Synthesis, Crystal Structure and Antitumor Activities of a New Cobalt-containing Tungstoantimonate Na₉[{Na(H₂O)₂}₃{Co(H₂O)}₃(α-B-SbW₉O₃₃)₂]·28H₂O

Cation-Directed Synthetic Strategy Using 4f Tungstoantimonates as Nonlacunary Precursors for the Generation of 3d–4f Clusters

“…As for the KCoLnSbW 9 compounds, the addition of CoCl 2 to the reaction mixture instantaneously led to a pink solution, indicating the presence of octahedrally coordinated Co II centers, whereas blue reaction solutions were observed at temperatures higher than 80 °C, which could be explained by the formation of square-pyramidally coordinated Co II metal centers, as present in the Herve-type sandwich POT. 17 Initial crystallization attempts upon slow evaporation of the reaction mixture in a pure NaOAc buffer resulted in three different crystal phases consisting of the desired 3d−4f cluster KTMLnSbW 9 , unreacted 4f precursor, and the corresponding Krebs POM Na 10 [(TM(H 2 O) 3 ) 2 (WO 2 ) 2 (SbW 9 O 33 ) 2 ] (TM = Co II , Ni II ). 18 Regarding the 3:1 stoichiometric ratio of TM to 4f precursor, 1 equiv of TM was grafted onto the 3d−4f compound, whereas 2 equiv led to the formation of Na 10 [(TM(H 2 O) 3 ) 2 (WO 2 ) 2 (SbW 9 O 33 ) 2 ], leaving the unreacted 4f precursor to crystallize (Figure S17).…”

Antifungal activity of silver salts of Keggin-type heteropolyacids against Sporothrix spp.

“…The structures of POMs may or may not contain heteroatoms, which divides this class of compounds into two groups: (1) the isopolianions of the formula (MmOy) xand (2) heteropolyanions of the formula (XnMmOy) x- [11]. Biologically, POMs inhibit the replication of various nonretro RNA and DNA viruses and tumor cells and act synergistically when combined with antibiotics against methicillin and vancomycin-resistant Staphylococcus aureus [12,13]. Keggin-type heteropolyacids (HPAs) are molecules formed by a central tetrahedron XO 4 , where X may be chosen among any element with the ability for tetrahedral coordination, and usually silicon (Si) or phosphorus (P) are the preferred choice [13].…”

“…Biologically, POMs inhibit the replication of various nonretro RNA and DNA viruses and tumor cells and act synergistically when combined with antibiotics against methicillin and vancomycin-resistant Staphylococcus aureus [12,13]. Keggin-type heteropolyacids (HPAs) are molecules formed by a central tetrahedron XO 4 , where X may be chosen among any element with the ability for tetrahedral coordination, and usually silicon (Si) or phosphorus (P) are the preferred choice [13]. Several Keggin-type HPA salts containing the cations Na + , Fe 3+ , K + , Ce 3+ , and Ba 2+ showed activity against viruses and bacteria [15].…”

Tetra-cobalt-substiituted Dimeric Tungstoantimonate: Na10[Co4(H2O)10(B- -SbW9O33)2]�36H2O

“…This should be attributed to the synergism and enhancement effect of transition metals on the properties of POMs, especially the POMs of containing cobalts [12,13]. Therefore, substituting of multiple transition metals may be an effective way to tune properties of POMs for developing functional materials.…”

“…Therefore, a multiple lacunary precursor obtained easily with a high stability in a relativity large pH range is crucial. Thus, the synthesis of compound 1 not only enriches the POMs family, but also possesses certain potential value for the synersim and enhancement effect of multiple cobalts on the properties of POMs, particularly, the enhancement of antitumor activities [13].…”