1. Optimized synthesis of aminooxy-peptides as glycoprobe precursors for surface-based sugar-protein interaction studies
Carmen Jiménez-Castells, Beatriz G de la Torre, Ricardo Gutiérrez Gallego, David Andreu Bioorg Med Chem Lett. 2007 Sep 15;17(18):5155-8. doi: 10.1016/j.bmcl.2007.06.090. Epub 2007 Jul 5.
An improved procedure for solid phase coupling of Boc-aminooxyacetic acid to peptides is described. By avoiding base-containing activation mixtures which cause over-acylation, it practically suppresses this unwanted side reaction and leads to near quantitative yields of Aoa-peptides, useful as glycoprobe precursors in glycomic studies.
2. Development of novel 68Ga- and 18F-labeled GnRH-I analogues with high GnRHR-targeting efficiency
Margret Schottelius, Sebastian Berger, Thorsten Poethko, Markus Schwaiger, Hans-Jürgen Wester Bioconjug Chem. 2008 Jun;19(6):1256-68. doi: 10.1021/bc800058k. Epub 2008 May 30.
A large majority of tumors of the reproductive system express the gonadotropin releasing hormone receptor (GnRHR). Blockade and activation of this receptor with various antagonistic and agonistic analogues of native GnRH-I (pGlu(1)-His(2)-Trp(3)-Ser(4)-Tyr(5)-Gly (6)-Leu(7)-Arg(8)-Pro(9)-Gly(10)-NH2), respectively, has shown efficient suppression of tumor growth. In this study, the GnRH-receptor system has been evaluated with respect to its suitability as a target for in vivo peptide receptor targeting using radiolabeled GnRH-analogues, and in parallel, new (18)F- and (68Ga)-labeled GnRH analogues have been developed. In vitro radioligand binding assays performed with various GnRHR-expressing human cell lines using [(125)I]Triptorelin (D-Trp(6)-GnRH-I) as the standard radioligand revealed a very low level of GnRH receptor expression on the cell surface.
