Bio-based synthesis of Nano-Ceria and evaluation of its bio-distribution and biological properties.

Bio-based synthesis of Nano-Ceria (NC) was performed in Linum usitatissimum L. (Lu) seeds extract as capping agent. Obtained gel was calcined at 400, 500, and 600 °C to investigate the effect of temperature on the size and morphology of the particles. All samples had spherical morphology which their crystallite size was decreased in higher temperature. Products were characterized by TGA/DTA, UV-vis, FESEM, FTIR and XRD. The band gap of the prepared samples was calculated through Tauc plot in the range of 3.2-3.4 eV. The results of MTT assay confirmed that NC has been shown no significant toxicity on A549 cell line. 2',7'-dichlorofluorescin diacetate (DCFDA) was used to determine antioxidant properties of NC on A549 cell and the results showed that all concentrations of NC could reduce reactive oxygen species (ROS). NC was labeled with technetium (99mTc) for in vivo bio-distribution study in Wistar rat. Radiolabeled NC was stable in different environments of PBS buffer and human serum with radiochemical purity of more than 95% according to the instant thin layer chromatography (ITLC) method. DLS analysis showed radiolabeled particles had small size and pleasant colloidal stability. Bio-distribution of radiolabeled NC illustrated the highest accumulation in kidneys (1 h: 5.94 ±â€¯0.77%ID/g, 4 h: 10.95 ±â€¯5.99%ID/g, 24 h 7.94 ±â€¯0.36%ID/g). Moreover, low uptake of 99mTc-NC in stomach confirmed the in vivo stability of 99mTc-NC. Accordingly, NC could be a worthy candidate for biological purposes and in vivo studies.

Hirshfeld surface analysis of new phosphoramidates.

Hirshfeld surfaces and two-dimensional fingerprint plots are used to visualize and analyze intermolecular interactions in six new phosphoramidate structures, [2,6-F2-C6H3C(O)NH]P(O)[X]2 {X = N(C2H5)2 (1), [X]2 = NHCH2C(CH3)2CH2NH and with one CH3OH solvated molecule (2)}, [C6H5O]2P(O)Y [Y = NC4H8O (3), NHC6H4(3-Br) (4)] and [Z]2P(O)OP(O)[Z]2 [Z = N(CH3)(CH2C6H5) (5), NHC6H4(4-CH3) (6)]. Study of the short intermolecular contacts in structures (1)-(6) by Hirshfeld surfaces demonstrate that the O atom of P=O is a better H-atom acceptor than the O atom of C=O for (1) and (2), and also relative to the O atom of the C6H5O group for (3) and (4), and relative to the bridge O atom of the P(O)OP(O) segment for (5) and (6). The results confirm that the crystal packing is related to the kind of substituent linked to the P atom. Compounds (1), (2), (4) and (6), with characteristic N-H···O hydrogen bonds, show a pair of intense spikes (including the intermolecular H···O contacts) in the fingerprint plots, summarizing the major features of each structure in the related two-dimensional plot. For (3) and (5), without any N-H unit, the two short spikes are observed for (3) but are absent for (5). The upper d(e) and d(i) values (distances to the Hirshfeld surfaces for the nearest atoms outside and inside) in the fingerprint plots are more compact in (3) than in (4), and in (5) than in (6), reflecting the more efficient packing in (3) and (5). The tertiary N atoms of (3) and (5) do not take part in any intermolecular contacts involving H atoms. Moreover, structures (3)-(6) show greater contribution from C···H contacts relative to O···H contacts. Finally, Hirshfeld surfaces and fingerprint plots are employed for a comparison of the two independent molecules in the asymmetric unit of (1) and also, for a comparison of (6), in the orthorhombic crystal system, with the previously reported monoclinic polymorph (Pourayoubi, Fadaei et al., 2012).

N,N'-Dibenzyl-N,N'-dimethyl-N''-(p-tol-yl)phospho-ric triamide.

The asymmetric unit of the title compound, C(23)H(28)N(3)OP, contains two independent mol-ecules with significant conformational differences. For example, the torsion angles N-C-C-C involving the N-benzyl moieties are 57.3 (7) and 11.6 (8)° in one mol-ecule and 76.5 (7) and 97.4 (7)° in the other. In each mol-ecule, the P atom exhibits a distorted tetra-hedral conformation [the bond angles at P are in the ranges 104.7 (2)-115.2 (2) and 105.1 (2)-115.1 (2)° in the two molecules], and the phosphoryl group and the N-H group adopt an anti orientation with respect to one another. In the crystal, mol-ecules are linked via N-H⋯O(P) hydrogen bonds, forming a chain parallel to the a axis.

N,N'-Di-tert-butyl-N''-(2-chloro-acet-yl)phospho-ric triamide.

The P atom in the title mol-ecule, C(10)H(23)ClN(3)O(2)P, has a distorted tetra-hedral coordination. In the C(O)NHP(O) unit, which has syn-oriented phosphoryl and N-H groups, the P-N bond of 1.703 (2) Šis longer and the O-P-N angle of 103.86 (7)° is contracted compared with the respective values in the two P(O)NHC(CH(3))(3) units [P-N = 1.632 (2) and 1.624 (2) Å; O-P-N = 116.80 (8) and 115.32 (8)°]. In the crystal, each mol-ecule is hydrogen bonded to two adjacent mol-ecules via N-H⋯O hydrogen bonds, forming a linear sequence of alternating R(2) (2)(8) and R(2) (2)(12)/R(2) (1)(6)-fused rings along [010]. The O atom of the carbonyl group acts as a double H-atom acceptor.