1-Methyl-2,4-bis-(2-methoxy-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one

The crystal structure of the title compound, C(23)H(27)NO(3), shows that the compound exists in a chair-chair conformation with an equatorial disposition of 2-methoxy-phenyl groups at an angle of 39.94 (3)° with respect to each other. An inter-molecular N-H⋯π inter-action is observed in the crystal packing.

Cisplatin ototoxicity and protection: clinical and experimental studies

Cisplatin is a chemotherapeutic agent that is widely used to treat a variety of malignant tumors. Serious dose-limiting side effects like ototoxicity, nephrotoxicity and neurotoxicity occur with the use of this agent. This review summarizes recent important clinical and experimental investigations of cisplatin ototoxicity. It also discusses the utility of protective agents employed in patients and in experimental animals. The future strategies for limiting cisplatin ototoxicity will need to avoid interference with the therapeutic effect of cisplatin in order to enhance the quality of life of patients receiving this important anti-tumor agent.

Role of beta-arrestin1/ERK MAP kinase pathway in regulating adenosine A1 receptor desensitization and recovery

Exposure of cells to adenosine receptor (AR) agonists leads to receptor uncoupling from G proteins and downregulation of the A(1)AR. The receptor levels on the cell surface generally recover on withdrawal of the agonist, because of either translocation of the sequestered A(1)AR back to plasma membrane or de novo synthesis of A(1)AR. To examine the mechanism(s) underlying A(1)AR downregulation and recovery, we treated ductus deferens tumor (DDT(1) MF-2) cells with the agonist R-phenylisopropyladenosine (R-PIA) and showed a decrease in membrane A(1)AR levels by 24 h, which was associated with an unexpected 11-fold increase in A(1)AR mRNA. Acute exposure of these cells to R-PIA resulted in a rapid translocation of beta-arrestin1 to the plasma membrane. Knockdown of beta-arrestin1 by short interfering RNA (siRNA) blocked R-PIA-mediated downregulation of the A(1)AR, suppressed R-PIA-dependent ERK1/2 and activator protein-1 (AP-1) activity, and reduced the induction of A(1)AR mRNA. Withdrawal of the agonist after a 24-h exposure resulted in rapid recovery of plasma membrane A(1)AR. This was dependent on the de novo protein synthesis and on the activity of ERK1/2 but independent of beta-arrestin1 and nuclear factor-kappaB. Together, these data suggest that exposure to A(1)AR agonist stimulates ERK1/2 activity via beta-arrestin1, which subserves receptor uncoupling and downregulation, in addition to the induction of A(1)AR expression. We propose that such a pathway ensures both the termination of the agonist signal and recovery by priming the cell for rapid de novo synthesis of A(1)AR once the drug is terminated.

A new synthetic route to Lindqvist type clusters [(n-Bu4N)x][M'M5O19] [when x = 2, M' = M = Mo or W; x = 3, M' = Mo, M = W] from metal carbonyl precursors [(CO)5ML] [M = Mo, W; L= CO, C(OMe)(Me)]

Two fully oxidized [(n-Bu4N)2][Mo6O19], 7 and [(n-Bu4N)2][W6O19], 8 and one mixed-metal, mixed-valence one electron reduced [(n-Bu4N)3][MoW5O19], 9 cluster have been synthesized under biphasic reaction conditions from group VI metal carbonyls or Fischer carbene complexes, [(CO)5M=C(OMe)Me] (M = Mo, W) in yields of 73, 77 and 71% respectively. All the clusters have been characterized by IR, 1H and 13C NMR spectra, and crystal structure determinations. Additionally, the composition of 9 has also been supported by mass spectrometry (MALDI-TOF), inductively coupled plasma (ICP) and energy-dispersive X-ray (EDX) analysis. This novel and mild route offers distinct improvements over earlier methods of synthesis for Lindqvist type mixed-valence mixed-metal polyoxometalate cluster.

2,4-Bis(2-fluoro-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one

The title compound, C₂₀H₁₉F₂NO, exists in a twin-chair conformation with an equatorial orientation of the two 2-fluoro­phenyl groups on both sides of the secondary amine group. The benzene rings are orientated at an angle of 25.68 (4)° with respect to one another and the F atoms point upwards (towards the carbonyl group). The crystal is stabilized by an inter­molecular N—H⋯π inter­action.

2,4-Bis(2-methoxy-phenyl)-3-aza-bicyclo-[3.3.1]nonan-9-one

In the title compound, C(22)H(25)NO(3), the mol-ecule has a pseudo-mirror plane. The structure is a positional isomer of 2,4-bis(4-methoxy-phenyl)-3-aza-bicyclo-[3.3.1]nonan-9-one [Cox, McCabe, Milne & Sim (1985 ▶). J. Chem. Soc. Chem. Commun. pp. 626-628]. The 3-aza-bicyclo-[3.3.1]nonan-9-one moiety adopts a double chair conformation with equatorial orientations of both 2-methoxy-phenyl substituents on either side of the secondary amino group. The benzene rings are oriented at an angle of 33.86 (4)° with respect to each other and the meth-oxy groups point towards the carbonyl group. The crystal structure is stabilized by intermolecular N-H⋯π inter-actions.

2,4-Bis(4-bromo-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one

The title compound, C₂₀H₁₉Br₂NO, shows a chair–chair conformation for the aza­bicycle with an equatorial disposition of the 4-bromo­phenyl groups [dihedral angle between the aromatic rings = 16.48 (3)°]. In the crystal, a short Br⋯Br contact [3.520 (4) Å] occurs and the structure is further stabilized by N—H⋯O hydrogen bonds and C—H⋯O inter­actions.

Antenatal diagnosis of achondrogenesis type II

Achondrogenesis is a lethal congenital chondrodystrophy characterized by extreme micromelia, small thorax and polyhydramnios. We describe a case of achondrogenesis type II (Langer-Saldino achondrogenesis). Prenatal ultrasonography at 22-weeks gestation revealed a fetus with large head, short neck and chest, prominent abdomen and short limbs. Pregnancy was terminated. Radiologic examination of neonate revealed features of achondrogenesis type II. Routine ultrasound screening made early detection and timely management possible.

Antenatal Diagnosis of Achondrogenesis Type II

Achondrogenesis is a lethal congenital chondrodystrophy characterized by extreme micromelia, small thorax and polyhydramnios. We describe a case of achondrogenesis type II (Langer-Saldino achondrogenesis). Prenatal ultrasonography at 22-weeks gestation revealed a fetus with large head, short neck and chest, prominent abdomen and short limbs. Pregnancy was terminated. Radiologic examination of neonate revealed features of achondrogenesis type II. Routine ultrasound screening made early detection and timely management possible.Key Words: achondrogenesis, antenatal, chondrodystroph, congenital

2,4-Bis(3-chloro-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one

In the mol-ecular structure of the title compound, C(20)H(19)Cl(2)NO, the bicyclic system adopts a twin-chair conformation with equatorial orientations of both substituents. The dihedral angle between the aromatic rings is 43.60 (2)° with respect to each other. The crystal structure is stabilized by weak N-H⋯O and strong C-H⋯O inter-actions.

2,4-Bis(4-chloro-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one

In the mol­ecular structure of the title compound, C₂₀H₁₉Cl₂NO, the mol­ecule exists in a twin-chair conformation with equatorial dispositions of the 4-chloro­phenyl groups on both sides of the secondary amino group; the dihedral angle between the aromatic ring planes is 31.33 (3)°. The crystal structure is stabilized by N—H⋯O inter­actions, leading to chains of molecules.

N-[Morpholino(phen-yl)meth-yl]benzamide

The title compound, C₁₈H₂₀N₂O₂, crystallizes with two mol­ecules in the asymmetric unit. The morpholine rings of both mol­ecules adopt chair conformations. The crystal structure is stabilized by inter­molecular N—H⋯O hydrogen bonds. One phenyl ring is disordered over two orientations in a 0.665 (5):0.335 (5) ratio.

2,4-Bis(2-bromo-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one

In the mol­ecular structure of the title compound, C₂₀H₁₉Br₂NO, the fused six-membered heterocyclic and cyclo­hexane rings adopt a twin-chair conformation with equatorial orientations of all the substituents. Both the ortho-bromo substituents of the benzene rings are oriented towards the carbonyl group; the dihedral angle between the ring planes is 29.13 (3)°. In the crystal structure, the N—H group does not participate in any hydrogen bonds.

2,4-Bis(3-bromo-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one

The complete mol­ecule of the title compound, C₂₀H₁₉Br₂NO, is generated by crystallographic mirror symmetry, with two C, one O and one N atom lying on the mirror plane. The compound exists in a twin-chair conformation with equatorial dispositions of the 3-bromo­phenyl groups [dihedral angle between rings = 27.37 (3)°]. The packing is stabilized by weak N—H⋯O and C—H⋯O inter­actions.

6-Formyl-2-methoxy-3-nitrophenyl 4-toluenesulfonate

In the title compound, C₁₅H₁₃NO₇S, the inter­planar angle between the two aromatic rings is 26.04 (3)°. The crystal structure is stabilized by C—H⋯O interactions.

3-Benzyl-idene-6-methoxy-chroman-4-one

In the title compound, C₁₇H₁₄O₃, the dihedral angle between the phenyl ring and the benzene ring of the chromanone moiety is 67.78 (3)°. The six-membered heterocyclic ring of the chromanone moiety adopts a half-chair conformation. The structure is stabilized by weak inter­molecular C—H⋯O inter­actions that link the mol­ecules into inversion dimers.

2,4-Bis(4-fluoro-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one

In the title compound, C(20)H(19)F(2)NO, a crystallographic mirror plane bis-ects the mol-ecule, passing through the N, O and two C atoms of the central ring system. The mol-ecule exists in a twin-chair conformation with equatorial dispositions of the 4-fluoro-phenyl groups on both sides of the secondary amino groups; the dihedral angle between the aromatic ring planes is 28.67 (3)°.

2,4-Bis(3-fluoro-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one

The title compound, C(20)H(19)F(2)NO, exhibits a chair-chair conformation, with the aryl groups in the heterocycle in equatorial orientations and oriented at an angle of 33.35 (3)° to one another. A crystallographic mirror plane, passing through the N atom, the C and O atoms of the carbonyl group and the C atom in the 7-position, bis-ects the mol-ecule. The mol-ecular structure is stabilized by one C-H⋯N inter-action and the crystal structure is stabilized by a weak C-H⋯π inter-action.