Interaction of pentaphenylantimony with n-(4-methoxyphenyl)phthalamic acid

Pentaphenylantimony reacts with N-(4-methoxyphenyl)phthalamic acid in benzene at room temperature to form colorless crystals of tetraphenylantimony carboxylate solvated by benzene Ph4SbOC(O)C6H4[2-C(O)NHC6H4(OMe-4)]∙1½ PhH (1a, b), the structure of which is proven by X-ray diffraction analysis (XRD). According to the X-ray diffraction data, the antimony atoms in two crystallographically independent molecules 1a,b have the coordination of a distorted trigonal bipyramid with three phenyl substituents in the equatorial plane, while the CSbO axial angles are 173.7(2)° and 179.0(2)°, and the Sb-Ceq bond lengths are 2.103(7)-2.123(7) Å (1a), 2.106(6)-2.114(6) Å (1b), which is significantly less than the Sb-Cax distances (2.184(7) Å (1a) and 2.155(6) Å (1b)). The molecules of the benzene solvate are disordered. The Sb-O bond lengths (2.235(4) Å (1a) and 2.257(4) Å (1b)) are slightly larger than the sum of the covalent radii of antimony and oxygen atoms (2.07 Å). The X-ray diffraction data: (1) (D8 Quest diffractometer from Bruker (MoKα radiation, λ = 0.71073 Å, graphite monochromator) at 293(2) K [C78H64N2O8Sb2, M = 1400.81; monoclinic system, space group C2/c; crystal size 0.34 ´ 0.13 ´ 0.13 mm; cell parameters: a = 40.68(2) Å, b = 10.492(5) Å, c = 36.395(17) Å; β = 100.30(2)°, V = 15283(13) Å3, Z = 8; rcalc = 1.218 g/cm3; m = 0.758 mm-1; F(000) = 5696.0; collection area according to 2q: 5.68-54.3°; -48 ≤ h ≤ 52, -13 ≤ k ≤ 13, -46 ≤ l ≤ 46; total reflections 203363; independent reflections 16863 (Rint = 0.1223); GOOF = 1.0; R-factor 0.0524]. The predictive analysis for bioavailability criteria has been performed for compound 1 and N-(4-methoxyphenyl)phthalamic acid as well. We have found that the reacting phthalamic acid can be considered as a candidate molecule for further bioscreening whereas compound 1 does not show acceptable physicochemical parameters to be considered as a potentially bioactive molecule.