(2-Quinoxalinecarbonyl)-Thr-Ile-Nle.psi.[COCH2]-(D or L)-2-Nal-Gln-Arg-NH2 AIDS-082244 AIDS082244 Qui-Thr-Ile-Nle.psi.[COCH2]-(D or L)-2-Nal-Gln-Arg-NH2