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Updated: May 24, 2026

Synthesis and Bioconjugation of Thiol-Reactive Reagents for the Creation of Site-Selectively Modified Immunoconjugates
Published on: March 6, 2019
3,3'-Dibenzoyl-1,1'-dibenzyl-1,1'-(ethane-1,2-di-yl)-dithio-urea
Andrzej Okuniewski1, Jaroslaw Chojnacki, Barbara Becker
1Department of Inorganic Chemistry, Gdansk University of Technology, 11/12 Narutowicza Street, 80-233 Gdańsk, Poland.
Abstract:
In the title compound, C(32)H(30)N(4)O(2)S(2), the carbonyl and thio-carbonyl groups are found in a rare synclinal conformation, with an S-C⋯C-O pseudo-torsion angle of 62.6 (2)°. The mol-ecule has C(i) = S(2) point-group symmetry with a crystallographic center of inversion located in the middle of the ethyl-ene bridge. One of the symmetry-independent phenyl rings is disordered over two orientations, with a site-occupation ratio of 70:30. The distances between the centroids of the nearest phenyl rings are equal to one of the lattice constants [a = 4.7767 (2) Å], so stacking inter-actions are extremely weak. Mol-ecules are joined by bifurcated hydrogen bonds (N-H⋯O and N-H⋯S), forming a ladder-like arrangement along [100]. van der Waals forces combine these ladders into a three-dimensional structure. The dependency between the S⋯O distance and the improper S=C⋯C=O torsion angle based on 739 structures containing the CC(=O)NC(=S)N moiety is discussed.
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