title: The desoxazoline asidiacyclamide analogue cyclo(Gly-Thr-D-Val-Thz-Ile-Thr-D-Val-Thz) acetonitrile monosolvate.
abstract: THE TITLE PEPTIDE [SYSTEMATIC NAME: 4-(butan-2-yl)-7,20-bis-(1-hy-droxy-eth-yl)-10,23-bis-(propan-2-yl)-12,25-dithia-3,6,9,16,19,22,27,28-octa-aza-tricyclo-[22.2.1.1(11,14)]octa-cosa-1(26),11(28),13,24(27)-tetra-ene-2,5,8,15,18,21-hexone acetonitrile monosolvate], C(32)H(48)N(8)O(8)S(2)·CH(3)CN, an analogue of ascidiacyclamide (ASC) [cyclo(-Ile-Oxz-D-Val-Thz-)(2)], lies about a twofold rotation axis, so that the glycine (Gly) and isoleucine (Ile) residues are each disordered over two sites with equal occupancies. The acetonitrile mol-ecule is also located on a twofold axis passing through the C and N atoms. In the peptide, the thia-zole rings are faced to each other with a dihedral angle of 9.63 (15)° and intra-molecular N-H⋯O and O-H⋯O hydrogen bonds are observed. A bifurcated N-H⋯(O,O) hydrogen bond links the peptide mol-ecules into a layer parallel to the ab plane.
authors.affiliation: Osaka University of Pharmaceutical Sciences, Nasahara, Osaka 569-1094,  Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Asano
authors.forename: Mitsunobu
authors.initials: M
authors.lastname: Doi