On Novel Fluorine Reagents in Preparative Organic Chemistry

Adamantane-Substituted Purine Nucleosides: Synthesis, Host–Guest Complexes with β-Cyclodextrin and Biological Activity

“…To optimize this step, we carried out a series of reactions under different conditions (catalysator, solvent, temperature) [ 41 , 42 , 43 ] with model compounds 4 and 7 . During the optimization, we achieved the best results using modified Hilbert–Johnson glycosylation [ 44 ] under catalysis with trimethylsilyl trifluoromethanesulfonate (TMSOTf) in CH 3 CN at room temperature (hereinafter referred to as “method A”), and two-step Vörbruggen glycosylation [ 45 ] using N , O -bis(trimethylsilyl)acetamide (BSA) followed by glycosylation with TMSOTf in CH 3 CN at 75 °C (hereinafter referred to as “method B”). Interestingly, we obtained the desired compounds in different yields, depending on the substitution of the starting purine at the C2 position.…”

“…Compounds 10 – 15 were prepared following modified literature procedures, hereinafter referred to as “method A” [ 44 ] and “method B” [ 45 ], respectively.…”

[18F]Fluoropyruvate: radiosynthesis and initial biological evaluation

“…Simple standard sulfonation methods on the alcohol 5 gave the desired precursors with the mesylate 6 (97%), tosylate 7 (59%), and triflate 8 (85%) leaving groups. The precursor with the nonaflate 9 leaving group was isolated from unsuccessfully attempts to make the cold fluorine‐19 reference compound of 10 using the Vorbrüggen fluorination methodology . The radiofluorination was explored using standard radiofluorination methods using Kryptofix 2.2.2 (K 222 , 5 mg) as the phase transfer catalyst and potassium carbonate (1 mg) as the base.…”