A Mixed Ligand Platinum(II) Complex: Spectral Analysis, Crystal Structure, Steric Demand of the Ligand, and Bioactivity of cis-[Pt(PPh3)2(L1-O,S)]PF6 (L1-O,S = N,N-Morpholine-N′-benzoylthiourea)

A novel mixed platinum(II) complex with general formula [Pt(PPh3)2(L1-O,S)]PF6 has been synthetized and characterized by elemental analysis, molar conductivity, and by IR and NMR (1H, 13C and 31P) spectroscopic methods. The crystal structure has been determined by single-crystal X-ray crystallography. The molecule presents an almost ideal square-planar geometry, and the crystal is stabilized by weak C?H···O and C?H···F hydrogen bonds, and C?H···π stacking interactions. The steric congestion of ligands is described by ?exact? cone and solid cone angles, and the percentage of metal surface shielded by the ligands. The results are compared to closely related palladium complexes. The X-ray structure revealed the proximity of the ortho phenyl proton of one PPh3 ligand to platinum(II) showing rare intramolecular C?H···Pt anagostic binding interaction. The title complex was determined to be active against tumor cells, and it also showed a moderate inhibitory action against mycobacterium tuberculosis.Fil: Pérez, Hiram. Universidad de La Habana; CubaFil: Ramos, Raúl. Universidad de La Habana; CubaFil: Plutín, Ana M.. Universidad de La Habana; CubaFil: Mocelo, Raúl. Universidad de La Habana; CubaFil: Erben, Mauricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Castellano, Eduardo E.. Universidade de Sao Paulo; BrasilFil: Batista, Alzir A.. Universidade Federal do São Carlos; Brasi

SÍNTESIS, CARACTERIZACIÓN QUÍMICA Y CRISTALOGRÁFICA DE 4-FENIL-6-(4´BROMOFENIL)[2,1-B] IMIDAZOTIAZOL A PARTIR DE 2-AMINO-4-FENILTIAZOL

The synthesis of 4-phenyl-6-(4´bromophenyl)[2,1-b]imidazothiazol (II) from 2-amino-4-phenylthiazol (I) is reported in the present paper. Both compounds were investigated using NMR and IR techniques, as well as x-ray powder diffraction. IR spectral data of compound I show N-H stretching and bending frequencies of the NH2 group (3440 and 3260 cm-1), the aromatic overtone indicating monosubstituted phenyl ring (1605 and 770 cm-1), and the C=N and C-N frequencies of thiazolic ring (1530 and 1280 cm-1). IR spectral data of compound II exhibit characteristic bands (Csp2-H and C=N sym. y asym.) as reported in previous references. 1H-NMR signals of compound I show the thiazolic group proton (7.80 ppm) and those corresponding to compound II characteristic chemical shifts of H2',6' (7.62 ppm) and H3',5' (7.90 ppm) protons of the phenylic group bonded at position 2 of the imidazole ring. 13C-NMR spectral data of the compound II show characteristic C9a, C4a and C8a signals of the imidazole group (174.1, 166.9 and 121.1 ppm) as well as carbon signals of the phenyl group. X-ray diffraction patterns exhibit sharp intensity maxima, which result from the high crystallinity of the two solid phases (low background and no amorphous zone). All patterns were indexed. The cell parameters were determined and refined. Crystals of compound I are tetragonal, a = 12.143 (1), c = 5.771 (2) Å, space group P4/mmm; Crystals of compound II are orthorhombic, a = 12.183 (4), b = 12.150 (10), c = 5.769 (2) Å, space group Pmmm. The structures of these compounds agree with their IR, 1H-NMR and x-ray diffraction spectra.        En este trabajo se reporta la síntesis del 4-fenil-6-(4´bromofenil)[2,1-b]imidazotiazol (II) a partir de 2-amino-4-feniltiazol (I). Se realizó la caracterización química de ambos compuestos mediante las técnicas de IR y RMN, así como la caracterización cristalográfica por DRX mediante la técnica de polvo. En el espectro IR de I se observan las vibraciones de valencia N-H del grupo NH2 (3440 y 3260 cm-1), las de sobretono aromático que indican la monosustitución en el anillo fenílico (1605 y 770 cm-1), y las de los enlaces C=N y C-N del anillo tiazólico (1530 y 1280 cm-1). En el espectro IR de II se observan sus bandas características (Csp2-H y C=N sim. y asim.), en acuerdo con reportes de la literatura. En el espectro RMN-1H de I se observa la señal del protón del grupo tiazólico (7.80 ppm). En el espectro de II se observan los corrimientos químicos característicos de los protones H2',6' (7.62 ppm) y H3',5' (7.90 ppm) del grupo fenilo en la posición 2 del anillo imidazólico. En el espectro RMN-13C de II se observan las señales de los átomos de carbono C9a, C4a y C8a característicos del grupo imidazotiazol (174.1, 166.9 y 121.1 ppm), así como las señales correspondientes a los átomos de carbono del grupo fenilo. Se obtuvieron difractogramas que evidencian una alta cristalinidad de las muestras, Se determinaron y refinaron los parámetros reticulares de la celda unitaria de ambos compuestos. El compuesto I cristalizó en el sistema tetragonal (a = 12.143 (1), c = 5.771 (2) Å, y grupo espacial P4/mmm) y el II en el ortorrómbico (a = 12.183 (4) b = 12.150 (10) c = 5.769 (2) Å, y grupo espacial Pmmm). Esta ligera disminución de la simetría se corresponde con la presencia del átomo de bromo en el anillo bencénico del compuesto II.  &nbsp

On the cytotoxic activity of Pd(II) complexes of N,N-disubstituted-N′-acyl thioureas

The rational design of anticancer drugs is one of the most promising strategies for increasing their cytotoxicity and for minimizing their toxicity. Manipulation of the structure of ligands or of complexes represents a strategy for which is possible to modify the potential mechanismof their action against the cancer cells. Here we present the cytotoxicity of some new palladium complexes and our intention is to show the importance of noncoordinated atoms of the ligands in the cytotoxicity of the complexes. New complexes of palladium (II), with general formulae [Pd(PPh3)2(L)]PF6 or [PdCl(PPh3)(L)], where L = N,N-disubstituted-N′-acyl thioureas, were synthesized and characterized by elemental analysis, molar conductivity, melting points, IR, NMR(1H, 13C and 31P{1H}) spectroscopy. The spectroscopic data are consistent with the complexes containing an O, S chelated ligand. The structures of complexes with N,N-dimethyl-N′-benzoylthiourea, N,N-diphenyl-N′-benzoylthiourea, N,N-diethyl-N′-furoylthiourea, and N,N-diphenyl-N′-furoylthiourea were determined by X-ray crystallography, confirming the coordination of the ligands with the metal through sulfur and oxygen atoms, forming distorted square-planar structures. The N,N-disubstituted-N′-acyl thioureas and their complexes were screened with respect to their antitumor cytotoxicity against DU-145 (human prostate cancer cells), MDA-MB-231 (human breast cancer cells) and their toxicity against the L929 cell line (health cell line from mouse).CAPESCNPqFAPES

SÍNTESIS, CARACTERIZACIÓN QUÍMICA Y CRISTALOGRÁFICA DE TRES N-BENZOILTIOCARBAMATOS

The synthesis of three N-benzoyl-O-alkylthiocarbamates, particularly with ethyl, isobutyl and n-pentyl as alkyl group is reported in the present paper. The three compounds were investigated using NMR and IR techniques, as well as x-ray powder diffraction. IR spectral data show absorption bands of the NH (3208-3269 cm-1 y 1511-1526 cm-1), CO (1696-17805 cm-1), CS (1295-1361 cm-1) groups, and the aromatic ring. The absorption frequencies agree with those reported in previous references for similar compounds. The CO stretching frequency is greater than expected for a secondary amide, due to high electronic delocalization of the fragment [CO-NH-CS-O]. 1H-NMR spectral data show wide signals corresponding to chemical shifts for the proton of NH group (9.22-9.40 ppm), which are a result of the 14N electric cuadrupole effect on the proton. 13C-NMR spectra exhibit signals of CO (162-163 ppm) and CS (189 ppm) groups, which are the most deshielded ones of each spectrum. Thiocarbonilic carbon atom is more deshielded than the carbonilic one, due to the higher average excitation energy of the last one. X-ray diffraction patterns show sharp intensity maxima, which result from the high crystallinity of the three solid phases (low background and no amorphous zone). All patterns were indexed. The cell parameters were determined and refined. Crystals of N-benzoyl-O-ethylthiocarbamate are orthorhombic, a = 11.443 (5), b = 10.035 (4), c = 9.397 (5) Å, space group Pmmm. Crystals of N-benzoyl-O-isobutylthiocarbamate are monoclinic, a = 8.274 (2), b = 17.182 (3), c = 4.884 (1) Å; = 103.93 (4)º, space group P2/m. Crystals of N-benzoyl-O-n-pentylthiocarbamate are monoclinic, a = 8.427 (3), b = 18.055 (6), c = 6.649 (2) Å; = 109.23 (4)º, space group P2/m. The structures of these compounds agree with their IR, 1H-NMR and x-ray diffraction spectra.      En este trabajo se reporta la síntesis de tres N-benzoiltiocarbamatos (de etilo, isobutilo y n-pentilo) así como su caracterización química mediante análisis elemental, y las técnicas de IR y RMN. Además, se realizó la caracterización cristalográfica por DRX mediante la técnica de polvo. En los espectros IR se observan las vibraciones de valencia de los grupos NH (3208-3269 cm-1 y 1511-1526 cm-1), CO (1696-17805 cm-1), CS (1295-1361 cm-1) y del anillo aromático, muy similares a los reportados en la literatura. La del CO es mayor que la esperada para una amida secundaria, debido al alto nivel de delocalización electrónica del fragmento [CO-NH-CS-O]. En los espectros de RMN-1H se observan las señales anchas correspondientes a los corrimientos químicos del protón del grupo NH (9.22-9.40 ppm), lo cual es una consecuencia del efecto que ejerce el cuadrupolo eléctrico del 14N sobre el protón. En los espectros de RMN-13C las señales de los grupos CO (162-163 ppm) y CS (189 ppm) son las más desblindadas. El átomo de carbono tiocarbonílico resulta más desblindado que el carbonílico debido a que éste posee una mayor energía de excitación media. En los patrones de difracción de rayos x se observan máximos de difracción bien definidos, por lo que las tres fases sólidas fueron obtenidas con alta cristalinidad (bajo fondo y ausencia de zonas amorfas en las muestras). Se indexaron los patrones, y se determinaron y se refinaron los parámetros de la celda unitaria. El N-benzoiltiocarbamato de etilo cristaliza en el sistema ortorrómbico (a = 11.443 (5) b = 10.035 (4) c = 9.397 (5) Å, y grupo espacial Pmmm.), y los de isobutilo y n-pentilo en el sistema monoclínico (a = 8.274 (2) b = 17.182 (3) c = 4.884 (1) Å; = 103.93 (4)º, y a = 8.427 (3) b = 18.055 (6) c = 6.649 (2) Å; = 109.23 (4)º respectivamente, y grupo espacial P2/m), en correspondencia con la simetría de dichas moléculas. &nbsp

Synthesis and structural characterization of 1 -(4 methylbenzoyl)-3,3-dimethylthiourea

La estructura cristalina y molecular de la 1-(p-metilbenzoil)-3,3-dimetiltiourea fue determinada por métodos espectroscópicos IR, RMN-'H, "C y difracción de rayos X

Dynamics of Formation of Binuclear Metal Complexes: A New Cu(I) Compound with N-(2-thiophenecarbonyl)-N’-(3-Cl, 4-F-phenyl)thiourea as Ligand

Herein we report the synthesis and characterization of a new copper(I) complex with triphenylphosphine (PPh3) and N-(2-thiophenecarbonyl)-N’-(3-Cl, 4-F-phenyl)thiourea (HL), as ligands. The complex was characterized by vibrational (FTIR and FT-Raman) and multinuclear (1H, 13C {1H}, 31P{1H}) NMR spectroscopies. The crystalline structure of the complex was determined by single-crystal X-ray diffraction, confirming that a neutral binuclear compound, identified as [Cu(PPh3)(L-κ2-N,μ-S)]2, was obtained. The anionic thiourea ligand coordinates to the metal through the sulfur and nitrogen atoms in an unusual bidentate κ2-N,μ-S coordination mode. The complex is a dimer sited on a crystallographic center of symmetry. Each Cu2(μ-S)2 cation bridges trough the sulfur atoms of two symmetry related thiourea moieties and is also coordinated to the nitrogen atom of the thiourea ligand and the phosphorus atom from PPh3 co-ligand, forming a slightly distorted tetrahedral geometry. An intramolecular N−H⋅⋅⋅O=C hydrogen bond is observed in the anionic ligand, forming a six-membered ring that stabilizes the N−H thioamide group. Hirshfeld surface analysis shows that the molecules are connected by weak intermolecular contacts C⋅⋅⋅C, H⋅⋅⋅C and H⋅⋅⋅H which add to the stability of the crystalline packing. The in vitro cytotoxicity study of the complex indicates that it is more active against human lung carcinoma cells (A549), when compared to the free ligand.Fil: Ramos Cairo, Raúl. Universidad de La Habana; CubaFil: María Plutín, Ana. Universidad de La Habana; CubaFil: Oscar Mocelo Castell, Raúl. Universidad de La Habana; CubaFil: Castellano, Eduardo Ernesto. Universidade de Sao Paulo; BrasilFil: Corrêa, Rodrigo S.. Universidade Federal de Ouro Preto; BrasilFil: Nossa González, Diana Lisseth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Erben, Mauricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Regina Cominetti, Marcia. Universidade Federal do São Carlos; BrasilFil: Morais Leite, Celisnolia. Universidade Federal do São Carlos; BrasilFil: Donizeth de Oliveira, Tamires. Universidade Federal do São Carlos; BrasilFil: Batista, Alzir A.. Universidade Federal do São Carlos; Brasi

Ru(II)-based complexes with N-(acyl)-N′,N′-(disubstituted)thiourea ligands : synthesis, characterization, BSA- and DNA-binding studies of new cytotoxic agents against lung and prostate tumour cells.

Four ruthenium(II)-based complexeswith N-(acyl)-N′,N′-(disubstituted)thiourea derivatives (Th)were obtained. The compounds, with the general formula trans-[Ru(PPh3)2(Th)(bipy)]PF6, interact with bovine serum albumin (BSA) and DNA. BSA-binding constants, which were in the range of 3.3–6.5 × 104 M−1, and the thermodynamic parameters (ΔG, ΔH and ΔS), suggest spontaneous interactions with this protein by electrostatic forces due to the positive charge of the complexes. Also, binding constant by spectrophotometric DNA titration (Kb = 0.8–1.8 × 104 M−1) and viscosity studies indicate weak interactions between the complexes and DNA. Cytotoxicity assays against DU-145 (prostate cancer) and A549 (lung cancer) tumour cells revealed that the complexes are more active in tumour cells than in normal (L929) cells, and that they present high cytotoxicity (low IC50 values) compared with the reference metallodrug, cisplatin