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(.+-.)-Tubastrindole B (Ia) and a precursor of (.+-.)-tubastrindole E (Ib) are prepared by a ring-expansion cascade of a dictazole-type precursor.

(H2DABCO) [FeIII2F8(H2O)2] (I), (H2DABCO)2 [FeIII2F10]·2H2O (II), (HDABCO)4 [FeIII2F10]·10H2O (III), and (HFDABCO)[(FeII(H2O)6) (FeIIIF6)] (IV) are prepared by conventional solvothermal synthesis using a EtOH or DMF solution of FeF2, FeF3, and HF (4%) with DABCO (autoclave, 120 °C, 72 h) to explore the composition space diagram of the (Fe2+,Fe3+)-DABCO-HFaq chemical system.

Mechanistic experiments suggest that the sequestration of free tris(pentafluorophenyl)borane by the hemilabile carboxylate contributes to the selectivity observed and prevents over reduction to methane.

(H3O)2NaAl3F12 is obtained as minor phase from the solvothermal reaction of Al(OH)3, NaOH, 1,2,4-triazole, and 40% aq.

Next to the formation of compound (IV) and several byproducts, traces of Nitrarine could be detected after very long reaction times.

The new compounds [Ni(en)3]·(TiF6) (I), [PyH]2[Cu(Py)4(TiF6)2] (II), [PyH]2[Cu(Py)4(MoF6)2] (III), [H3O]2 [SiF6(CuF(Py)4)2]·(F)2 (IV), Cu(en)2TiF6 (V), and Cu(en)2SiF6 (VI) are solvothermally synthesized from mixtures of TiO2, MoO2, SiO2, CuO or NiO, HF solution, Py, en, and EtOH (microwave heating, 160 °C, autoclave, 1 h).

Six new compounds, [H4tren][Zr2F12]·H2O (I) (tren: tris-(2-aminoethyl)amine), α-[H4tren][Zr2F12] (II), β-[H4tren][Zr2F12] (III), [H3tren]4 [ZrF8]3·4H2O (IV), α-[H3tren]2 [Ta3O2F16]F (V), and β-[H3tren]2 [Ta3O2F16]F (VI) are found to exist in the ZrF4 (Ta2O5)—tren—HFaq.—EtOH systems at 190 °C.

[(NH2)2C=NH2] 2Ti5O5F12 is synthesized by microwave-assisted solvothermal reaction of TiF4 and [(NH2)2C=NH]·HCl (EtOH, microwaves, autoclave, 190 °C, 1 h).

Two new zirconium (IV) fluorides, [H 2 dap ]·(Zr 2 F 10 )·H 2 O ( I ) and [H meam ] 2 ·(Zr 2 F 10 )·H 2 O ( II), are synthesized and characterized by X-ray diffraction, thermal techniques and NMR spectroscopy. I is triclinic ( P 1 ¯ ) with a = 6.805 (1) A, b = 8.361(1) A, and c = 11.853 (2) A, α = 94.54(1)°, β = 105.44(1)°, γ = 108.75(1)°. II is monoclinic ( C 2 /m ) with a = 10.340(6) A, b = 6.624(4) A, c = 8.758(6) A and β = 110.57(3)°. The structure determinations, performed from single crystal X-ray diffraction data, lead to the R/R w reliability factors 0.041/0.113 for I and 0.057/0.177 for II . The structures are built up from ZrF 7 and ZrF 8 units in I and only ZrF 8 units in II . The polyhedra share common edges in order to form two different ZrF 5 layers that are also found in [H 2 C 2 H 10 N 2 ]·(Zr 2 F 10 )·H 2 O and (H 3 O) 2 ·(Zr 2 F 10 )·H 2 O. On heating at 145 °C, [H 2 dap ]·(Zr 2 F 10 )·H 2 O decomposes to give the anhydrous form [H 2 dap ]·(Zr 2 F 10 ) that undergoes two successive phase transformations at 220 °C and 290 °C. 19 F NMR spectroscopy confirms the structural features of [H 2 dap ]·(Zr 2 F 10 )·H 2 O ( I ): two sets of three lines with a relative intensity 1:2:2 are attributed to five bridging fluorine atoms and to five nonbridging fluorine atoms. This spectroscopy demonstrates that a noticeable substitution of F − anions by hydroxyl OH − groups is excluded, together with the eventual substitution of H 2 O by HF molecules.

We present a systematic survey of the structural chemistry of crystalline hybrid fluorides. About a hundred different metal fluoride building units are represented in these systems, predominantly as anionic moieties, ranging from simple tetrahedral or octahedral dimers to larger oligomeric species, complex chains, layers and, ultimately, three-dimensional frameworks. Although a few compositional spaces have been moderately well explored and certain key features of their chemistries are understood, the underlying message is that this is an area still in its infancy, ripe for further and wider exploration, rich in new crystal-chemical characteristics and, perhaps, with great potential for the development of new physical and chemical functionalities.

The ions corresponding to metastable formyl loss from ionized ethylene glycol and 2-methoxyethanol are the conjugate acids of methanol and dimethyl ether, respectively. The structures of the fragments of deuterated analogues reveal that a hydroxylic hydrogen transfers to carbon to create the new methyl group, while a hydrogen originally attached to carbon migrates to oxygen in the course of this double hydrogen transfer. This is the only metastable decomposition of ethylene glycol radical cation, while 2-methoxyethanol radical cation also loses water to form oxetane radical cation

γ- and β- Lactams are easily prepared from the intramolecular ene reaction of azodicarboxyl species.

Electron-rich arenes react with bis(2,2,2-trichloroethyl) azodicarboxylate in 3 M lithium perchlorate-diethylether or acetone solution to produce para-substituted aryl hydrazides in high yields. The corresponding aromatic amines are readily obtained by reducing the hydrazides with zinc in acetic acid.

A variety of acyclic and cyclic aldehydes and ketones can be converted into the corresponding alkylidene, benzylidene and methoxycarbonyl alkylidene derivatives by treatment with 1,3,2-diazaphospholidine-2-alkyl-1,3-dimethyl 2-oxides (α-alkyl cyclic phosphonamides) under mild conditions. This olefination method is particularly useful in the case of enolizable carbonyl compounds

The structure of sodium europium fluorocarbonate, Na 2 Eu(CO 3 )F 3 , obtained by hydrothermal growth, has been determined by single-crystal X-ray diffraction. The orthorhombic structure comprises EuO 3 F 6 polyhedra linked by triangular faces and edges. Infinite EuO 2 F 3 sheets in the ab plane are connected by the carbonate groups and Na atoms

Single crystals of barium scandium fluorocarbonate, Ba 3 Sc(CO 3 )F 7 , were obtained by hydrothermal growth at high temperature and high pressure. The structure solved from single-crystal X-ray diffraction data, comprises Ba and Sc polyhedra which form connected layers parallel to (001)

The crystal structure of KGd(CO3)F2 is solved from single crystal X-ray diffraction, and the luminescence properties of KGd(CO3)F2 are analysed. KGd(CO)3F2:Eu3+ is orthorhombic, of space group Fddd (No. 70), with a=7.006(2) A, b=11.181(3) A and c=21.865(6) A. The three-dimensional network is built up from infinite sheets of GdO4F4 polyhedra in the (a, b) plane, which are linked by the carbonate groups and K+ ions along c. A single crystallographic site for Eu3+ with C2 symmetry, as predicted by X-ray study, is confirmed from the luminescence spectrum recorded at 77 K. Simulation of the crystal field effects is also carried out.

A series of 2,3-diarylthiophene compounds was prepared and their biological activities were evaluated against human Cox-1 and Cox-2 enzymes. It appears that the methylsulfone group is essential for both the activity and selectivity for the Cox-2 enzyme. Removal of the methylsulfone group gave relatively selective Cox-1 inhibitors.

Structure-activity studies leading to the discovery of a new series of non-quinoline cysLT 1 receptor (LTD 4 receptor) antagonists are described. These studies demonstrated that the quinoline ring system of montelukast ( 5 ) may be replaced by an appropriately substituted thienopyridine system, yielding potent compounds. Two other molecular features of montelukast, the terminal phenyl ring substitution and the vinyl link, were also reevaluated. These studies led to the identification of 1 (L-740,515) , a compound with optimized in vitro and in vivo biological profiles.

The transition state structures for the addition of maleic acid anhydride and methyl phenylpropiolate to 1-phenyl-3,4-dimethylphosphole were generated with the AM1 semiempirical method. The competitive transition state structures for 1,5-phenyl rearrangement in 1-phenyl-3,4-dimethylphosphole was also optimized with AM1. The energies were evaluated with the SVWN and Becke3LYP DFT methods using a 6-31G(d) basis set. The reaction outcome based on the evaluated energies were discussed and compared with experimental observations.

A series of 5,6-diarylthiazolo[3,2-b][1,2,4]triazoles was prepared for evaluation of potency and selectivity against human COX-1 and COX-2 enzymes. This lead to the discovery of L-768,277, a potent and selective COX-2 inhibitor that also demonstrated good in vivo activity.

A new class of potent ligand for the human peripheral cannabinoid (hCB 2 ) receptor is described. Two indole analogs 13 and 17 exhibited nanomolar potencies (K i ) with good selectivity for the hCB 2 receptor over the human central cannabinoid (hCB 1 ) receptor.