SOLUTION STRUCTURE OF A BIOLOGICALLY-ACTIVE CYCLIC LDV PEPTIDE ANALOGCONTAINING A TYPE II' BETA-TURN MIMETIC

The solution structure of cyclo-[Gly-Leu-Asp-Val-BTD] (BTD = p-turn di peptide) has been determined by two-dimensional H-1-NMR (nuclear magne tic resonance) spectroscopy and systematic conformational searching co mbined with molecular dynamics studies. The structure contains two hyd rogen bonds between the Gly and Val residues, and a type I beta-turn w ith Leu and Asp at the (i+1) and (i+2) positions of the turn, The cycl ic compound shows activity in a scintillation proximity assay (SPA) fo r the inhibition of the interaction between the integrin alpha(4) beta (1) and vascular cell adhesion molecule-1 (VCAM-1), The structure-acti vity relationship of the LDV sequence is discussed. (C) Munksgaard 199 6.