Synthesis and physicochemical characterization of fluorescent (E)‐2‐stilbenyloxyalkylthiouracils and isomer differentiation using EIMS

Abstract

Twelve new fluorescent (E)‐2‐stilbenyloxyalkylthiouracils and 6‐methyluracils 5a‐51 were prepared. EI induced mass spectral fragmentation of these compounds was investigated. Fragmentation pathways are proposed on the basis of accurate mass and metastable transition measurements. Correlation between the intensities of the M+ and the selected fragment ions of these compounds is discussed. The data obtained permit a distinction of the metamers. The 1H and 13C NMR spectra of these compounds were assigned unambiguously using a combination of heteronuclear (HETCOR) spectra and the chemical shifts. The data derived from these spectra can be used to differentiate the isomers.

From 2-Triethylammonium Ethyl Ether of 4-Stilbenol (MG624) to Selective Small-Molecule Antagonists of Human α9α10 Nicotinic Receptor by Modifications at the Ammonium Ethyl Residue

“…Mp = 130 °C. (coherent with the literature) 1 H NMR (300 MHz, CDCl 3 ) δ 7.55–7.40 (m, 4H), 7.35 (t, J = 7.5 Hz, 2H), 7.25 (m, 1H), 7.07 (d, J = 16.3 Hz, 1H), 6.98 (d, J = 16.3 Hz, 1H), 6.91 (d, J = 8.8 Hz, 2H), 4.32 (t, J = 6.3 Hz, 2H), 3.65 (t, J = 6.3 Hz, 2H).…”

“…Mp = 130 °C. (coherent with the literature 24 (E)-4-(2-Iodoethoxy)-stilbene (29). (E)-4-(2-bromoethoxy)-stilbene 28 (1.50 g, 4.95 mmol) was dissolved in 30 mL of a saturated solution of NaI in acetone and the reaction mixture was refluxed overnight.…”

Potent Antiglioblastoma Agents by Hybridizing the Onium-Alkyloxy-Stilbene Based Structures of an α7-nAChR, α9-nAChR Antagonist and of a Pro-Oxidant Mitocan

“…The intermediates 4b–i were synthesized according to a modified literature procedure . A solution of trans -4-hydroxy-stilbene (1 mmol) in DMSO (1.4 mL) was added to a stirred suspension of 85 mg of finely ground NaOH (2.1 mmol) in DMSO (5.6 mL).…”

Synthetic approaches toward stilbenes and their related structures

“…Compounds 220 were formed in 13-78% yield by the reaction of E-4-(bromoalkoxy)stilbenes 218 and were treated with piperidine, morpholine and 4-methylpiperidine 219 separately. E-4-(bromoalkoxy)stilbenes 218 were prepared by a reported procedure [87] as shown in Scheme 38.…”