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- Poly(alkylidenimine) Dendrimers Functionalized with the Organometallic Moiety [Ru(η5-C5H5)(PPh3)2]+ as Promising Drugs Against Cisplatin-Resistant Cancer Cells and Human Mesenchymal Stem CellsPublication . Gouveia, Marisol; Figueira, João; Jardim, Manuel G.; Castro, Rita; Tomás, Helena; Rissanen, Kari; Rodrigues, JoãoHere and for the first time, we show that the organometallic compound [Ru(η5-C5H5)(PPh3)2Cl] (RuCp) has potential to be used as a metallodrug in anticancer therapy, and further present a new approach for the cellular delivery of the [Ru(η5-C5H5)(PPh3)2]+ fragment via coordination on the periphery of low-generation poly(alkylidenimine) dendrimers through nitrile terminal groups. Importantly, both the RuCp and the dendrimers functionalized with [Ru(η5-C5H5)(PPh3)2]+ fragments present remarkable toxicity towards a wide set of cancer cells (Caco-2, MCF-7, CAL-72, and A2780 cells), including cisplatin-resistant human ovarian carcinoma celllines(A2780cisRcells). Also,RuCpandthepreparedmetallodendrimersareactiveagainsthuman mesenchymal stem cells (hMSCs), which are often found in the tumor microenvironment where they seem to play a role in tumor progression and drug resistance.
- cis-Aquabis[bis(diphenylphosphino)ethane-j2P,P000]chlororuthenium(II) hexafluorophosphate dichloromethane sesquisolvate hemihydratePublication . Russo, Luca; Figueira, João; Rodrigues, João; Rissanen, Kari
- Trans-Bis[bis(diphenylphosphino)methane-κ2P,P′]dichlororuthenium(II) dichloromethane disolvate acetone hemisolvate hemihydratePublication . Figueira, João; Rodrigues, João; Rissanen, Kari
- Preparation and characterization of novel poly(alkylidenamine) nitrile ruthenium metallodendrimersPublication . Jardim, Manuel G.; Rissanen, Kari; Rodrigues, JoãoComplete functionalization of N,N,N ,N -[tetrakis(cyanoethyl)hexamethylenediamine] [N C(CH2)2]2N(CH2)6N[(CH2)2C N]2 (4) and N,N,N ,N -[tetrakis(cyanoethoxypropyl)hexamethylenediamine] [N C(CH2)2O(CH2)3]2N(CH2)6N[(CH2)3O(CH2)2C N]2 (7) with the organometallic moiety [Ru(η5C5H5)(PPh3)2Cl] and the five-coordinate cis-[RuCl(dppe)2][PF6] [dppe = 1,2-bis(diphenylphosphanyl)ethane] was attained with good yield, respectively, by treating the metallofragment with the core in methanol (at room temperature and in presence of TlPF6 as a chloride abstractor) and in 1,2 dichloroethane (under reflux). These novel nitrile-functionalized poly(alkylidenamine) dendrimers peripherally functionalized with the ruthenium moieties [Ru(η5-C5H5)(PPh3)2]+ and [RuCl(dppe)2]+ (8–11) were fully characterized by NMR (1H, 13C, 31P), TOF-MS and FTIR. The present results represent a step forward in the knowledge of the most adequate synthetic strategy for total coordination of poly(alkylidenamine) nitrile core derivatives to the different ruthenium complex moieties and confirm the versatility of these systems as building blocks in metallodendrimer chemistry.
- Divergent route to the preparation of hybrid Pt–Fe 2,4,6-Tris(4-ethynyl)phenyl-1,3,5-triazine metallodendrimers for nonlinear opticsPublication . Maiti, Swarup K.; Jardim, Manuel G.; Rodrigues, João; Rissanen, Kari; Campo, Jochen; Wenseleers, WimThe synthesis strategy for the preparation of novel platinum acetylide homometallic and heterobimetallic dendrimers (containing Fe as the other metal fragment) based on a 2,4,6-tris(4-ethynyl)phenyl-1,3,5-triazine core (3) is reported. All the dendrimer generations (G0−G2) were synthesized under copper-free conditions following a divergent route. The G0-Pt dendrimer (4) was synthesized using the 1,3,5-triazine core (3) and cis[Pt(PEt3)2Cl2] with a molar ratio of 1/4. The advantage of the current method is that different dendrimers can be prepared by following the same procedure with only changes in the molar ratios of the reactants involved. For instance, when 3 reacts with 4 in a 4/1 molar ratio, the G1 dendrimer 7 is afforded without the peripheral Pt moiety, but the G1 dendrimer with the peripheral Pt moiety (8) is formed when 3 reacts with 4 in a 1/3 molar ratio. On the other hand, the G2 dendrimer with a peripheral Pt moiety (9) is synthesized when 7 reacts with 4 in a 1/6 molar ratio. The heterobimetallic dendrimers were synthesized up to generation 1 by capping the corresponding Pt dendrimers with the ethynylferrocenyl group (EFC). The respective G0 (6)- and G1-capped (10) dendrimers were synthesized when EFC reacted with 4 and 8 in molar ratios of 9/1 and 18/1, respectively. Nonlinear optical (NLO) polarizabilities measured by hyper-Rayleigh scattering (HRS) have been evaluated for the core 3, for the G0 dendrimer 4, and for the G0 dendrimer capped with EFC (6). In spite of the fact that the stability of the higher generations in chloroform is too low to allow HRS measurements, the reported NLO results show a remarkable enhancement (plus 50%) upon capping the zero dendrimer generation (6), reflecting the importance of the introduction of electron donor organometallic capping groups in the hyperpolarizabilities of the resulting dendrimers.
- cis-Diazido[bis(diphenylphosphino)methane-κ2P,P′]ruthenium(II) dichloromethane 0.42-solvatePublication . Russo, Luca; Nättinen, Kalle; Vertlib, Viatcheslav; Rodrigues, João; Rissanen, Kari
- Three 2,5-dialkoxy-1,4-diethynylbenzene derivativesPublication . Figueira, João; Rodrigues, João; Russo, Luca; Rissanen, Kari2,5-Diethoxy-1,4-bis[(trimethylsilyl)ethynyl]benzene, C(20)H(30)O(2)Si(2), (I), constitutes one of the first structurally characterized examples of a family of compounds, viz. the 2,5-dialkoxy-1,4-bis[(trimethylsilyl)ethynyl]benzene derivatives, used in the preparation of oligo(phenyleneethynylene)s via Pd/Cu-catalysed cross-coupling. 2,5-Diethoxy-1,4-diethynylbenzene, C(14)H(14)O(2), (II), results from protodesilylation of (I). 1,4-Diethynyl-2,5-bis(heptyloxy)benzene, C(24)H(34)O(2), (III), is a long alkyloxy chain analogue of (II). The molecules of compounds (I)-(III) are located on sites with crystallographic inversion symmetry. The large substituents either in the alkynyl group or in the benzene ring have a marked effect on the packing and intermolecular interactions of adjacent molecules. All the compounds exhibit weak intermolecular interactions that are only slightly shorter than the sum of the van der Waals radii of the interacting atoms. Compound (I) displays C-H...pi interactions between the methylene H atoms and the acetylenic C atom. Compound (II) shows pi-pi interactions between the acetylenic C atoms, complemented by C-H...pi interactions between the methyl H atoms and the acetylenic C atoms. Unlike (I) or (II), compound (III) has weak nonclassical hydrogen-bond-type interactions between the acetylenic H atoms and the ether O atoms.
- Syntheses and characterization of novel ruthenium complexes based on 1,3-dicyanobenzenePublication . Csók, Z.; Gandum, C.; Rissanen, K.; Tuzi, A.; Rodrigues, J.
- A convenient route for the preparation of the monohydride catalyst trans-[RuCl(H)(dppe)2] (dppe=Ph2PCH2CH2PPh2): improved synthesis and crystal structurePublication . Figueira, João; Jardim, Manuel G.; Rodrigues, João; Valkonen, Arto; Rissanen, KariA novel and improved room temperature synthesis of the monohydride catalyst trans-[RuCl(H)(dppe)2] complex (1, dppe (1,2-bis(diphenylphosphino)ethane) = Ph2PCH2CH2PPh2) proceeds through oxidation of methanol (the solvent) by the pentacoordinated cis-[RuCl(dppe)2][PF6] complex and t-BuOK as the base is described. Compound 1 was fully characterized by NMR (1H, 13C, 31P), ESI-MS(TOF +), FTIR and elemental analysis. The X-ray structure of 1 was reported for the first time and unambiguously confirms the trans-configuration of the complex.
- 4,4′-[Thiophene-2,5-diylbis(ethyne-2,1-diyl)]dibenzonitrilePublication . Figueira, João; Vertlib, Viatslav; Rodrigues, João; Nättinen, Kalle; Rissanen, KariIn the solid state, the title compound, C(22)H(10)N(2)S, forms centrosymmetric dimers by pairs of non-classical C-H⋯S hydrogen bonds linking approximately coplanar mol-ecules. The benzene ring involved in this inter-action makes a dihedral angle of only 7.21 (16)° with the thio-phene ring, while the other benzene ring is twisted somewhat out of the plane, with a dihedral angle of 39.58 (9)°. The hydrogen-bonded dimers stack on top of each other with an inter-planar spacing of 3.44 Å. C-H⋯N hydrogen bonds link together stacks that run in approximately perpendicular directions. Each mol-ecule thus inter-acts with 12 adjacent mol-ecules, five of them approaching closer than the sum of the van der Waals radii for the relevant atoms. Optimization of the inter-stack contacts contributes to the non-planarity of the mol-ecule.