Synopsis: This compound, two Oxz residues of asciduacyclamide were replaced with D-aThr and (2R,3S)-Oxz (D-Oxz). The overall structure is similar to the folded from of ASC analogues previously reported, but a difference was found at the D-Oxz residue. The D-Oxz ring was turned over in relation to the disposition of the Oxz rings in natural ASC.

P a p e r

Turn-over of an oxazoline ring induced by chiral change of a folded ascidiacyclamide analogue: cyclo(Ile-D-aThr-D-Val-Thz-Ile-D-Oxz-D-Val-Thz) N,N-dimethylformamide disolvate. Akiko Asano and Mitsunobu Doi Acta Cryst. E60 (4), o2449-o2451 (2004). Copyright © International Union of Crystallography

Structure of title compound	Superimosition with [Ala]ASC Oxz ring was turned over
Picuters and fitting were produced by iMol

     Formula         C36H54N8O7S2        Wavelength      0.7107
     Solvation       2(C3H7NO)           μ               0.172
     Mr              921.18              NREF (obs)      20955
     System          monoclinic          Rint            0.0259 
     Space group     P21                 NREF (used)     10109
     a               13.0313(11)         θmax            27.1
     b               11.0503(9)          Flack           0.04(7)
     c               17.3576(14)         R               0.0522
     β               104.6540(10)        wR              0.1386 
     V               2418.2(3)           Goodness        1.031
     Z               2                   (Δ/σ)max        0.013
     T, K            120                 Fraction        0.986
     Dx,             1.265               Δρmax           0.798
     F(0 0 0)        988                 Δρmin           -0.521

     PDB coord.      here

the structure index