Tions (Figures S1 and S3). The structure of 2 comprises ethanol solvent molecules that show positional disorder. Compound 4 crystallizes in the monoclinic space group, P21 /c, and an asymmetric unit consists of 1 Er complex inside a common position (Aztreonam Epigenetic Reader Domain Figure S5). Compounds 5 and 6 crystallize in the orthorhombic space group, Cmc21 , with half with the formula unit per asymmetric unit; both the cation and anion are positioned in partial positions on a mirror plane, and one particular ethylene group from the cation is disordered about this plane (Figure S9). Complexes five and 6 are isostructural to every single other and to the previously reported Dy and Tb analogues [53]. The crucial bond distances and angles in the structures investigated are listed in Table S2 (for 2), S4 (3), S6 (4), and S8 (5 and six). The molecular structures from the complexes are shown in Figures 1. In each of the structures, the central 4f -metal (Er, or Y in six) is seven-coordinated by 3 N and two O atoms in the equatorial plane of the chelating pentadentate ligand, and two atoms (Cl, and N or O) in the axial ligands, Cl- , N3 – , and H2 O, CH3 OH or C2 H5 OH. The DAPMBH/H2 DAPS ligand is deprotonated on each N web-sites and includes a two-charge state. The Er(III) complexes are neutral if among the axial ligands is negatively charged (2), or anionic if they include two negatively charged Cl- axial ligands in addition to a (Et3 H)N counterion (5, six). There are no noticeable variations inside the bond length values within the Er polyhedrons for complexes with diverse charges (Table S9). The Er-Oequatorial and Er-Nequatorial bond lengths towards the pentadentate ligand in two are within the range of 2.22.28 and 2.40.45 respectively. The Er-Oaxial bond lengths for the axial ligands in the neutral complexes, 2, with H2 O/CH3 OH ligands, range among two.27 and 2.33 The Er-Naxial and Er-Claxial bond lengths are two.23 and 2.59.66 respectively. The DAPMBH and H2 DAPS ligands are not rather planar: the dihedral angle in JPH203 supplier between the two semicarbazone planes in the ligand, defined by seven nonmetallic atoms of two pentagonal cycles (one example is, O1, C8, N1, N2, C10, C11, N3, and O2, C18, N5, N4, C16, C15, N3 in Figure S1) is 4.02(8) in two, six.74(5) in three, and 6.0(2) in four. The same angle in the H2 DAPS ligand is five.3(two) in 5, and 5.four(1) in 6.Molecules 2021, 26,six ofIn all structures, the metal complexes are well-isolated molecular units. Their contacts with neighboring complexes, and with incorporated counterions or solvent molecules, are mediated by hydrogen bonding and/or -stacking [579] (Figures S2, S4, S6 8, S10 and S11). The hydrogen bonding can consolidate the adjacent metal complexes into dimeric or chain assemblies. H-bonded infinite chains with the Er complexes are identified in the structure of three. Along the chain, O-H . . . Cl bridges (with a H . . . Cl distance of two.33 involving the MeOH and Cl ligands of the adjacent Er units are formed, as well as the Er . . . Er intrachain distance is 7.0338(two) (Figure 5). -stacking is observed only involving the chains (Figure S4b).Figure 5. Infinite chain of hydrogen-bonded Er complexes in 3. Er . . . Er intrachain distance is 7.0338(2) Hydrogen-bonded centrosymmetric dimers are located in the structures of two and 4. In 2, two Er complexes are connected via a pair of equivalent hydrogen O(5)H2O -H . . . N(1)DAPMBH bonds (H . . . N of 1.98 , with an Er . . . Er intradimer separation of 7.0386(four) (Figure S2 and Figure six). The – interactions are observed each inside and involving the dimers (C . . . C intradimer distances significantly less th.
