Proceedings book download - 5Z.com

Table 1. GI 50 values (in µM) for quercetin derivatives 4-7CompoundGI 50 a (µM)Cell linesHCT 116 SW 620 MCF-74 >100 >100 >1005 ≥100 >100 ≥1006 ≥100 >100 >1007 78±16 >100 73±14a GI 50 ; the concentration that causes 50% growth inhibitionWhile BOP method was good for the preparation of compound 1b, in general for thepreparation of enkephalin derivatives of quercetin isobutylchloroformate was the betterchoice. The yields of protected compounds of quercetin with Leu/Met-enkephalin 1-3 werebetween 50-70%. Yields of the deprotected compounds were between 60-85%.According to the MS and NMR analysis position of the substitution in compounds 4-7was defined while in the case of compound 3a and 8 the position of second peptide isunknown, but MS analysis for compound 8 confirms that second peptide was bonded(HRMS MALDI [M+H]+; m/z=1377,56). Racemization of the activated amino acid in thereactions with isobutylchloroformate was between 9-18%, and in the reactions with BOP~52%.Interactions with ct-DNA of prepared compounds 4-7 were investigated usingUV/VIS, flurescence, and CD measurements, but no interactions were observed. Table 1shows results of the evaluation of antitumor activity on MCF-7 (brest carcinoma), SW 620(colon carcionoma), HCT 116 (colon carcinoma). Compound 7 shows modestantiproliferative activity, at highest tested concentration. Prepared compounds do notexhibit interactions with ct-DNA and do not have significant antitumor activity in spite ofour expectation based on starting compounds. Further investigation concerning antioxidativeand anti-bacterial activities will be conducted.AcknowledgmentsWe gratefully acknowledge the financial support of the Croatian Ministry of Science, Education andSports, Grants No. 098-0982933-2936, 098-0982914-2918 and 098-0982464-2514.References1. El, Gharras Int. J. Food Sci. Technol. 40, 2512-2518 (2010).2. Cheng, F., McLaughlin, P.J., Verderame, M.F., Zagon, I.S. Mol. Cancer 7, 5-16 (2008).3. Chen, D., Dou, Q.P. Int. J. Mol. Sci. 9, 1196-1206 (2008).323