Ultrasonic‐assisted synthesis and biological evaluation of a nano‐rod diorganotin phosphonic diamide: Precursor for the fabrication of SnP₂O₇ nano‐structure

Abstract

{L = C 6 H 5 (O)P(NHC 6 H 11 ) 2 } have been synthesized by sonochemical processes at different concentrations without any surfactant or capping agent. The structure and morphology of the prepared complex were investigated by using SEM-EDAX, XRD, DLS, UV-Vis and FT-IR spectroscopy. Nanoparticles with well-defined rod shapes and sizes in the range 30-40 nm have been obtained. Also bulk form of the titled complex was synthesized and characterized by 1 H, 13 C, 31 P, 119 Sn NMR, UV-Vis and FT-IR spectroscopy and compared with its nano-size. The thermal stabilities at bulk and nano-size scale have been studied by thermal gravimetric (TG) and differential thermal analysis (DTA). Further, SnP 2 O 7 nanoparticles were synthesized by direct calcination at 730°C under air atmosphere and characterized using XRD, SEM, and TEM. From XRD measurements, we determined the mean size of the crystallites about 27.4 nm. It is found that the size and morphology of the tin pyrophosphate nano-structures are dependent upon the particles size of precursor compound as well. Two different forms of metal coordination compound (1a, 1b) and the corresponding ligand (L) were screened for their antibacterial activity against the selected Gram-positive and Gramnegative bacteria, showing bactericidal activity for complexes 1a and 1b. In vitro cytotoxicity of compounds was studied against human carcinoma cell lines, A2780 (ovarian cancer) and PC-3 (prostate cancer). Results indicated that 1a and 1b possess relatively strong cytotoxic activity against cancer cells with IC 50 values ranging from 93.2 to 376.2 μM for two exposure time (24 and 48 h).

Nano‐ and micro‐structure tin (IV) complexes bearing 4‐pyridinecarbacylamidophosphate: Sonochemical synthesis, crystal structure, anti‐cholinesterase activity, and docking studies

“…Besides, based on the results reported for tin (IV) complexes, two bands observed around 540-560 and 450-480 cm -1 in C 1 and C 2 are attributed to the Sn-C and Sn-N bonds, respectively. [12,24] The 1 H and 13 C NMR spectral data obtained for the complexes confirm the expected structures of these molecules ( Figure S1-S4). For C 1 , the Sn (IV) satellites with 2 J( 119 Sn, 1 H) and 2 J( 117 Sn, 1 H) coupling constant, 113.55 Hz and 109.56 Hz, respectively, fall in the range for six-coordinate dimethyltin (IV) species.…”

“…The Sn-Cl bond length is 2.547(4) Ǻ which is lying in the normal covalent radii 2.37-2.60 Ǻ [28] and is quite close to reported data in the literature. [13b,29] The Sn-N bond length is 2.357 (12) Ǻ that are shorter than sum of the Vander Waals radii of Sn and N atoms (3.75 Ǻ) [28] and is comparable with the Sn-N distances found in similar complexes of Sn (CH 3 ) 2 Cl 2 and 4-pyridinecarbacylamidophosphates, [13b,24,30] while is longer than Sn-N bond length in other type of organotin (IV) complexes. [31] Also, the Sn-C bond (2.129 (15) Ǻ) is quite close to those reported in the literature [32] and corresponds well to the sum of the covalent radii (2.15 Å) of Sn and C. [33] θ(C8-H8 … O14) = 168 ), which result in graph set motif (III), plus CH … HC contacts to complete the overall supramolecular association.…”

“…[ 11 ] Taking into account the importance finding new tin complexes with biological activity particularly by using biologically potent ligands, in recent years we have become interested in the studies of nano‐tin(IV) complexes with phosphoramide ligands. [ 12 ] Pyridinecarbacylamidophosphates (PCAPh) are phosphoramide derivatives with good pharmacological properties, which can assist in the formation of complexes and provide different coordination modes by O phosphoryl and N pyridine donor sites. [ 13 ] In our previous work, nanoparticles octahedral O ‐ligated 4‐PCAPh‐based tin (IV) complex was synthesized and the cholinesterase inhibitor activity was found.…”

Synthesis, characterization and biological evaluation of a nanorod five‐coordinated Sn(IV) complex. Theoretical studies of (CH3)2Sn(O2PPh2)2

“…Notably, the IC 50 values of a tin–phosphorictriamide complex against some tumour cell lines (Hela, PC‐3, MCF‐7 in the range 99.8–1150 μM) have been reported in the literature, which are higher than the IC 50 values determined in this study of Sn(IV) complexes for the tested cell lines. It can also be seen from Table that compared with ligand L and bulk complex C 1 , the cytotoxicity of nanoscale complex C 2 against A2780 shows a 1.5‐ and 1.3‐fold increase, which is similar to the results of our previously reported nano‐diorganotin complex . Similarly, for the PC‐3 tumour cell line, nanosize C 2 displays lower IC 50 values than free ligand L and bulk form C 1 .…”

“…The synthesis of Ĺ and Ć 1 was reported in our previous paper (Table S1). To determine structure–activity relationships in these compounds, quantum chemical computations (DFT) were performed to obtain the electronic factors including the energies of highest occupied molecular orbital ( E HOMO ) and lowest unoccupied molecular orbital ( E LUMO ), the net atomic charges ( Q ) and the structural descriptors such as dipole moment ( μ ), hydrophobic coefficient (log P ) and molecular volume ( M v ). A comparison between compounds L and Ĺ indicates that their structural difference is only the replacement of a phenyl group in L with a cyclohexylamine group in Ĺ.…”