avian Influenza Virus H5N1

“…3-Iron bis(dicarbollide) redox label was covalently attached to DNA probe using "click chemistry" methodology (El-Sagheer and Brown, 2010;Wojtczak et al, 2008) in the manner providing its location close to the surface of gold electrode. This is in contrast to redox active labels and formats reported till now.…”

Synthesis of closo-dodecaborate based nucleoside conjugates

“…Recently a general method was proposed for the synthesis of nucleoside libraries bearing carborane or metallacarborane modification for biochemical screening using Huisgen 1,3-dipolar cycloadition of azides and terminal alkynes, a ''click" chemistry approach [13]. It was found that also B 12 -based azides undergo Cu I -catalyzed ''click" reactions with various alkynes leading to corresponding triazoles in high yields [12].…”

“…11 B NMR (ppm): 6.3 (1B, s, B(1)); À16.8 (5B, d, B(2-6)); À18.2 (5B, d, B(7-11)); À22.5 (1B, d, B (12)). 13 C NMR (ppm): 163.1 (C-4); 150.8 (C-2); 135.3 (C-6); 108.9 (C-5); 87.8 (C-4 0 ); 85.2 (C-1 0 ); 71.1 (C-3 0 ); 70.7, 68.1, 66.9 (CH 2 O-spacer); 61.6 (C-5 0 ); 58.0 (NCH 2 CH 2 CH 2 CH 3 ); 41.2 (CH 2 N-spacer); 39.9 (C-2 0 ); 23.5 (NCH 2 -CH 2 CH 2 CH 3 ); 19.7 (NCH 2 CH 2 CH 2 CH 3 ); 13.9 (NCH 2 CH 2 CH 2 CH 3 ); 13.4 (5-CH 3 ).…”

“…Oxonium derivative 2, azide 5 and 3N-(4-pentyn-1-yl)thymidine 6 were prepared according to the described methods [11][12][13]. The 1 H, 13 100.61 and 128.38 MHz, respectively, on a BRUKER-Avance-400 spectrometer in DMSO-d 6 (3,4,7) or in D 2 O (4a). Tetramethylsilane and BF 3 /(C 2 H 5 ) 2 O were used as standards for 1 H and 13 C NMR, and 11 B NMR, respectively.…”

Synthesis of cobalt bis(dicarbollide) conjugates with natural chlorins by the Sonogashira reaction

“…Compound 2 was synthesized by the modification of a described procedure. 33 A freshly prepared solution of sodium propynolate (3 mg of sodi um per 1 mL of propargyl alcohol) was added at 0 °С to a solution of compound 1 (41 mg, 0.1 mmol) in acetonitrile (10 mL), and the mixture was left for 48 h. The reaction course was monitored by TLC. Water (100 μL) was added after the end of the reaction.…”