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Research has been conducted on the crystal engineering. The role of crystal engineering in understanding the intermolecular interactions and supramolecular and solid state chemistry is discussed.

The synthesis of four new enneanuclear Mn/Ce clusters containing the [[Ce.sup.IV][Mn.sup.III.sub.8][O.sub.8]](12+) core which comprises a saddlelike loop with a central [Ce.sup.IV] ion is reported. The results revealed these complexes as new structural types of single-molecule magnets (SMMs) whose intermolecular interactions are mediated by hydrogen-bonding interactions with lattice-water molecules of crystallization.

The employment of the anion of 2,6-diacetylpyridine dioxime (dapdo[H.sub.2]) as a pentadentate chelate in transition metal cluster chemistry is described. The studies have shown the ligating flexibility of pyridyl-dioxime chelates and their usefulness in the synthesis of new polynuclear [Mn.sub.x] clusters without needing the co-presence of carboxylate ligands.

Single-molecule magnets (SMMs) represent a molecular approach to nanoscale magnetic materials. A template-based procedure that cleanly converts a Mn(super III) chain polymer to a molecular loop complex, a prototype of a valuable new potential methodology for accessing loop species with Mn and other metals is discovered.

Based on structures identified from a high throughput (HT) crystallization cocrystals of itraconazole possessing diverse physical properties are engineered. The solubility and dissolution properties of cocrystals could be similar to those of the amorphous compound and superior to the crystalline pure phase, thus presenting opportunities to increase bioavailability even in cases where stable, crystalline salt forms cannot be found.

Supramolecular synthesis, the self-assembly of pre-selected molecular components represents a typical example of generation of nanoscale structures from readily available molecular moieties. It is observed that more than one structure results from the assembly of similar components and these complexities are studied.

Background: The Cancer Genome Atlas analysis revealed that somatic EGFR, receptor tyrosine-protein kinase erbB-2 (ERBB2), Erb-B2 receptor tyrosine kinase 3 (ERBB3) and Erb-B2 receptor tyrosine kinase 4 (ERBB4) gene mutations (ERBB family mutations) occur alone or co-occur with somatic mutations in the gene encoding the phosphatidylinositol 3-kinase (PI3K) catalytic subunit (PIK3CA) in 19% of human epidermal growth factor receptor 2 (HER2)-positive breast cancers. Because ERBB family mutations can activate the PI3K/AKT pathway and likely have similar canonical signalling effects to PI3K pathway mutations, we investigated their combined impact on response to neoadjuvant HER2-targeted therapies.Methods: Baseline tumour biopsies were available from 74 patients with HER2-positive breast cancer who were enrolled in the phase II TCHL neoadjuvant study (ICORG 10-05) assessing TCH (docetaxel, carboplatin, trastuzumab) (n = 38) versus TCL (docetaxel, carboplatin, lapatinib) (n = 10) versus TCHL (docetaxel, carboplatin, trastuzumab, lapatinib) (n = 40), each for six cycles. Activating mutations in PIK3CA and ERBB family genes were identified using mass spectrometry-based genotyping. Phosphatase and tensin homolog (PTEN) expression was assessed by immunohistochemistry.Results: PIK3CA and/or ERBB family mutations were detected in 23 (31.1%) tumour samples tested, whereas PTEN expression was low in 31.1% of cases tested. Mutation frequency was similar in each treatment arm (31.3% in TCH arm, 30% in TCL arm and 31.3% in TCHL arm) and was not influenced by oestrogen receptor (ER) status (27.6% in ER-negative patients, 33.3% in ER-positive patients) or progesterone receptor (PR) status (32.6% in PR-negative patients, 29% in PR-positive patients). There was no significant difference in pathological complete response (pCR) rates between 47 patients with wild-type (WT) tumours and 22 patients whose tumours carried mutations (in either PIK3CA or ERBB family genes) (42.5% vs. 54.5%; p = 0.439). Similarly, there was no significant difference in pCR rates between patients with PIK3CA/ERBB family mutated/PTEN-low (i.e., PI3K-activated) tumours and patients without PI3K activation (50% vs. 44%; p = 0.769). However, in the TCHL (but not the TCH) group, the pCR rate was higher for 9 patients with PIK3CA/ERBB family mutated tumours than for 20 patients with PIK3CA/ERBB family WT tumours (77.8% vs. 35%; p = 0.05).Conclusions: Our results indicate that patients who receive neoadjuvant TCHL and have PIK3CA/ERBB family mutated tumours may be more likely to have a pCR than patients with WT tumours.Trial Registration: ClinicalTrials.gov, NCT01485926 . Registered on 2 December 2011. [ABSTRACT FROM AUTHOR]

The first example of a 2D network exhibiting periodic tiling patterns with three-connected and four-connected nodes.

Background. To assess the temporal patterns of late gastrointestinal (GI) and genitourinary (GU) radiotherapy toxicity and resolution rates in a randomised controlled trial (All-Ireland Cooperative Oncology Research Group 97-01) assessing duration of neo-adjuvant (NA) hormone therapy for localised prostate cancer. Material and methods. Node negative patients with > 1 of: PSA > 20 ng/mL, Gleason score ≥ 7, and stage T3 or more, were included. Follow-up, including toxicity assessment, was three-monthly in the early stages and yearly thereafter. Results. Median follow-up from the end of RT was 6.8 years. In the interval between 90 days following the end of RT and the last toxicity assessment, GI and GU toxicity (any grade) was found in 50% and 51% of 240 and 241 patients, respectively. For those who did develop toxicity, the median time from end of RT until the first development of any grade GI or GU toxicity was 1.2 years and 1.6 years, respectively, whilst median time to final resolution was 1.6 years and 2.2 years, respectively. Grade 2 (G2) or greater GI and GU toxicity occurred in 29 (12.1%) and 40 (16.6%) patients, respectively. The proportion with unresolved G2 + GI and GU toxicity was 89% and 79%, respectively, in year 1, 69% and 65% in year 2, 59% and 52% in year 3 and 27% and 32% in year 5. Conclusion. Long-term toxicities continue to occur many years after NA hormone therapy and RT. The rate of occurrence does not appear to reduce within the time frame during which our patients were followed. The percentage of patients suffering from G2 + toxicity at any time is however low. Resolution of these toxicities continues for the duration of the follow-up. [ABSTRACT FROM AUTHOR]

Three new tetranuclear complexes [MnIII2CoIII2O2(L)2][ClO4]2 ( 1), [MnIII2FeIII2O2(L)2][ClO4]2 ( 2), and [MnIII2MnIII2O2(L)2][MnII(NCS)4] ( 3) have been synthesized through reactions of the mononuclear [MnIIIL] precursor with the corresponding metal perchlorate under aerobic conditions [H3L = tris(2-salicylaldimine)amine, a condensation product between tris(2-aminoethyl)amine and salicylaldehyde in a 1:3 molar ratio]. These compounds have been characterized by spectroscopic and analytical techniques including single-crystal X-ray structure analysis, electron paramagnetic resonance (EPR) spectroscopy, Mössbauer spectroscopy, and magnetic measurements. The structure of 1 consists of oxo-/phenoxo-bridged CoIII and MnIII centers in a defective double-cubane topology. The molecules of 2 and 3 have similar structures with the CoIII centers changed to FeIII centers in 2 and to MnIII centers in 3. These isostructural complexes have been scrutinized with regard to changes in distortions (distances and angles) of the metal coordination spheres. Magnetic studies indicate that 1, 2, and 3 show predominant antiferromagnetic interactions. Changes in the electronic properties concomitant with changes in the distortions in 1, 2, and 3 are analyzed in terms of magnetostructural correlations. [ABSTRACT FROM AUTHOR]

The article provides some insights into the implications of the Clinical Trials Directive (CTD) of the European Union on European clinical research. The directive was initially designed to increase clinical trial patient protection, and prior to the implementation of CTD, there was European-wide acknowledgment of and adherence to the principles of good clinical practice in clinical research. CTD has reduced the enthusiasm and commitment of middle-ground investigators in research projects.

Illustrates the periodic tiling of a two-dimensional structure having three- and four-connected nodes. Incorporation of 3 equiv of hexamethylenetetramine (HMTA) with 5 equiv of Cu[sub 2](mu-O[sub 2]CCH[sub 2]CH[sub 3])[sub 4]; Effect of stoichiometry of the reactants on HMTA coordination into desired environment.

Two new binuclear nickel(II) complexes [Ni2L2(NCS)2](ClO4)2 (1) and [Ni2L2(NCO)2](ClO4)2 (2), where L is a pentadentate Schiff base ligand derived from the reaction of 2 mol of 2-benzoyl pyridine and 1 mol of diethylene triamine, have been prepared and characterized. The structures of complexes 1 and 2 have been studied by single crystal X-ray diffraction analysis. The structure analysis reveals that each nickel(II) center is coordinated in a distorted octahedral (NiN6) fashion consisting of three nitrogen atoms from one and two nitrogen atoms from other pentadentate ligand and the last one from terminal thiocyanato/cyanato ion. The variable temperature magnetic susceptibility of both compounds 1 and 2 have been studied and found a very weak magnetic interaction between two nickel(II) centers consistent with the structures (Ni⋯Ni distance of 5.809(1) A˚ for 1 and 5.695(1) A˚ for 2 with no suitable bridge or linkage to propagate magnetic interaction). [Copyright &y& Elsevier]

The article presents a template synthesis and discusses single-molecule magnets. Single-molecule magnets (SMM) represent a molecular approach to nanoscale magnetic materials. A SMM derives its properties from a combination of a large ground-state spin value and an Ising type of magnetoanisotropy. Several types of SMM are now known, most of them containing manganese[SUPIII], but there is continuing need for novel structural types to enlarge the available database and thus improve understanding of this interesting phenomenon.

Abstract: Six novel metal–organic complex assemblies constructed from a conformation-flexible ligand – pyridine-4-acetamide (PAT) and inorganic CuII and CoII salts have been synthesized and structurally characterized by single crystal X-ray diffraction analysis. Crystal structure analysis reveals five types of architectures by variation of metal salts. In {[Cu(PAT)2Cl2]} n (1) and {[Co(PAT)2Cl2]} n (3), PAT ligands bridge metal centers to form one-dimensional chains. The chains are extended to three dimensions with the aid of two types of hydrogen bonded motifs () and (12)). {[Cu(PAT)2(NO3)](NO3)(THF)} n (5) which exhibits two-dimensional coordinating layers forms open channels filled with solvent molecules. In [Cu(PAT)2Cl2] (2), [Co(PAT)2Cl2] (4) and [Co(PAT)4(H2O)2](NO3)2(THF)2 (6), PAT is observed as a monofunctional ligand. Complex 2 forms one-dimensional hydrogen bonded chains. Crystal structure of complex 4 has a two-dimensional infinite hydrogen-bonded network with and motifs formed by complementary amide–amide hydrogen bonds. [Co(PAT)4(H2O)2](NO3)2(THF)2 (6) crystallizes in centrosymmetric I41/a space group. Complex 6 forms chiral channels which are filled with twisted solvent helices and anion helices. Within each channel the solvent helix and the anion helix have the same handedness; and adjacent channels have opposite handedness. Complexes 1, 2 and complexes 3, 4 illustrate examples of conformational supramolecular isomerism in {[Cu(PAT)2Cl2]} ∞ and {[Co(PAT)2Cl2]} ∞ , respectively. In these complexes, changes of PAT conformations and coordination geometry of metal center induced the structural versatility. [Copyright &y& Elsevier]

Abstract: Reaction of hexaazamacrocycle, 1,4,7,10,13,16-hexaazacyclooctadecane (L=[18]aneN6) with boron trifluoride etherate in an aqueous solution of hydrofluoric acid yields the proton-transfer complex of the composition [H6L(F) (BF4)5]·3H2O (1). X-ray crystallographic analysis shows that the macrocyclic cation adopts an unusual conformation to accommodate the fluoride anion and to keep the tetrafluoroborate anions in a close proximity. The tetrafluoroborate anions and water molecules participate in NH⋯F, NH⋯O and OH⋯F hydrogen bonding responsible for the 3D supramolecular architecture. [Copyright &y& Elsevier]