79873-93-1 GF 109 GF-109 L-Proline, 3,4-didehydro-1-(1-(N-(N2-(1-(N2-(3,4-didehydro-1-(N-L-alpha-glutamyl-L-tryptophyl)-L-prolyl)-L-arginyl)-L-prolyl)-L-glutaminyl)-L-isoleucyl)-L-prolyl)-