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The synthesis and structural characterization of three families of coordination complexes synthesized from 4′‐phenyl‐2,2′:6′,2′′‐terpyridine (8, Ph‐TPY), 4′‐(4‐chlorophenyl)‐2,2′:6′,2′′‐terpyridine (9, ClPh‐TPY) and 4′‐(4‐methoxyphenyl)‐2,2′:6′,2′′‐terpyridine (10, MeOPh‐TPY) ligands with the divalent metals Co2+, Fe2+, Mn2+ and Ni2+ are reported. The compounds were synthesized from a 1:2 mixture of the metal and ligand, resulting in a series of complexes with the general formula [M(R‐TPY)2](ClO4)2 (where M = Co2+, Fe2+, Mn2+ and Ni2+, and R‐TPY = Ph‐TPY, ClPh‐TPY and MeOPh‐TPY). The general formula and structural and supramolecular features were determinated by single‐crystal X‐ray diffraction for bis(4′‐phenyl‐2,2′:6′,2′′‐terpyridine)nickel(II) bis(perchlorate), [Ni(C21H15N3)2](ClO4)2 or [Ni(Ph‐TPY)2](ClO4)2, bis[4′‐(4‐methoxyphenyl)‐2,2′:6′,2′′‐terpyridine]manganese(II) bis(perchlorate), [Mn(C22H17N3O)2](ClO4)2 or [Mn(MeOPh‐TPY)2](ClO4)2, and bis(4′‐phenyl‐2,2′:6′,2′′‐terpyridine)manganese(II) bis(perchlorate), [Mn(C21H15N3)2](ClO4)2 or [Mn(Ph‐TPY)2](ClO4)2. In all three cases, the complexes present distorted octahedral coordination polyhedra and the crystal packing is determined mainly by weak C—H...π interactions. All the compounds (except for the Ni derivatives, for which FT–IR, UV–Vis and thermal analysis are reported) were fully characterized by spectroscopic (FT–IR, UV–Vis and NMR spectroscopy) and thermal (TGA–DSC, thermogravimetric analysis–differential scanning calorimetry) methods. [ABSTRACT FROM AUTHOR]

The chemical reaction of 4-bromo-benzoyl-chloride and 2-amino-thia-zole in the presence of potassium thio-cyanate yielded a white solid formulated as C15H10BrN3OS2, which consists of 4-bromo-benzamido and 2-benzo-thia-zolyl moieties connected by a thio-urea group. The 4-bromo-benzamido and 2-benzo-thia-zolyl moieties are in a trans conformtion (sometimes also called s-trans due to the single bond) with respect to the N-C bond. The dihedral angle between the mean planes of the 4-bromo-phenyl and the 2-benzo-thia-zolyl units is 10.45 (11)°. The thio-urea moiety, -C-NH-C(=S) -NH- fragment forms a dihedral angle of 8.64 (12)° with the 4-bromo-phenyl ring and is almost coplanar with the 2-benzo-thia-zolyl moiety, with a dihedral angle of 1.94 (11)°. The mol-ecular structure is stabilized by intra-molecular N-H⋯O hydrogen bonds, resulting in the formation of an S(6) ring. In the crystal, pairs of adjacent mol-ecules inter-act via inter-molecular hydrogen bonds of type C-H⋯N, C-H⋯S and N-H⋯S, resulting in mol-ecular layers parallel to the ac plane. [ABSTRACT FROM AUTHOR]

The synthesis and XRD characterization at 295 K of three isomers, X-fluoro-N-(2-hydroxy-5-methyl phenyl) benzamide: (o-FPhB), (m-FPhB), and (p-FPhB), are presented. o-FPhB and m-FPhB show high structural affinity concerning molecular and packing structures. The planarity of the C1-C7(O1)-N1-C8 peptide bond in o-FPhB, and m-FPhB confers high stability, favoring its tendency to acquire a resonant structure in the peptide segment and in the molecule. For p-FPhB, a stereochemical gate opens, leading to the activation of N-H∙∙∙∙O interpeptide bonds, defining its supramolecular properties. Active participation of the halogen in the assembly of the structures is observed, forming intramolecular rings and molecule chains during crystal growth. The o-FPhB and m-FPhB form parallel sheets that develop hydrogen C-H···Cg, halogen C-F···Cg, or C=O···Cg interactions. Theoretical evaluations of the properties performed by the DFT/B3LYP/(6-311G(d,p) showed good agreement with the experimental values. The IR analysis reaffirms the presence of N-H, C=O, O-H, C-F, and C-H. In the UV-Vis, an increase in the energetic stability, O···H interactions, and electrostatic potential in the NH region reaffirm the disposition of p-FPhB for the formation of the N-H···O interpeptide bond. A molecular docking on the benzamides involving protein receptors showed similar behavior for all three isomers. [ABSTRACT FROM AUTHOR]

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Two novel bicomponent solid forms of mebendazole (MBZ) were developed as a means to modulate its psychochemical and pharmaceutical properties. Supramolecular synthesis of MBZ A or C with perchloric or methyl sulfuric acids yields two salts of 1 : 1 stoichiometry, which were analyzed through single crystal X-ray diffraction. MBZ perchlorate crystallizes in the P21/n space group, while MBZ methyl sulfate crystallizes in the P1¯ space group. The API and its counterions are interconnected in both crystal packings by an R 22 (8) supramolecular motif. The 3-dimensional crystal structure is also stabilized by other strong intermolecular hydrogen bonds as well as non-classical interactions. FT-IR spectra are consistent with the inclusion of the anions in the crystal structure. MBZ perchlorate is stable up to 210 °C when it undergoes endothermic loss of the ester moiety. MBZ methyl sulfate is stable up to 160 °C when endothermic elimination of the methylcarbamate moiety occurs. The solubility behavior of MBZ perchlorate, studied by UV-visible spectroscopy, suggests an improvement by a factor of seven with respect to MBZ A, in the apparent solubility of MBZ in 0.1 mol L−1 HCl. Further experiments are required to evaluate both the stability of the solids and the maximum solubility of the API. [ABSTRACT FROM AUTHOR]

The aim of the present study was to report the crystal structure and spectroscopic, electronic, supramolecular and electrostatic properties of a new polymorph of 4‐(pyridin‐2‐yl)pyrimidin‐2‐amine (C9H8N4). The compound was synthesized under microwave irradiation. The single‐crystal X‐ray structure analysis revealed an angle of 13.36 (8)° between the planes of the rings, as well as molecules linked by Nsp2—H...N hydrogen bonds forming dimers along the crystal. The material was analyzed by FT–IR vibrational spectroscopy, while a computational approach was used to elucidate the vibrational frequency couplings. The existence of Nsp2—H...N hydrogen bonds in the crystal was confirmed spectroscopically by the IR peaks from the N—H stretching vibration shifting to lower wavenumbers in the solid state relative to those in the gas phase. The supramolecular studies confirmed the formation of centrosymmetric R22(8) rings, which correspond to the formation of dimers that stack parallel to the b direction. Other weak C—H...π interactions, essential for crystal growth, were found. The UV–Vis spectroscopic analysis showed a donor–acceptor process, where the amino group acts as a donor and the pyridine and pyrimidine rings act as acceptors. The reactive sites of the molecule were identified and their quantitative values were defined using the electrostatic potential model proposed in the multifunctional wave function analyzer multiwfn. The calculated interaction energies between pairs of molecules were used to visualize the electrostatic terms as the leading factors against the dispersion factors in the crystal‐growth process. The docking results showed that the amino group of the pyrimidine moiety was simultaneously anchored by hydrogen‐bonding interactions with the Asp427 and His407 protein residues. This compound could be key for the realization of a series of syntheses of molecules that could be used as possible inhibitors of chronic myelogenous leukemia. [ABSTRACT FROM AUTHOR]

Two novel multicomponent crystal forms of the prodrug 5-fluorocytosine (5-FC), an ionic cocrystal and a monohydrate salt, with 2,4,6-trinitrophenol (picric acid, PA) and 3,5-dinitrosalicylic acid (DNSA), respectively, were rationally designed and synthesized. Nitro compounds are used to treat many diseases, such as cancer, one of the 5-FC targets via gene-directed prodrug therapy. In addition, within the wide range of applications for nitro compounds is the formation of charge-transfer complexes with organic molecules. Among all 5-FC crystalline structures depicted, only two contain nitro compounds: a salt with PA and a dihydrate cocrystal with 5-nitrouracil. Therefore, the two new single translucent pale gold prism crystals of 5FC-PA and 5FC-DNSA were successfully obtained by slow evaporation from aqueous solution and characterized by X-ray diffraction (single crystal and powder), Fourier Transform Infrared (FT-IR), and Raman (FT-Raman) spectroscopies. In both crystal structures, the 5-FC pyrimidine ring is protonated at the N3 atom and the respective packings are mainly stabilized by N–H⋯O H-bonds. For the 5FC-PA ionic cocrystal, the formation of triple H-bonds (two N–H⋯O and one charge assisted N–H+⋯N H-bonds) among the 5-FC molecules was observed. This is consistent with the expected stability of the duplex structure, which is considered the strongest association between two species. In addition to the structural study, Hirshfeld surface analysis was carried out based on the single crystal X-ray diffraction data. Thermal stability was assessed through thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and hot-stage microscopy (HSM), indicating that these compounds are stable up to approximately 200 °C. The results contribute to the diversity of new 5-FC solid forms and introduce two novel compounds, with possible application in fungal/cancer medicine formulations or to better understand the behavior of cytosine in DNA/RNA base pairing. [ABSTRACT FROM AUTHOR]

Two CuII complexes [Cu(C14H13N4O2)Cl]n, I, and [Cu4(C8H10NO2)4Cl4]n, II, have been synthesized. In the structure of the mononuclear complex I, each ligand is coordinated to two metal centers. The basal plane around the CuII cation is formed by one chloride anion, one oxygen atom, one imino and one pyridine nitro­gen atom. The apical position of the distorted square-pyramidal geometry is occupied by a pyridine nitro­gen atom from a neighbouring unit, leading to infinite one-dimensional polymeric chains along the b-axis direction. Each chain is connected to adjacent chains by inter­molecular C—HO and C—HCl inter­actions, leading to a three-dimensional network structure. The tetra­nuclear complex II lies about a crystallographic inversion centre and has one core in which two CuII metal centers are mutually inter­connected via two enolato oxygen atoms while the other two CuII cations are linked by a chloride anion and an enolato oxygen. An open-cube structure is generated in which the two open-cube units, with seven vertices each, share a side composed of two CuII ions bridged by two enolato oxygen atoms acting in a μ3-mode. The CuII atoms in each of the two CuO3NCl units are connected by one μ2-O and two μ3-O atoms from deprotonated hydroxyl groups and one chloride anion to the three other CuII centres. Each of the penta­coordinated CuII cations has a distorted NO3Cl square-pyramidal environment. The CuII atoms in each of the two CuO2NCl2 units are connected by μ2-O and μ3-O atoms from deprotonated alcohol hy­droxy groups and one chloride anion to two other CuII ions. Each of the penta­coordinated CuII cations has a distorted NO2Cl2 square-pyramidal environment. In the crystal, a series of intra­molecular C—H···O and C—H···Cl hydrogen bonds are observed in each tetra­nuclear monomeric unit, which is connected to four tetra­nuclear monomeric units by inter­molecular C—H···O hydrogen bonds, thus forming a planar two-dimensional structure in the (1...01) plane. [ABSTRACT FROM AUTHOR]

The 2-hydrazino­pyridine precursor has been widely used to prepare ligands of various kinds by condensation with carbonyl compounds. These types of ligands are suitable for synthesizing novel transition metal (II) complexes with inter­esting magnetic properties. In this context we have synthesized the ligand 1-(2-hy­droxy­phenyl-2-ethyl­idene)-2-(pyridin-2-yl)hydrazine (HL) which was used in the preparation of the mononuclear title complex, [Ni(C13H12N3O)(C13H13N3O)]NO3·0.5H2O. As a result of the presence of HL and L in the [{Ni(HL)(L)}]+ unit, the complex appears to be a supramolecular dimer composed of the Δ(−) and Λ(−) optical isomers, which are linked by strong hydrogen-bonds. As well as the dimer generated by two mononuclear [{Ni(HL)(L)}]+ cations, the asymmetric unit also contains two nitrate anions and one water mol­ecule. Each Ni atom is coordinated to two ligand mol­ecules by a nitro­gen atom of the pyridine ring, an imine nitro­gen atom and a phenolic oxygen atom of one of the ligand mol­ecules and a phenolate oxygen atom of the other organic mol­ecules. The environment around the cation is a distorted octa­hedron. The basal planes are defined by the two nitro­gen atoms of the pyridine rings and the two phenolic oxygen atoms of the ligand, the apical positions being occupied by the azomethine atoms. The O atoms of one of the nitrate ions are disordered over two sets of sites in a 0.745 (9):0.255 (9) ratio. In the crystal, the dimers are linked by numerous hydrogen bonds, forming a three-dimensional framework. [ABSTRACT FROM AUTHOR]

This manuscript addresses the synthesis, structural characterization and optical properties of a 1D coordination polymer (CPs) and 2D and 3D Metal–Organic Frameworks (MOFs) obtained from lanthanide metals, 3-hydroxinaftalene-2,7-disulfonic acid (3-OHNDS) and two different phenanthroline derivates as ancillary ligands. The first is a family of 2D compounds with formula [Ln(3-OHNDS)(H2O)2], where Ln = La(1), Pr(2), Nd(3) and Sm(4). The addition of 1,10-phenanthroline (phen) in the reaction produces 1D compounds with general formula [Ln(3-OHNDS)(phen)(H2O)]·3H2O, where Ln = La(5), Pr(6), Nd(7) and Sm(8). Finally, the synthesis with 3,4,7,8-tetramethyl-1,10-phenanthroline (3,4,7,8-TMPhen) as an ancillary ligand results in the formation of the 3D [La(3-OHNDS)(3,4,7,8-TMphen)(H2O)] (9) compound. The photoluminescence (PL) properties of 1D and 2D compounds were fully investigated in comparison with the 3-OHNDS ligand. One of the most important results was the obtaining of a white-light single-emitter without adding dopant atoms in the structure. With all these results in mind it was possible to establish structure–property relationships. [ABSTRACT FROM AUTHOR]

Crystal engineering of the anti-HIV drug lamivudine has currently provided improvement in its pharmaceutical performance besides getting insights into several branches of nucleoside structural chemistry. Here, we demonstrated the synthon robustness and the role of the five-membered ring conformation in the diversity of lamivudine crystal forms even with supramolecular isomerism. Oxathiolane conformation defines the ability of lamivudine to assemble into different multicomponent molecular crystal forms. This was observed in a polymorph of lamivudine hydrochloride, which is related to the previously reported lamivudine hydrochloride monohydrate. The absence of water molecules has little effect on their supramolecular organization. If water is not present, just one conformational change from C3′-endo puckering in the monohydrate form to the C2′-endo one in the anhydrate form reported here is enough to cause a hydrogen bonding reorganization involving the 5′-OH group. DFT calculations reveal a low energy gap for this change in the oxathiolane conformation. Therefore, lamivudine can variably forward its 5′-OH group through changing oxathiolane conformations of similar energies. In addition, the isostructurality and robustness of the supramolecular synthons were illustrated in two halide salts of lamivudine with hydrobromic and hydrofluoric acids. While the previously reported lamivudine hydrochloride is strictly isostructural to the hydrobromide salt, the lamivudine hydrofluoride crystallized as a hydrofluoric acid cocrystal. HF cocrystallization appears to be primarily related to further stabilization between sheets rather than a major size effect. [ABSTRACT FROM AUTHOR]

Starting from easily prepared (cyclobutylsulfonyl)benzene ( 1), a stereoselective synthesis of (±)-grandisol, accomplished in nine steps, with an overall yield of ca. 18 %, has been presented by Monteiro and Stefani (Eur J Org Chem 14:2659-2663, ). Most of the synthetic intermediates were secured in good to excellent yields as crystalline compounds requiring no or minimal purification, should being amenable to scale up. The structures and absolute stereochemistry of ( 2), ( 3), ( 4a), ( 5), ( 8) and ( 9) were established by IR and NMR (H, C) spectroscopies and confirmed by X-ray diffraction analysis. Compound ( 2) crystallizes in orthorhombic Pbca, a = 16.0565(5), b = 9.5144(6), c = 23.9728(7) Å, the ( 3) crystallizes in monoclinic P2/ c, a = 5.6390(5), b = 17.8630(16), c = 12.8678(12) Å and β = 111.928(7)°, the ( 4a) crystallizes in monoclinic P2/ c, a = 5.7002(9) Å, b = 17.2752(14) Å, c = 14.9168(9) Å and β = 109.464(8)°. The other three cyclobutylsulfonyl derivatives crystallize in the same monoclinic space group P2/ c with cell parameters ( 5) a = 8.072(4), b = 11.486(9), c = 14.565(8) Å and β = 101.373(4)°, ( 8) a = 11.3448(2), b = 7.9377(1), c = 18.5329(4) Å and β = 94.147(1)° and ( 9) a = 37.7571(9), b = 11.4434(3), c = 8.1824(2) Å and β = 90.748(1)°. Graphical Abstract: X-ray crystal structures of six synthetic intermediates prepared from the stereoselective synthesis of (±)-grandisol.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The roméite-group is part of the pyrochlore-supergroup and comprises cubic oxides of A2B2X6Y formula in which Sb5+ predominates in the B-site. The A and Y main occupants determine different minerals in the group and are important for the discovery of new mineral species. Two different roméite-group mineral samples were analysed by electron microprobe analysis (EMPA), Raman spectroscopy and single-crystal X-ray diffraction (XRD). The first sample is from Prabornaz Mine (locality of the original roméite), Saint Marcel, Valle d'Aosta, Italy, whereas the other one occurs in Kalugeri Hill, Babuna Valley, Jakupica Mountains, Nezilovo, Veles, Macedonia. Sample 1 was identified as fluorcalcioroméite, and sample 2 as hydroxycalcioroméite. Both samples belong to the cubic crystal system, space group Fd 3 ¯ m, Z = 8, where a = 10.2881(13) Å, V = 1088.9(4) Å3 for sample 1, and a = 10.2970(13) Å, V = 1091.8(4) Å3 for sample 2. The crystal structure refinements converged to (1) R1 = 0.016, wR2 = 0.042; and (2) R1 = 0.023, wR2 = 0.049. Bond-valence calculations validated the crystal structure refinements determining the correct valences at each crystallographic site. Discrepancies observed in the Sb5+ bond-valence calculations were solved with the use of the proper bond valence parameters. The resulting structural formulas are (Ca1.29Na0.55□0.11Pb0.05)Σ=2.00(Sb1.71Ti0.29)Σ=2.00[O5.73(OH)0.27]Σ=6.00[F0.77O0.21(OH)0.02]Σ=1.00 for sample 1, and (Ca1.30Ce0.51□0.19)Σ=2.00(Sb1.08Ti0.92)Σ=2.00O6.00[(OH)0.61O0.21F0.18]Σ=1.00 for sample 2. The Raman spectra of the samples exhibited the characteristic bands of roméite-group minerals, the most evident corresponding to the Sb-O stretching at around 510 cm−1. [ABSTRACT FROM AUTHOR]

Menezesite, ideally Ba2MgZr4(BaNb12O42)·12H2O, occurs as a vug mineral in the contact zone between dolomite carbonatite and "jacupirangite" (=a pyroxenite) at the Jacupiranga mine, in Cajati county, São Paulo state, Brazil, associated with dolomite, calcite, magnetite, clinohumite, phlogopite, ancylite-(Ce), strontianite, pyrite, and tochilinite. This is also the type locality for quintinite-2H. The mineral forms rhombododecahedra up to 1 mm, isolated or in aggregates. Menezesite is transparent and displays a vitreous luster; it is reddish brown with a white streak. It is non-fluorescent. Mohs hardness is about 4. Calculated density derived from the empirical formula is 4.181 g/cm³. It is isotropic, nmeas > 1.93(1) (white light); ncalc = 2.034. Menezesite exhibits weak anomalous birefringence. The empirical formula is (Ba1.47K0.53Ca0.31Ce0.17Nd0.10Na0.06La0.02)Σ2.66(Mg0.94Mn0. 23Fe0.23Al0.03)Σ1.43(Zr2.75Ti0.96Th0.29)Σ4.00 [(Ba0.72Th0.26U0.02)Σ1.00(Nb9.23Ti2.29Ta0.36Si0.12)Σ12.00O42]·12H2O. The mineral is cubic, space group Im0̄３ (204), a = 13.017(1) Å, V = 2206(1) ų, Z = 2. Menezesite is isostructural with the synthetic compound Mg7[MgW12O42](OH)4·8H2O. The mineral was named in honor of Luiz Alberto Dias Menezes Filho (born 1950), mining engineer, mineral collector and merchant. Both the description and the name were approved by the CNMMN-IMA (Nomenclature Proposal 2005-023). Menezesite is the first natural heteropolyniobate. Heteropolyanions have been employed in a range of applications that include virus-binding inorganic drugs (including the AIDs virus), homogeneous and heterogeneous catalysts, electro-optic and electrochromic materials, metal and protein binding, and as building blocks for nanostructuring of materials. [ABSTRACT FROM AUTHOR]

Abstract: The solid state properties of deflazacort (1-(1β,16α)-21-(acetyloxy)-11-hydroxy-2′-methyl-5′H-pregna-1,4-dieno[17,16-d]oxazole-3,20-dione, 1) were investigated using differential scanning calorimetry (DSC), thermogravimetry (TG), single-crystal X-ray diffraction, solid and liquid nuclear magnetic resonance spectroscopy (13C NMR), Fourier transform infrared and Raman spectroscopy (FTIR and FT Raman). From the trends observed in the crystal structure and spectral data some conclusions can be made about hydrogen bonding, molecular conformation and crystal packing. Compound 1 crystallizes in an orthorhombic cell, space group P212121 and the following lattice parameters: a =11.2300(5), b =12.8161(8), c =16.171(1)Å, V: 2327.4(2)Å3, D c: 1.260g/cm3, R1=0.0479, =0.1012. The crystal structure is stabilized by intra and intermolecular interactions, which provides for a very closely packed form. The NMR data indicated that 1 shows a similar conformation in solid and liquid state; while, thermal data revealed that 1 follows a monophasic pattern with a DSC melting peak at 258.4°C (ΔH 99.7Jg−1, n =3), indicating that 1 is thermally stable as solid; but, as liquid is unstable to undergo a thermal decomposition reaction. The reactivity of 1 toward light and moisture was examined via DSC and TLC. The data indicated that 1 do not interact with water to give hydrated forms or decomposition products; however, light degrades 1. [Copyright &y& Elsevier]

The ruthenium(II) compounds cis -[Ru(bpy) 2 (4-bzpy)(CO)](PF 6 ) 2 ( I ) and cis -[Ru(bpy) 2 (4-bzpy)(Cl)](PF 6 ) ( II ) (4-bzpy = 4-benzoylpyridine, bpy = 2,2′-bipyridine) were synthesized and characterized by spectroscopic and electrochemical techniques. The crystal structure of II was determined by X-ray diffraction. The photochemical behavior of I in aqueous solution shows that irradiation with ultraviolet light (365 nm) releases both CO and 4-bzpy leading to the formation of the cis -[Ru(bpy) 2 (H 2 O) 2 ] 2 + ion as identified by NMR and electronic spectroscopy. Carbon monoxide release was confirmed with the myoglobin method and by gas chromatographic analysis of the headspace. CO release was not observed when aqueous I was irradiated with blue light (453 nm). Changes in the electronic and 1 H NMR spectra indicate that I undergoes photoaquation of 4-bzpy to form cis -[Ru(bpy) 2 (CO)(H 2 O)] 2 + . Blue light irradiation of aqueous II released the coordinated 4-bzpy to give the cis -[Ru(bpy) 2 (H 2 O)(Cl)] 2 + ion. When the latter reaction was carried out in the presence of the nucleobase guanine, Ru-guanine adducts were formed, indicating that the metal containing photoproduct may also participate in biologically relevant reactions. The photochemical behavior of I indicates that it can release either CO or 4-bzpy depending on the wavelength chosen, a feature that may have therapeutic application. [ABSTRACT FROM AUTHOR]

Matioliite, ideally NaMgAl5(PO4)4 (OH) 6·2H2O, occurs as a secondary hydrothermal mineral in the Gentil mine granite pegmatite, Mendes Pimentel Co., Minas Gerais, Brazil. Some crystals are zoned to more Fe-rich compositions with an Fe2+:Mg ratio of approximately 1:1, corresponding to an intermediate member of the burangaite-matioliite solid-solution series. Matioliite is intimately associated with fluorapatite, crandallite, and zoned gormanite-souzalite cystals. The mineral forms prismatic to tabular crystals, up to 1 mm long. Matioliite is transparent and displays a vitreous luster; it is blue to colorless with a white streak. It is non-fluorescent. Mohs hardness is about 5. Calculated density is 2.948 g/cm³. Matioliite is biaxial negative, ηα = 1.597(2), ηβ = 1.627(2), ηγ = 1.632(1) (white light), 2V (meas.) = 43(2)°, 2V (calc.) = 44°, dispersion r > v, orientation X = b, Z ∧ c = 6°. Pleochroism is Y > X > Z, X = light blue to colorless, Y = blue, Z = colorless. The empirical formula is (Na0.94Ca0.01)∑0.95 (Mg0.88Fe0.112+Mn0.01)∑1.00(Al4.84Fe0.133+)∑4.97 (PO4)4.03(OH)5.76·2H2O. The mineral is monoclinic, space group C2/c, a = 25.075(1) Å, b = 5.0470(3) Å, c = 13.4370(7) Å, β = 110.97(3)°, V = 1587.9(4) ų, Z = 4. Crystal-structure determination was carried out and showed it is isostructural with burangaite, dufrénite, and natrodufrénite. Both the description and the name were approved by the CNMMN-IMA (Nomenclature Proposal 2005-011). The "magnesium analog of burangaite" described from the Gold Quarry mine, Carlin-trend, Eureka County, Nevada; "burangaite" from Hochgosch, Millstätter See-Rücken, Kärnten, Austria; and "burangaite" described from Córrego Pomarolli, Linópolis, Divino das Laranjeiras, Minas Gerais, Brazil, are probably matioliite. [ABSTRACT FROM AUTHOR]

Famotidine ( FMT), a histamine H2-receptor antagonist, is a drug commonly used in treatments of gastroesophageal diseases that presents solid-state polymorphism ( A and B forms), the marketed form being the metastable polymorph B. A new stable salt was obtained by combination of FMT and maleic acid as coformer. FMT maleate ( FMT- MLT) was prepared either by solvent evaporation or comilling methods. Single-crystal X-ray diffraction reveals that ( FMT)+ in FMT- MLT adopts an extended conformation that is stabilized by classical and nonclassical H-bonds. The three-dimensional packing consists of tapes along the axis b that further develop a columnar array based on H-bonds involving ( FMT)+ side chain. Nonconventional π-stacking interactions between adjacent tapes were also identified. Fourier transform infrared, differential scanning calorimetry, thermogravimetric analysis, polarized light thermal microscopy, and scanning electron microscopy were employed to characterize the multicomponent complex. According to the solubility values in water and simulated gastric fluid, FMT- MLT exhibits such a performance that improves on the solubility of the commercially available polymorph. Finally, the higher stability of FMT- MLT regarding both FMT forms, as well as its easy preparation from either A or B forms or a mixture of them, also allows to consider this salt as a valuable alternative to avoid the polymorphism issue in marketed formulations containing FMT. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:3754-3763, 2014 [ABSTRACT FROM AUTHOR]

Highlights: [•] New polymorph of the 9,10-dichloroanthracene is reported. [•] Halogen contacts define the packing motif of the crystal structure of the new polymorph. [•] DFT-D and MP2 calculations estimates properly the intermolecular interactions present in the system. [Copyright &y& Elsevier]

A DNA-like duplex of nucleosides is probable to exist even without the 5′-phosphate groups needed to assemble the chain backbone. However, double-stranded helical structures of nucleosides are unknown. Here, we report a duplex of nucleoside analogs that is spontaneously assembled due to stacking of the neutral and protonated molecules of lamivudine, a nucleoside reverse transcriptase inhibitor (NTRI) widely used in anti-HIV drug combinatory medication. The left-handed lamivudine duplex has features similar to those of i-motif DNA, as the face-to-face base stacking and the helix rise per base pair. Furthermore, the protonation pattern on alternate bases expected for a DNA-like duplex stabilized by pairing of neutral and protonated cytosine fragments was observed for the first time in the lamivudine double-stranded helix. This structure demonstrates that hydrogen bonds can substitute for covalent phosphodiester linkage in the stabilization of the duplex backbone. This interesting example of spontaneous molecular self-organization indicates that the 5′-phosphate group could not be a requirement for duplex assembly. Helical stacking of the hydrogen-bonded 3TC−3TC+ pairs gives rise to lamivudine duplex. This structure reveals that nucleosides have the least structural requisites to self-assemble DNA duplexes. [ABSTRACT FROM AUTHOR]

Mebendazole (MBZ) is a common benzimidazole anthelmintic that exists in three different polymorphic forms, A, B, and C. Polymorph C is the pharmaceutically preferred form due to its adequated aqueous solubility. No single crystal structure determinations depicting the nature of the crystal packing and molecular conformation and geometry have been performed on this compound. The crystal structure of mebendazole form C is resolved for the first time. Mebendazole form C crystallizes in the triclinic centrosymmetric space group and this drug is practically planar, since the least-squares methyl benzimidazolylcarbamate plane is much fitted on the forming atoms. However, the benzoyl group is twisted by 31(1)° from the benzimidazole ring, likewise the torsional angle between the benzene and carbonyl moieties is 27(1)°. The formerly described bends and other interesting intramolecular geometry features were viewed as consequence of the intermolecular contacts occurring within mebendazole C structure. Among these features, a conjugation decreasing through the imine nitrogen atom of the benzimidazole core and a further resonance path crossing the carbamate one were described. At last, the X-ray powder diffractogram of a form C rich mebendazole mixture was overlaid to the calculated one with the mebendazole crystal structure. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:2336–2344, 2009 [ABSTRACT FROM AUTHOR]

Abstract In the present work, the crystal structure of (3b)-3-acetoxy-30-methoxy-30-oxo-olean-12-en-28-oic acid, (Spergulagenic Acid A) is presented. The compound was isolated from Cecropia telenitida roots, employing semi-pilot scale extraction system and automated flash chromatography device. Vapor diffusion of methanol in chloroform yield suitable crystals for X-ray diffraction. The crystal packing of the Spergulagenic Acid A as methanol solvate is formed by strong hydrogen bonds between the SA-A molecule and the methanol. SA-A as well other pentacyclic triterpenes, present interesting potential biological activities. Inasmuch as biological activity is clearly related to molecular structure, the main goal of the present work was the structural elucidation of this molecule by single crystal X-ray diffraction. To the best of our knowledge, there is no previous crystal structure report in the literature for the titled compound or any other with simultaneous substitution at C 2 and C 7. Graphical abstract Image 1 Highlights • Isolation at semi-pilot scale of Spergulagenic Acid A, a pentacyclic triterpene from roots of an endemic Colombian plant. • Several automated flash chromatography procedures were employed in order to guarantee the isolation reproducibility. • First crystal structure of Spergulagenic Acid A is reported. This structure have simultaneous substitution at C 17 and C 20. [ABSTRACT FROM AUTHOR]

In this paper three novel salts of the anti-tuberculosis drug Isoniazid (INH) with the GRAS salt formers (oxalic, maleic and methanesulfonic acids) were supramolecularly synthesized by solvent evaporation method. Aiming to expand the diversity of supramolecular synthons of this drug as well as obtaining new solid forms with enhanced solubility and thermal stability, these salts namely oxalate (INH−OXA), maleate (INH−MAL) and mesylate (INH−MES) were fully characterized by X-ray diffraction (SCXRD, PXRD), spectroscopic (FT-IR) and thermal (TGA, DSC, HSM) techniques. At the same time, salts' solubility was explored. Analysis of the crystal structures and packings were analyzed in details, showing that the INH salts exhibit layered structures stabilized by N H⋯O, C H⋯O and π···π interactions. The salt formations were confirmed from the FT-IR and FT-Raman spectra and their thermal behaviors indicate that INH−OXA and INH−MES are thermally more stable than the corresponding INH. The equilibrium solubilities of these salts, in different buffered media, were evaluated and both INH−MAL and INH−MES were found to be more soluble (∼3 fold) than INH. Therefore, the present study proved that salt formation is an efficient strategy to enhance solubility and thermal stability of INH. [ABSTRACT FROM AUTHOR]

5-Fluorocytosine (5-FC) has been widely used for the treatment of fungal infections and recently was found to exert an extraordinary antineoplastic activity in gene directed prodrug therapy. However, despite of its intense use, 5-FC exhibits tabletability issues due its physical instability in humid environments, leading to transition from the anhydrous to monohydrate phase. By considering that salt formation is an interesting strategy to overcome this problem, in this paper crystal engineering approach was applied to the supramolecular synthesis of new 5-FC salts with sulfuric, hydrobromic and methanesulfonic inorganic acids. A total of four structures were obtained, namely 5-FC sulfate monohydrate (1:1:1), 5-FC hydrogen sulfate (1:1), 5-FC mesylate (1:1) and 5-FC hydrobromide (1:1), the last one being a polymorphic form of a structure already reported in the literature. These novel salts were structurally characterized by single crystal X-ray diffraction and its supramolecular organization were analyses by Hirshfeld surface analysis. The vibrational behavior was evaluated by Raman spectroscopy and it was found to be consistent with the crystal structures. [ABSTRACT FROM AUTHOR]

Hexafluorosilicate salts of the antidepressant drugs Paroxetine (PRX) and Fluoxetine (FLX), [PRX] 2 SiF 6 and [FLX] 2 SiF 6 ⋅H 2 O, are investigated herein by SCXRD, Hirshfeld surface analysis, and Infrared spectroscopy. By their crystal structures, it is possible to observe, for the first time, at least at the best of our knowledge, the formation of a supramolecular architecture of the [SiF 6 ] 2− anion with protonated secondary amine groups. The [PRX] 2 SiF 6 crystallizes in the P2 1 space group and the [FLX]2SiF 6 ⋅H 2 O in the P2 1 /c , as a hydrate racemate. While two conformers are present in the asymmetric unit of [PRX] 2 SiF 6 , two enantiomers enclose the one of [FLX] 2 SiF 6 ⋅H 2 O. Analysis of the crystal packing show that N HF Si (1.94–2.42 Ǻ), C HF Si (2.36–2.62 Å), and C Hπ interactions are the main contributors toward the supramolecular architectures in these salts. [ABSTRACT FROM AUTHOR]

Rifampicin is a semi-synthetic drug derived from rifamycin B, and currently integrates the fixed dose combination tablet formulations used in the treatment of tuberculosis. It is also used in the leprosy polychemotherapy and prophylaxis, which are diseases classified as neglected according to the World Health Organization. Rifampicin is a polymorphic drug and its desirable polymorphic form is labeled as II, being the main goal of this study the elucidation of its crystalline structure. Polymorph II is characterized by two molecules with different conformations in the asymmetric unit and the following lattice parameters: a = 14.0760 (10) Å, b = 17.5450 (10) Å, c = 17.5270 (10) Å, β = 92.15°. Differently to the previously reported structures, a charge transference from the hydroxyl group of the naphthoquinone of one conformer to the nitrogen of the piperazine group of the second conformer was observed. The relevance of the knowledge of this crystalline structure, which is the preferred polymorph for pharmaceutical formulations, was evidenced by analyzing raw materials with polymorphic mixtures. Thus, the results presented in this contribution close an old information gap allowing the complete solid-state characterization of rifampicin. [ABSTRACT FROM AUTHOR]

In this paper, the influence of pseudohalide ligands coordinated to the ruthenium center on the hydrogenation of cyclohexene was investigated. The pseudohalide complexes containing ruthenium were synthesized from the cis -[RuCl 2 (dppb)(N-N)] { where N-N = 2,2′-bipyridine (bipy) (1A) , 4,4′-dimethyl-2,2′-bipyridine (Me-bipy) (2) , or 4,4′-dimethoxy-2,2′-bipyridine (MeO-bipy) (3) , dppb = 1,4-bis(diphenylphosphino)butane}, by chloride exchange to provide complexes with general formula cis -[RuL 2 (dppb)(N-N)] {where L 2 = N 3 − (4) , (7) and (9) CN − (5) , (8) and (10) or SCN − (6) and (11) }. All complexes were characterized using spectroscopic, electrochemical techniques, as well as elemental analyses to check their molecular formulation and purity. Furthermore, crystal structure of the complexes cis -[Ru(N 3 ) 2 (dppb)(bipy)] ( 4 ), cis -[Ru(CN) 2 (dppb)(bipy)] ( 5 ), cis -[Ru(SCN) 2 (dppb)(bipy)] ( 6 ), cis -[Ru(CN) 2 (dppb)(Me-bipy)] ( 8 ), and cis -[Ru(SCN) 2 (dppb)(MeO-bipy)] ( 11 ) were determined by single-crystal X-ray diffraction, as well as the X-ray structure of the solvate complex [RuCl(CH 3 CN)(dppb)(bipy)](PF 6 ) ( 1B ). Dichloride and pseudohalide complexes containing ruthenium were applied as pre-catalysts in the hydrogenation of cyclohexene, after pre-established conditions using the cis -[RuCl 2 (dppb)(bipy)] (1A) as a target complex. The quantitative conversion of cyclohexene to cyclohexane was obtained in 5 h at 25 °C using 0.1 mol% of (1A) in methanol solution at 15 atm H 2 . The substituted bipy derivatives (2) and (3) were also effective pre-catalysts, but pseudohalides were not under these conditions. [ABSTRACT FROM AUTHOR]

Four new complexes of the general formula: (Ph 4 P) 2 [Sn(CH 3 ) 2 (RSO 2 N CS 2 ) 2 ], where Ph 4 P = tetraphenylphosphonium cation and R = CH 3 , ( 1 ), CH 3 CH 2 ( 2 ), C 6 H 5 ( 3 ), 4-FC 6 H 4 ( 4 ), were prepared by the reaction of the appropriate potassium N -R-sulfonyldithiocarbimates, K 2 (RSO 2 N CS 2 ), and tetraphenylphosphonium chloride with dimethyltin dichloride. The compounds 1 – 4 were characterized by 1 H, 13 C and 119 Sn NMR, 119 Sn Mössbauer, vibrational spectroscopy and by elemental analyses of C, H, N and Sn. The crystal structure of 1 was determined by X-ray diffraction techniques. The in vitro antifungal activity of the tin(IV) complexes were evaluated against the fungi Rhizoctonia solani and Botrytis cinerea by the Poisoned food test. The new compounds showed comparable activities to the fungicides manzate and ziram. [ABSTRACT FROM AUTHOR]

In the present work, the synthesis, characterization, antifungal activity, molecular docking study and in silico approach of five thiosemicarbazone derivatives and their corresponding zinc(II) complexes are described. The compounds were characterized by elemental analysis, IR, UV–Vis and NMR spectroscopic measurements, molar conductivity measurements, emission spectra, high-resolution mass spectrometry and X ray study. The antifungal activity of the free ligands and synthesized compounds was preliminarily evaluated against Candida albicans (ATCC 90028), Candida tropicalis (ATCC 13803) and Candida glabrata (ATCC 2001), by the minimum inhibitory concentration (MIC) assay. Two complexes, 4 (MIC = 3.18 to 6.37 μM) and 5 (MIC = 25.95 μM for all) showed promising results, being highly active against all strains evaluated. The X-ray analyses shown that the complex 2 crystallizes in the centrosymmetric space group P 2 1 /c of the monoclinic system and the coordination sphere around zinc(II) atom is better described as slightly distorted octahedral. The Hirshfeld surface (HS) analysis showed that non-classical H···H and C···H/H···C contacts contribute with 65.9% while the S···H and N···H (21%) and Cl···H and O···H interactions (12%) complete the HS area. The molecular docking results, performed against CYP51 enzyme (sterol 14α-demethylase) of C. albicans and C. glabrata shows that the complexes 4 (ΔG = −10.75 and − 12.90 kcal/ mol) and 5 (ΔG = −11.12 and − 14.53 kcal/ mol) showed the highest binding free energies of all compounds. The ADME-Tox (absorption, distribution, metabolism, excretion and toxicity) in silico parameters evaluated showed promising results for all compounds. [Display omitted] • Three new Zinc(II) complexes are synthesized and characterized. • Antifungal activity of free ligands and complexes were tested against Candida spp. • The molecular docking suggests strong interactions of the most active compound with CYP51 enzyme. • In silico ADMET showed a promising pharmacokinetic profile of Zn(II) complexes. [ABSTRACT FROM AUTHOR]

Samples of efavirenz (EFZ) were evaluated to investigate the influence of the micronization process on EFZ stability. A combination of X-ray diffraction, thermal analysis, FTIR, observations of isotropic chemical shifts of ¹H in distinct solvents, their temperature dependence and spin-lattice relaxation time constants (T1), solution (1D and 2D) 13C nuclear magnetic resonance (NMR), and solid-state 13C NMR (CPMAS NMR) provides valuable structural information and structural elucidation of micronized EFZ and heptane-recrystallized polymorphs (EFZ/HEPT). This study revealed that the micronization process did not affect the EFZ crystalline structure. It was observed that the structure of EFZ/HEPT is in the same form as that obtained from ethyl acetate/hexane, as shown in the literature. A comparison of the solid-state NMR spectra revealed discrepancies regarding the assignments of some carbons published in the literature that have been resolved. [ABSTRACT FROM AUTHOR]

Isobenzofuran-1( 3H )-ones (phtalides) are heterocycles that present a benzene ring fused to a γ-lactone functionality. This structural motif is found in several natural and synthetic compounds that present relevant biological activities. In the present investigation, the 3-(2-hydroxy-4,4-dimethyl-6-oxocyclohexen-1-yl)isobenzofuran-1( 3H )-one was characterized by single-crystal X-ray analysis. In the crystal structure, there are two molecules per asymmetric unit. One of them exhibits resonance assisted hydrogen bonds (RAHBs). Semi-empirical and DFT calculations were performed to obtain electronic structure and π-delocalization parameters, in order to better understand the energy stabilization of RAHBs in the crystal packing of the studied molecule. The structural parameters showed good agreement between theoretical and experimental data. The theoretical investigation revealed that the RAHBs stabilization energy is directly related to the electronic delocalization of the enol form fragment. In addition, RAHBs significantly affected the HOMO and charge distribution around the conjugated system. [ABSTRACT FROM AUTHOR]

Four nickel(II) complexes of general formula [Ni(RSO 2 N CS 2 ) (PPh 3 ) 2 ] where R = CH 3 ( 2a ), CH 3 CH 2 ( 2b ), CH 3 (CH 2 ) 3 ( 2c ) and CH 3 (CH 2 ) 7 ( 2d ) and PPh 3 = triphenylphosphine; and two nickel(II) complexes of general formula [Ni(RSO 2 N CS 2 )dppe] where R = CH 3 (CH 2 ) 3 ( 3c ) and CH 3 (CH 2 ) 7 ( 3d ) and dppe = 1,2-bis(diphenylphosphine)ethane) were prepared. These new complexes were obtained by the reaction of nickel(II) chloride hexahydrate with potassium N -alkylsulfonyldithiocarbimates and the appropriate phosphine using ethanol/water as solvent. The IR, UV–Vis and 1 H, 13 C and 31 P NMR spectra, elemental analysis of Ni and the HR-ESI-MS were consistent with the formation of square planar nickel(II) complexes with mixed ligands. The structures of the compounds 2b and 2c were determined by single crystal X-ray diffraction. The compounds are isostructural and crystallize in the space group P 1 ¯ of the triclinic system. The activities of the complexes were investigated in vitro against Botrytis cinerea , Colletotrichum acutatum and Alternaria solani , fungi species that affect various commercially important plants. All the complexes were active. [ABSTRACT FROM AUTHOR]

For active pharmaceutical ingredients (API) in the solid state, the occurrence of hydration/dehydration phase transitions may have implications upon the efficiency of the pharmaceutical product, once they are often accompanied by changes of physicochemical properties. Thus, it is important for pharmaceutical research and development to investigate these mechanisms based on the crystal structures of the API. In this work, beyond the structural characterization of a new salt of the antidepressant drug Paroxetine [an HBr hemihydrate, (PRX+Br-)·0.5H2O], by single crystal X-ray diffraction (SXRD), thermal analysis (DSC/TGA), and hot stage microscopy (HSM), we were able to perform a complete investigation toward the reversible hydration/dehydration solid phase transitions occurring for this salt. In addition, solubility measurements for the anhydrous and hemihydrate solid forms of the new salt are compared with those of its isostructural hydrochloride hemihydrate salt, (PRX+Cl-)·0.5H2O, for which hydration/dehydration processes are still not completely understood due to structure instability after dehydration. [ABSTRACT FROM AUTHOR]

Botrytis blight is a very destructive disease caused by Botrytis spp., infecting flowers, trees, vegetables and fruits. Twelve new compounds were prepared by the reaction of potassium N -aryl-sulfonyldithiocarbimates with Morita-Baylis-Hillman derivatives bearing phenyl and furyl groups. These are the first examples of allyldithiocarbimate anions and were isolated as tetraphenylphosphonium salts. The new compounds were characterized by HRMS, NMR and Infrared spectroscopy. Further, the structures of three allyldithiocarbimates were determined by single crystal X-ray diffraction. The compounds are isostructural and crystallize in the space group P2 1 /c of the monoclinic system, and the allyldithiocarbimate anions present Z configuration. All the compounds were active against Botrytis cinerea . The best results were achieved with the tetraphenylphosphonium ( Z )-3-(furan-2-yl)-2-(methoxycarbonyl)allyl-(4-chlorophenylsulfonyl)dithiocarbimate (IC 50 38 μM). [ABSTRACT FROM AUTHOR]

Complexes with the general formula [Ru(dppb)(R) 2 ] {where: dppb = 1,4-bis(diphenylphosphino)butane and R = piperidinedithiocarbamate (pipeCS 2 − ) ( 1 ); morpholinedithiocarbamate (morphCS 2 − ) ( 2 ); ethilenodiaminedithiocarbamate (ethCS 2 − ) ( 3 ) and hexamethilenominedithiocarbamate (hexCS 2 − ) ( 4 )} were synthesised from [RuCl 2 (dppb)] 2 -μ-(dppb). The complexes were characterised by nuclear magnetic resonance of phosphorus ( 31 P{ 1 H} NMR), cyclic voltammetry (CV) as well as elemental analyses. The X-ray structures of ( 1 ), ( 2 ), and ( 3 ) were determined and are presented here. Additionally, the complexes ( 1 – 4 ) were used as pre-catalysts in the epoxidation of cyclooctene, and initial results show that complex ( 4 ) has a selectivity of 74% in the epoxide product, with 53% conversion. The epoxidation catalysed used iodosylbenzene (PhIO) as primary oxidant. [ABSTRACT FROM AUTHOR]

This work reports on the synthesis and characterization of new complexes of the type [Cu(O–O)(N–N)X], where O–O = 4,4,4-trifluoro-1-phenyl-1,3-butanedione (HBTA), 1-(4-chlorophenyl)-4,4,4-trifluoro-1,3-butanedione (HBTACl) or 2-thenoyltrifluoroacetone (HTTA); N–N = 2,2-bipyridine (Bipy) or 1,10-phenanthroline (Phen) and X = NO 3 − or ClO 4 − . These complexes were characterized by elemental analyses, conductivity measurements, FT-IR, UV–Vis, EPR, High-resolution Electrospray Ionization Mass Spectrometry (HRESIMS) and TG/DTA. The X-ray structural analysis of two representative compounds indicates that the geometry around the copper ion is distorted square-pyramidal and it is coordinated to β-diketone via the oxygen atoms and to N -donor heterocyclic ligands via its two nitrogen atoms. A perchlorate or nitrate ion weakly bonded occupies the apical position, completing the coordination sphere. The crystal packing is stabilized by non-classical hydrogen bonds and weak interactions π–π stacking. The cytotoxic activity of compounds was investigated in a chronic myelogenous leukemia cell line. The complexes with 1,10-phenanthroline are more active than carboplatin. As example, the compound [Cu(BTACl)(Phen)NO 3 ] inhibits the growth of K562 cells with an IC 50 value equal to 2.1 μM. [ABSTRACT FROM AUTHOR]

Abstract: The complexes [RuCl(SpymMe2-N,S)2(NO)] (1) and [Ru(dppb)(SpymMe2-N,S)2] (2) (dppb=1,4-bis(diphenylphosphino)butane, SpymMe2 =deprotonated 4,6-dimethyl-2-mercaptopyrimidine) were obtained and characterized by elemental analysis, spectroscopic techniques including X-ray crystallography, conductimetry and cyclic voltammetry. Energy Decomposition Analysis (EDA) calculation indicated strong intermolecular interaction between monomers of complex 1, as suggested by the 1H NMR spectrum of this complex, in chloroform solution. Additionally, preliminary tests were carried out, in order to evaluate the cytotoxicity activity on cancer cell lines of the new complexes, and the free ligands, against MDA-MB-231 (breast cancer), Hela (cervical cancer), U251 (glioma cancer) tumor cell lines and the V79 (Chinese lung fibroblast hamster) cell line. The best result was obtained for the complex 1 with IC50 value of 0.11±0.02, against MDA-MB-231 tumor cells. [Copyright &y& Elsevier]

5-Fluorocytosine(5-FC) was crystallized with complementary dicarboxylicacids, aiming to achieve a controlled synthesis of structures basedon the ΔpKarule proposed in thesalt–cocrystal continuum study and to provide structural informationhelpful in the comprehension of its supramolecularity. Although 5-FCtends to be basic, pKa= 3.26, only threesalts are reported. In this way, new 5-FC salts were obtained, thefumaric, maleic and oxalic ones, all crystallizing in the monoclinicspace group P21/c. Inthe 5-FC oxalate and fumarate cases, the acid molecules are placedon an inversion center in a fashion that each half molecule exhibitsone terminal donor–acceptor site, leading to the constitutionof a 5-FC–acid–5-FC heterodimer. Such a heterodimeris observed in only one donor–acceptor site of the maleateof 5-FC, whose acid molecule exhibits a closed chain architecture.Infrared and Raman spectra recorded for the three compounds complementthe salt characterization on the basis of the extent of proton transfer.Thermal analysis evidence that the salt formation decreases the meltingpoint of the new compounds, ranking this molecule as a coformer candidateto improve the physical properties of other drugs. [ABSTRACT FROM AUTHOR]

Mebendazole mesylate monohydrate, a new stable salt of mebendazole ( MBZ), has been synthesized and fully characterized. It was obtained from recrystallization of MBZ forms A, B, or C in diverse solvents with the addition of methyl sulfonic acid solution. The crystal packing is first organized as a two-dimensional array consisting of rows of alternating MBZ molecules linked to columns of mesylate ions by hydrogen bonds. The three-dimensional structure is further developed by classical intermolecular interactions involving water molecules. In addition, nonclassical contacts are also found. The vibrational behavior is consistent with the crystal structure, the most important functional groups showing shifts to lower or higher frequencies in relation to the MBZ polymorphs. Thermal analysis indicates that the compound is stable up to 50° C. Decomposition occurs in five steps. Solubility studies show that the title compound presents a significant higher performance than polymorph C. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:3528-3538, 2013 [ABSTRACT FROM AUTHOR]

Highlights: [•] The cytosine hydrobromide (CytHBr) salt was obtained. [•] X-ray diffraction, FT-IR and thermal analysis were performed. [•] Intermolecular contacts were explored by Hirshfeld Surface and fingerprint plots. [•] Br−⋯π, π⋯π and N H⋯Br− interactions stabilize the crystal self-assembly. [•] DSC thermal analysis was followed by Hot Stage Optical Microscopy. [ABSTRACT FROM AUTHOR]