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1.  Deletion of TAK1 in the Myeloid Lineage Results in the Spontaneous Development of Myelomonocytic Leukemia in Mice 
PLoS ONE  2012;7(12):e51228.
Previous studies of the conditional ablation of TGF-β activated kinase 1 (TAK1) in mice indicate that TAK1 has an obligatory role in the survival and/or development of hematopoietic stem cells, B cells, T cells, hepatocytes, intestinal epithelial cells, keratinocytes, and various tissues, primarily because of these cells’ increased apoptotic sensitivity, and have implicated TAK1 as a critical regulator of the NF-κB and stress kinase pathways and thus a key intermediary in cellular survival. Contrary to this understanding of TAK1’s role, we report a mouse model in which TAK1 deletion in the myeloid compartment that evoked a clonal myelomonocytic cell expansion, splenomegaly, multi-organ infiltration, genomic instability, and aggressive, fatal myelomonocytic leukemia. Unlike in previous reports, simultaneous deletion of TNF receptor 1 (TNFR1) failed to rescue this severe phenotype. We found that the features of the disease in our mouse model resemble those of human chronic myelomonocytic leukemia (CMML) in its transformation to acute myeloid leukemia (AML). Consequently, we found TAK1 deletion in 13 of 30 AML patients (43%), thus providing direct genetic evidence of TAK1’s role in leukemogenesis.
doi:10.1371/journal.pone.0051228
PMCID: PMC3519594  PMID: 23251462
2.  Variable Lengths of Stay among Ischemic Stroke Subtypes in Chinese General Teaching Hospitals 
PLoS ONE  2012;7(9):e45101.
Background
Length of stay (LOS) is one of the most important quantitative indexes that measures health service utilization within a hospital. Many studies have examined the association of three major stroke categories with LOS. Our aim is to investigate the differences of LOS among ischemic stroke subtypes, results from which are helpful to healthcare providers and government agencies to improve health care delivery efficiency.
Methodology/Principal Findings
Using the Beijing Municipal Health Bureau’s hospitalization summary reports, we performed a retrospective study among first-ever in-hospital patients with ischemic stroke (ICD-10 I63) in three general teaching hospitals in Beijing, China, from 2006 to 2010 with generalized linear model. In our study, 5,559 patients (female, 36.0%; age, 64.4±12.9 years) were included. The estimated mean LOS of ischemic stroke was 17.4±1.8 days. After adjusting for confounders, LOS of lacunar infarction (14.7 days; p<0.001) and LOS of small cerebral infarction (17.0 days; p = 0.393) were shorter than that of single cerebral infarction (17.9 days, p<0.001). LOS of multi-infarct (19.0 days; p = 0.028), brainstem infarction (19.3 days; p = 0.045), basal ganglia infarction (18.5 days; p = 0.452) and other subtypes of ischemic stroke (18.9 days; p = 0.327) were longer than that of single cerebral infarction.
Conclusions
LOS of ischemic stroke patient differes across single cerebral infarction, lacunar infarction, multi-infarct and brainstem infarction patients. The ascending order of LOS was lacunar infarction, small cerebral infarction, single cerebral infarction, basal ganglia infarction, other subtypes of ischemic stroke, multi-infarct and brainstem infarction.
doi:10.1371/journal.pone.0045101
PMCID: PMC3461000  PMID: 23028783
3.  Inhibition of EGFR/MAPK signaling reduces microglial inflammatory response and the associated secondary damage in rats after spinal cord injury 
Background
Emerging evidence indicates that reactive microglia-initiated inflammatory responses are responsible for secondary damage after primary traumatic spinal cord injury (SCI); epidermal growth factor receptor (EGFR) signaling may be involved in cell activation. In this report, we investigate the influence of EGFR signaling inhibition on microglia activation, proinflammatory cytokine production, and the neuronal microenvironment after SCI.
Methods
Lipopolysaccharide-treated primary microglia/BV2 line cells and SCI rats were used as model systems. Both C225 and AG1478 were used to inhibit EGFR signaling activation. Cell activation and EGFR phosphorylation were observed after fluorescent staining and western blot. Production of interleukin-1beta (IL-1β) and tumor necrosis factor alpha (TNFα) was tested by reverse transcription PCR and ELISA. Western blot was performed to semi-quantify the expression of EGFR/phospho-EGFR, and phosphorylation of Erk, JNK and p38 mitogen-activated protein kinases (MAPK). Wet-dry weight was compared to show tissue edema. Finally, axonal tracing and functional scoring were performed to show recovery of rats.
Results
EGFR phosphorylation was found to parallel microglia activation, while EGFR blockade inhibited activation-associated cell morphological changes and production of IL-1β and TNFα. EGFR blockade significantly downregulated the elevated MAPK activation after cell activation; selective MAPK inhibitors depressed production of cytokines to a certain degree, suggesting that MAPK mediates the depression of microglia activation brought about by EGFR inhibitors. Subsequently, seven-day continual infusion of C225 or AG1478 in rats: reduced the expression of phospho-EGFR, phosphorylation of Erk and p38 MAPK, and production of IL-1β and TNFα; lessened neuroinflammation-associated secondary damage, like microglia/astrocyte activation, tissue edema and glial scar/cavity formation; and enhanced axonal outgrowth and functional recovery.
Conclusions
These findings indicate that inhibition of EGFR/MAPK suppresses microglia activation and associated cytokine production; reduces neuroinflammation-associated secondary damage, thus provides neuroprotection to SCI rats, suggesting that EGFR may be a therapeutic target, and C225 and AG1478 have potential for use in SCI treatment.
doi:10.1186/1742-2094-9-178
PMCID: PMC3418570  PMID: 22824323
Epidermal growth factor receptor; Microglia; Spinal cord injury; Neuroinflammation
4.  The Genomic Sequence of the Chinese Hamster Ovary (CHO) K1 cell line 
Nature biotechnology  2011;29(8):735-741.
Therapeutic proteins and antibodies represent a $125 billion annual market. Chinese Hamster Ovary (CHO) derived cell lines are the preferred host cells for the production of therapeutic proteins. Here, we present a draft genomic sequence of the CHO-K1 ancestral cell line. The assembly comprises 2.45Gb genomic sequence with 24,383 predicted genes. We associate most scaffolds to 21 microfluidically-isolated chromosomes to identify chromosomal locations of genes. Furthermore, we investigate genes involved in glycosylation, which affects therapeutic protein quality, and viral susceptibility genes, which affect cell engineering and regulatory concerns. Specifically, homologs for most human glycosylation-associated genes are identified in the CHO-K1 genome, although 141 are not expressed under exponential growth. In addition, many important viral entry genes are present in the genome but not expressed, which may explain the unusual viral resistance property of CHO cell lines. We demonstrate how the availability of this genome sequence may facilitate genome-scale science for biopharmaceutical protein production.
doi:10.1038/nbt.1932
PMCID: PMC3164356  PMID: 21804562
5.  Targeting HMGB1-mediated autophagy as a novel therapeutic strategy for osteosarcoma 
Autophagy  2012;8(2):275-277.
Autophagy is a catabolic process critical to maintaining cellular homeostasis and responding to cytotoxic insult. Autophagy is recognized as “programmed cell survival” in contrast to apoptosis or programmed cell death. Upregulation of autophagy has been observed in many types of cancers and has been demonstrated to both promote and inhibit antitumor drug resistance depending to a large extent on the nature and duration of the treatment-induced metabolic stress as well as the tumor type. Cisplatin, doxorubicin and methotrexate are commonly used anticancer drugs in osteosarcoma, the most common form of childhood and adolescent cancer. Our recent study demonstrated that high mobility group box 1 protein (HMGB1)-mediated autophagy is a significant contributor to drug resistance in osteosarcoma cells. Inhibition of both HMGB1 and autophagy increase the drug sensitivity of osteosarcoma cells in vivo and in vitro. Furthermore, we demonstrated that the ULK1-FIP200 complex is required for the interaction between HMGB1 and BECN1, which then promotes BECN1-PtdIns3KC3 complex formation during autophagy. Thus, these findings provide a novel mechanism of osteosarcoma resistance to therapy facilitated by HMGB1-mediated autophagy and provide a new target for the control of drug-resistant osteosarcoma patients.
doi:10.4161/auto.8.2.18940
PMCID: PMC3336081  PMID: 22301993
osteosarcoma; HMGB1; autophagy; apoptosis; chemotherapy
6.  HMGB1 is a therapeutic target for leukemia 
High mobility group box 1 (HMGB1) is a nuclear DNA-binding protein, which functions as Damage Associated Molecular Pattern molecule (DAMP) when released from cells under conditions of stress, such as injury and infection. Recent studies indicate that HMGB1 plays an important role in leukemia pathogenesis and chemotherapy resistance. Serum HMGB1 is increased in childhood acute lymphocytic leukemia as compared to healthy control and complete remission groups. Moreover, HMGB1 is a negative regulator of apoptosis in leukemia cells through regulation of Bcl-2 expression and caspase-3 activity. As a positive regulator of autophagy, intracellular HMGB1 interacts with Beclin 1 in leukemia cells leading to autophagosome formation. Additionally, exogenous HMGB1 directly induces autophagy and cell survival in leukemia cells. Experimental strategies that selectively target HMGB1 effectively reverse and prevent chemotherapy resistance in leukemia cells, suggesting that HMGB1 is a novel therapeutic target in leukemia.
PMCID: PMC3301433  PMID: 22432086
HMGB1; leukemia; apoptosis; autophagy; chemotherapy
7.  Modulation of immune tolerance with a Chinese traditional prescription inhibits allergic rhinitis in mice 
Background:
Allergic diseases substantially affect human health and social economy. The pathogenesis is to be further understood. The effect of current therapeutic remedies on allergic diseases is not satisfactory.
Aims:
This study aimed to inhibit allergic rhinitis in a mouse model with a Chinese traditional medical prescription, Bu-Zhong-Yi-Qi-Tang.
Material and Methods:
A mouse AR model was developed with ovalbumin (OVA) plus adjuvant alum. The AR clinical symptoms and immune pathology in the nasal mucosa were assessed with the AR mouse model. Some mice were treated with Bu-Zhong-Yi-Qi-Tang via gavage-fed. The immune tolerance status in the nasal mucosa was evaluated by counting the numbers of tolerogenic dendritic cells (DC) and regulatory T cells (Treg).
Results:
After exposure to the specific antigen, OVA, the sensitized mice had AR-like symptoms including nasal itch and sneeze. The frequency of mast cells, levels of IgE/IL-4 in nasal mucosa was markedly higher in sensitized mice than naïve controls; while the levels of integration alphavbeta6 (avb6), the number of tolerogenic DCs and Tregs in nasal mucosa were significantly lower than naïve control mice. The AR-like symptoms and immune pathology and immune tolerance status in the AR nasal mucosa were substantially improved by administration with Bu-Zhong-Yi-Qi-Tang.
Conclusions:
The immune tolerance status is impaired in the AR nasal mucosa that can be improved by administering with Bu-Zhong-Yi-Qi-Tang.
doi:10.4297/najms.2011.3503
PMCID: PMC3271406  PMID: 22361496
Airways; nose; allergic rhinitis; Chinese traditional medicine; immune tolerance
8.  Value of Radiodensity Determined by Enhanced Computed Tomography for the Differential Diagnosis of Lung Masses 
Iranian Journal of Radiology  2011;8(3):145-149.
Background
Lung masses are often difficult to differentiate when their clinical symptoms and shapes or densities on computed tomography (CT) images are similar. However, with different pathological contents, they may appear differently on plain and enhanced CT.
Objectives
To determine the value of enhanced CT for the differential diagnosis of lung masses based on the differences in radiodensity with and without enhancement.
Patients and Methods
Thirty-six patients with lung cancer, 36 with pulmonary tuberculosis (TB) and 10 with inflammatory lung pseudotumors diagnosed by CT and confirmed by pathology in our hospital were selected. The mean ± SD radiodensities of lung masses in the three groups of patients were calculated based on the results of plain and enhanced CT.
Results
There were no significant differences in the radiodensities of the masses detected by plain CT among patients with inflammatory lung pseudotumors, TB and lung cancer (P > 0.05). However, there were significant differences (P < 0.01) between all the groups in terms of radiodensities of masses detected by enhanced CT.
Conclusions
The radiodensities of lung masses detected by enhanced CT could potentially be used to differentiate between lung cancer, pulmonary TB and inflammatory lung pseudotumors.
doi:10.5812/kmp.iranjradiol.17351065.3128
PMCID: PMC3522332  PMID: 23329931
Tomography, X-Ray Computed; Lung; Tuberculosis, Pulmonary
9.  Ethyl 4-chloro-3,5-dinitro­benzoate 
In the title compound, C9H7ClN2O6, the nitro groups and the ester group make dihedral angles of 44.0 (1), 89.6 (1) and 164.1 (1)°, respectively, with the benzene ring. In the crystal, mol­ecules are linked through weak C—H⋯O hydrogen-bonding inter­actions. Mol­ecules are stacked via π–π inter­actions about inversion centers, with a centroid–centroid distance of 3.671 (2) Å.
doi:10.1107/S160053681103978X
PMCID: PMC3247331  PMID: 22219949
10.  A critical role for UVRAG in apoptosis 
Autophagy  2011;7(10):1242-1244.
Autophagy and apoptosis are tightly regulated biological processes that are crucial for cell growth, development and tissue homeostasis. UVRAG (UV radiation resistance-associated gene), a mammalian homolog of yeast Vps38, activates the Beclin 1/PtdIns3KC3 (class III phosphatidylinositol-3-kinase) complex, which promotes autophagosome formation. Moreover, UVRAG promotes autophagosome maturation by recruiting class C Vps complexes (HOPS complexes) and Rab7 of the late endosome. We found that UVRAG has anti-apoptotic activity during tumor therapy through interactions with Bax. UVRAG inhibits Bax translocation from the cytosol to mitochondria during chemotherapy- or UV irradiation-induced apoptosis of human tumor cells. Moreover, deletion of the UVRAG C2 domain abolishes Bax binding and anti-apoptotic activity. These results suggest that, in addition to its previously recognized pro-autophagy activity in response to starvation, UVRAG has cytoprotective functions in the cytosol that control the localization of Bax in tumor cells exposed to apoptotic stimuli.
doi:10.4161/auto.7.10.16507
PMCID: PMC3210309  PMID: 21606679
UVRAG; Bax; apoptosis; autophagy; mitochondria; tumor therapy
11.  Isopropyl 4-nitro­benzoate 
In the mol­ecule of the title compound, C10H11NO4, the nitro group is approximately coplanar with the benzene ring [dihedral angle = 4.57 (10)°], while the carboxyl­ate group is slightly twisted, making an angle of 12.16 (8)°. In the crystal, weak inter­molecular C—H⋯O hydrogen bonding and π–π stacking inter­actions [centroid–centroid distances = 3.670 (2) and 3.665 (2) Å] are observed.
doi:10.1107/S1600536811039407
PMCID: PMC3201251  PMID: 22058830
12.  A Novel, Broad Spectrum Anti-Cancer Compound Containing the Imidazo[4,5-e][1,3]diazepine Ring System 
Synthesis and broad-spectrum anticancer activity of a novel heterocyclic compound 1 containing the title imidazo[4,5-e][1,3]diazepine ring system have been reported. The compound shows potent in vitro antitumor activity with low micromolar IC50’s against prostate, lung, breast, and ovarian cancer cell lines tested. The long alkyl chain attached to the 6-position of the heterocyclic ring of 1 appears to be necessary for the observed biological activity.
doi:10.1016/j.bmcl.2010.06.061
PMCID: PMC2905507  PMID: 20594843
imidazo[4 5-e][1 3]diazepine analogue; synthesis; in vitro screening; broad-spectrum anticancer activity; prostate; lung; breast and ovarian cancers
13.  How does plasma membrane surface area accommodate alterations in guard cell volume during stomatal closing? 
Plant Signaling & Behavior  2010;5(11):1468-1469.
During stomatal movement, guard cells undergo considerable and repetitive variations in cell volume and consequently surface area over a period of minutes. Due to limited stretching capability of the plasma membrane, alterations in the surface area must accommodate the volume changes through membrane turnover. Using fluorescence imaging and electrophysiology techniques, extensive studies imply that endocytosis may be a critical mechanism for the plasma membrane turnover. In contrast to the conventional studies, using transmission electronic microscope in combination with laser confocal microscope so that the membrane turnover can be detected without a resolution limitation, our works, recently published in the Journal of Experimental Botany, has provided strong evidences that excretion and folding of plasma membrane are critical for the accommodation of the cell volume alterations in intact guard cells in Vicia faba L. These results have opened a new perspective on the mechanism for the membrane turnover during stomatal movement. In this addendum, we further discuss some key issues about the mechanisms for the accommodation of the cell volume alterations during stomatal movements.
doi:10.4161/psb.5.11.13470
PMCID: PMC3115257  PMID: 21051937
stomata; guard cell; plasma membrane; surface area; endocytosis; excretion; accommodation
14.  Autophagy regulates myeloid cell differentiation by p62/SQSTM1-mediated degradation of PML-RARα oncoprotein 
Autophagy  2011;7(4):401-411.
PML-RARα oncoprotein is a fusion protein of promyelocytic leukemia (PML) and the retinoic acid receptor-α (RARα) and causes acute promyelocytic leukemias (APL). A hallmark of all-trans retinoic acid (ATRA) responses in APL is PML-RARα degradation, which promotes cell differentiation. Here, we demonstrated that autophagy is a crucial regulator of PML-RARα degradation. Inhibition of autophagy by short hairpin (sh) RNA that target essential autophagy genes such as ATG1, ATG5 and PI3KC3, and by autophagy inhibitors (e.g., 3-methyladenine), blocked PML-RARα degradation and subsequently granulocytic differentiation of human myeloid leukemic cells. In contrast, rapamycin, the mTOR kinase inhibitor, enhanced autophagy and promoted ATRA-induced PML-RARα degradation and myeloid cell differentiation. Moreover, PML-RARα co-immunoprecipitated with the ubiquitin-binding adaptor protein p62/SQSTM1, which is degraded through autophagy. Furthermore, knockdown of p62/SQSTM1 inhibited ATRA-induced PML-RARα degradation and myeloid cell differentiation. The identification of PML-RARα as a target of autophagy provides new insight into the mechanism of action of ATRA and its specificity for APL.
doi:10.4161/auto.7.4.14397
PMCID: PMC3127220  PMID: 21187718
autophagy; differentiation; oncoprotein; leukemia; degradation; PML-RARa; p62/SQSTM1
15.  DAMP-mediated autophagy contributes to drug resistance 
Autophagy  2011;7(1):112-114.
Damage-associated molecular pattern molecules (DAMPs) are cellularly derived molecules that can initiate and perpetuate immune responses following trauma, ischemia and other types of tissue damage in the absence of pathogenic infection. High mobility group box 1 (HMGB1) is a prototypical DAMP and is associated with the hallmarks of cancer. Recently we found that HMGB1 release after chemotherapy treatment is a critical regulator of autophagy and a potential drug target for therapeutic interventions in leukemia. Overexpression of HMGB1 by gene transfection rendered leukemia cells resistant to cell death; whereas depletion or inhibition of HMGB1 and autophagy by RNA interference or pharmacological inhibitors increased the sensitivity of leukemia cells to chemotherapeutic drugs. HMGB1 release sustains autophagy as assessed by microtubule-associated protein 1 light chain 3 (LC3) lipidation, redistribution of LC3 into cytoplasmic puncta, degradation of p62 and accumulation of autophagosomes and autolysosomes. Moreover, these data suggest a role for HMGB1 in the regulation of autophagy through the PI3KC3-MEKERK pathway, supporting the notion that HMGB1-induced autophagy promotes tumor resistance to chemotherapy.
doi:10.4161/auto.7.1.14005
PMCID: PMC3039734  PMID: 21068541
DAMP; autophagy; HMGB1; chemotherapy resistance; leukemia; PI3KC3; ERK
16.  2-Chloro­ethyl 4-nitro­benzoate 
The title compound, C9H8ClNO4, crystallizes with two mol­ecules in the asymmetric unit. In each mol­ecule, the carboxyl­ate group is nearly coplanar with the benzene ring, forming dihedral angles of 2.4 (1) and 4.9 (1)°. In the crystal, mol­ecules are linked through weak C—H⋯O and C—H⋯Cl hydrogen bonds. A short O⋯N contact of 2.7660 (19) Å occurs between the nitro groups of adjacent mol­ecules.
doi:10.1107/S1600536810038742
PMCID: PMC3009323  PMID: 21588922
17.  Ethyl 2-(2-methyl-4-nitro-1H-imidazol-1-yl)acetate 
In the title compound, C8H11N3O4, the dihedral angle between the imidazole ring and the ethyl acetate plane is 103.1 (8)°. The crystal packing is stabilized by weak inter­molecular C—H⋯O and C—H⋯N hydrogen bonds.
doi:10.1107/S1600536810037098
PMCID: PMC2983319  PMID: 21587583
18.  Glycine ethyl ester hydro­chloride 
In the crystal structure of the title compound, C4H10NO2 +·Cl− (systematic name: 3-eth­oxy-3-oxopropan-1-aminium chlor­ide), there are strong inter­molecular N—H⋯Cl, C—H⋯Cl and C—H⋯O hydrogen-bonding inter­actions between the free chloride anion and the organic cation, resulting in a two-dimensional supra­molecular network in the ab plane.
doi:10.1107/S1600536810028849
PMCID: PMC3007393  PMID: 21588405
19.  Excretion and folding of plasmalemma function to accommodate alterations in guard cell volume during stomatal closure in Vicia faba L. 
Journal of Experimental Botany  2010;61(13):3749-3758.
Stomatal movement results in large and repetitive changes in cell volume and consequently surface area. While endocytosis has been extensively studied and is thought to be a major mechanism for accommodating the volume changes as evidenced mainly by fluorescent labelling and confocal imaging, studies at the ultrastructural level in intact guard cells of stomata regulated by natural factors have never been reported. Here, it is reported that excretion and folding of the plasmalemma are critical for accommodating the volume alterations in intact guard cells in Vicia faba L. Using transmission electron microscopy in combination with laser confocal microscopy, it was observed that in fully opened stomata the plasmalemma was smooth and tightly adhered to the cell walls while a whole large vacuole appeared in the cell. In the closed stomata, besides vacuole fragmentation, endocytosis of the tonoplast rather than the plasmalemma commonly occurred. Importantly, in stomata where pore closure was induced by circadian rhythm or CO2, numerous tiny vesicles were found outside the plasmalemma and, moreover, extensive folding of the plasmalemma could also be found in some regions of the cells. Additionally, an unknown structure was found at the interface between the plasmalemma and cell walls, especially in those areas of the cell where extensive folding occurred, suggesting that plasmalemma turnover is possibly associated with an interaction between the plasmalemma and cell walls. Collectively, the results strongly indicate that excretion and folding of the plasmalemma are critical for the accommodation of the cell volume alterations during stomatal movement.
doi:10.1093/jxb/erq197
PMCID: PMC2921211  PMID: 20603284
Excretion; folding; guard cell; plasmalemma; stomata
20.  The p38 MAPK pathway is essential for skeletogenesis and bone homeostasis in mice 
The Journal of Clinical Investigation  2010;120(7):2457-2473.
Nearly every extracellular ligand that has been found to play a role in regulating bone biology acts, at least in part, through MAPK pathways. Nevertheless, much remains to be learned about the contribution of MAPKs to osteoblast biology in vivo. Here we report that the p38 MAPK pathway is required for normal skeletogenesis in mice, as mice with deletion of any of the MAPK pathway member–encoding genes MAPK kinase 3 (Mkk3), Mkk6, p38a, or p38b displayed profoundly reduced bone mass secondary to defective osteoblast differentiation. Among the MAPK kinase kinase (MAP3K) family, we identified TGF-β–activated kinase 1 (TAK1; also known as MAP3K7) as the critical activator upstream of p38 in osteoblasts. Osteoblast-specific deletion of Tak1 resulted in clavicular hypoplasia and delayed fontanelle fusion, a phenotype similar to the cleidocranial dysplasia observed in humans haploinsufficient for the transcription factor runt-related transcription factor 2 (Runx2). Mechanistic analysis revealed that the TAK1–MKK3/6–p38 MAPK axis phosphorylated Runx2, promoting its association with the coactivator CREB-binding protein (CBP), which was required to regulate osteoblast genetic programs. These findings reveal an in vivo function for p38β and establish that MAPK signaling is essential for bone formation in vivo. These results also suggest that selective p38β agonists may represent attractive therapeutic agents to prevent bone loss associated with osteoporosis and aging.
doi:10.1172/JCI42285
PMCID: PMC2898605  PMID: 20551513
21.  Dimethyl 5-amino-2,4,6-triiodo­isophthalate 
The title compound, C10H8I3NO4, crystallizes with two mol­ecules in the asymmetric unit. The I atoms and the benzene ring plane in the two mol­ecules are approximately coplanar, the I atoms deviating by −0.1631 (1), 0.0704 (1) and −0.0507 (1) Å from the mean plane of the benzene ring in one mol­ecule and by 0.1500 (1), −0.0034 (1) and −0.1213 (1) Å in the other. The planes of the ester groups are almost orthogonal to those of the benzene rings in both mol­ecules, forming dihedral angles of 83.5 (3), 76.4 (3), 97.3 (1) and 75.7 (1)°. The mean planes of the benzene rings in two mol­ecules are inclined at 69.8 (3)° with respect to each other. In the crystal, inter­molecular I⋯O inter­actions link the mol­ecules into infinite chains. In addition, N—H⋯O and non-classical C—H⋯O hydrogen bonds are observed.
doi:10.1107/S1600536810001005
PMCID: PMC2979769  PMID: 21579785
22.  2,3,5-Trimethyl-1,4-hydro­quinone 
The mol­ecule of the title compound, C9H12O2, is approximately planar (mean atomic deviation = 0.0346 Å) and disposed about a crystallographic centre of symmetry. The H atom of the benzene ring is disordered over four orientations, with occupancies of 0.100 (3) and 0.401 (3) at the C atoms in the 2- and 3-positions and the same at their symmetric location. The H atoms of methyl group at the 2-position are disordered over two positions of equal occupancy. In the crystal structure, adjacent mol­ecules are linked through O—H⋯O hydrogen bonds, forming a two-dimensional network.
doi:10.1107/S1600536810000140
PMCID: PMC2979790  PMID: 21579736
23.  Methyl 4-chloro-3,5-dinitro­benzoate 
In the mol­ecule of the title compound, C8H5ClN2O6, the two nitro groups and the ester group make dihedral angles of 29.6 (1)°, 82.3 (1)° and 13.7 (1)°, respectively, with the benzene ring. In the crystal structure weak C—H⋯O inter­actions are present.
doi:10.1107/S1600536809051630
PMCID: PMC2980218  PMID: 21580164
24.  4,7-Diphenyl-2,9-bis­(trichloro­meth­yl)-1,10-phenanthroline 
In the title compound, C26H14Cl6N2, the phenanthroline ring system is essentially planar, with an r.m.s. deviation of 0.048 (6) Å, and makes dihedral angles of 64.8 (14) and 66.6 (6)° with the two terminal phenyl rings. One of the trichloro­methyl groups is disordered over two positions, with occupancies of 0.42 (2) and 0.58 (2).
doi:10.1107/S1600536809051071
PMCID: PMC2980224  PMID: 21580152
25.  Diethyl 5-amino-2,4,6-triiodo­isophthalate 
The title compound, C12H12I3NO4, crystallizes with two mol­ecules in an asymmetric unit. In one of the mol­ecules, the conformation of the O—C—O—C in one ester group is cis and trans in the other. The corresponding conformations for both the ester groups in the other mol­ecule are trans. The I atoms and the benzene rings in the two mol­ecules are approximately coplanar, the I atoms deviating by 0.219 (14), 0.056 (15) and −0.143 (14) Å from the mean plane of the benzene ring in one mol­ecule and 0.189 (14), −0.162 (15) and −0.068 (14) Å in the other. The planes of the ester groups are almost orthogonal to those of the benzene rings in both mol­ecules, forming dihedral angles of 88.1 (4), 72.2 (4), 73.0 (4) and 86.6 (4)°. The mean planes of the benzene rings in the two mol­ecules are inclined at 74.6 (4)° with respect to each other. In the crystal, inter­molecular I⋯O inter­actions [3.138 (7) and 3.144 (7) Å] link the mol­ecules into infinite chains along the a axis. In addition, non-classical C—H⋯O hydrogen bonds are observed.
doi:10.1107/S1600536809051149
PMCID: PMC2980246  PMID: 21579990

Results 1-25 (44)