1. 1) Ladouceur G. H., Bear B., Bi C., Brittelli D. R., Burke M. J., Chen G., Cook J., Dumas J., Sibley R., Turner M. R., WO 2004043950 (2004).
2. 2) Inhibitory effect of 9 toward the VEGF-induced proliferation of human glomerular endothelium cells in vitro [IC50 (μmol/l)=0.04]. Inhibitory effect of 9 toward the VEGF-induced auto-phosphorylation with human umbilical vein endothelial cells in vitro [IC50 (μmol/l)=0.02]. Inhibitory effect of the derivative 9 on VEGF-induced dye leakage in rat skin (7 week-old male Wistar rats were used in this study) [70% against control at 25 mg/kg p.o.].
3. Potent Platelet-Derived Growth Factor-.BETA. Receptor (PDGF-.BETA.R) Inhibitors: Synthesis and Structure-Activity Relationships of 7-[3-(Cyclohexylmethyl)ureido]-3-{1-methyl-1H-pyrrolo[2,3-b]pyridin-3-yl}quinoxalin-2(1H)-one Derivatives
4. 5) Similar indolenine and/or direct pathway as in the mechanism of Pictet–Spengler reaction may be engaged in this TFA-promoted coupling process of 3-substituted indoles with quinoxalin-2-ones. For review on discussion about this mechanism, see: Enrique L. L., Marcela A., Andrea B. J. B., Teodoro S. K., ARKIVOC. Issue in Honor of Prof. Rosa Lederkremer, (xii), 98—153 (2005).