bluuebunny/crossref_metadata_2025 huggingface dataset:
Subjektive Gesundheit und Erwerbslosigkeit in Deutschland auf Basis der EU-SILC-Daten von 2005 bis 2014
Authors: Hollederer Alfons , Wildner Manfred
Published: November 2018

Hintergrund Die Untersuchung zielt darauf, den subjektiven Gesundheitszustand und chronische Gesundheitseinschränkungen in der Erwerbsbevölkerung zu untersuchen und Disparitäten zwischen sozialen Gruppen zu explorieren.

Methodik Der EU-SILC-Survey wird als Haushaltsbefragung seit dem Jahr 2005 in Deutschland jährlich durchgeführt. Die Erhebung umfasste in Deutschland im EU-SILC 2014 eine Zufallsstichprobe von 22 695 Personen ab 16 Jahren (darunter 860 Erwerbslose und 11 390 Erwerbstätige).

Ergebnisse Nach den EU-SILC-Surveys 2005–2014 verbesserte sich die subjektive Gesundheit in der Bevölkerung in Deutschland. 65,2% der Befragten im Alter ab 16 Jahren berichteten eine sehr gute oder gute Gesundheit trotz zunehmender Alterung der Bevölkerung in 2014 (vs. 60,7% in 2005). Die gesundheitliche Ungleichheit stieg zwischen den Erwerbsstatusgruppen jedoch an. Von den Erwerbslosen bewerteten nur 37,2% ihre Gesundheit als sehr gut oder gut in 2014, während bei den Erwerbstätigen dieser Anteil mit 77,1% erheblich höher lag (53,8 vs. 73,2% in 2005). Multivariate logistische Regressionsanalysen für den EU-SILC-Survey 2014 ergeben starke Assoziationen bei selbstbewerteten Gesundheitszustand und chronische Gesundheitseinschränkungen mit Alter und sozialen Determinanten. In der Querschnittsbetrachtung haben Erwerbslose im Vergleich zu Erwerbstätigen eine wesentlich geringere Chance auf einen sehr guten oder guten Gesundheitszustand (OR=0,26) und eine höhere Auftrittswahrscheinlichkeit von chronischen Gesundheitseinschränkungen (OR=3,99) bei Adjustierung von sozio-demografischen Merkmalen. Die Zunahme des Nettoäquivalenzeinkommens und des Bildungsniveaus geht mit verbesserten Gesundheitsprognosen und reduzierten Risiken für chronische Gesundheitseinschränkungen einher. 78,8% der Befragten im höchsten Quintil beim Nettoäquivalenzeinkommens berichteten einen sehr guten oder guten Gesundheitszustand im Gegensatz zu 51,7% im niedrigsten Einkommens-Quintil (OR=2,53). Die Angehörigen von armutsgefährdeten Haushalten geben im Durchschnitt eine schlechtere Gesundheit in allen untersuchten Altersgruppen an. Hoher Bildungsabschluss ist mit besserem subjektivem Gesundheitszustand assoziiert (OR=1,78).

Diskussion Der EU-SILC Survey zeigt zum einen positive Gesundheitsentwicklungen und zum anderen gesundheitliche Ungleichheiten in Deutschland auf. Der EU-SILC-Survey eignet sich als jährliche Wiederholungsbefragung für ein Monitoring von Public Health-Zielen und der Reduktion gesundheitlicher Ungleichheit.
Synthesis of Novel Isoquinolino[5,4-ab]phenanthridine Derivatives via Pictet–Spengler Reaction
Authors: Shih Tzenge-Lien , Tsai Min-Chen , Huang Pei , Syu Liang
Published: November 2018

The reaction of 5-amino-2-[2-(dimethylamino)ethyl]-6-phenyl-1H-benzo[de]isoquinoline-1,3(2H)-dione with a series of aldehydes in acidic media (phosphoric acid, trifluoromethanesulfonic acid, and trifluoroacetic acid) is described. This key step is based on the Pictet–Spengler reaction to synthesize ten novel isoquinolino[5,4-ab]phenanthridine derivatives. The most effective acid is phosphoric acid and optimized yields were obtained. The frameworks of target compounds are unique and have never been reported.
Surgical Strategy in Large Vestibular Schwannoma
Authors: Klironomos Georgios , Dehdashti Amir Reza
Published: November 2018

Particular care to facial nerve function preservation should be the ultimate goal in surgery for large vestibular schwannomas. We present a 60-year-old patient who presented with an enlarging right vestibular schwannoma and nonserviceable hearing. The patient was operated in the semisitting position after a patent foramen ovale was ruled out. During the positioning, the feet were positioned at the level of the heart. Precordial Doppler was used to monitor for air embolism. Straight skin incision and retrosigmoid craniotomy was performed. Specific attention to venous bleeding was made during the approach. Meticulous arachnoid dissection of the capsule preserving the arachnoid plane at the surface of the brain stem and the facial nerve can be achieved more efficiently with the patient in the semisiting position and with bimanual microdissection technique. After drilling of the internal auditory canal (IAC), we were able to achieve near total removal of the tumor, leaving a tiny tumor carpet due to extreme adherence to the nerve. Water-tight dura closure and replacement of the bone flap was performed. The patient woke up with a House–Brackmann grade III facial weakness which improved to grade I at 6 weeks postoperatively. Postoperative magnetic resonance imaging (MRI) showed a tiny residual at the surface of the facial nerve at the entrance of the IAC. Near total (> 98%) resection of large vestibular schwannomas is an acceptable surgical strategy with excellent facial nerve outcome. With appropriate patient positioning in semisitting and proper anesthesiological and surgical management, the risk of air embolism is negligible.

The link to video can be found at: https://youtu.be/ErG9VexbiGw.
Functioning Pituitary Adenoma with Xanthogranulomatous Features: Review of Literature and Case Report
Authors: Vasquez Ciro A. , Downes Angela , Kleinschmidt-DeMasters Bette K. , Youssef A Samy
Published: November 2018

Objectives We present a patient with a prolactin-secreting adenoma with extensive secondary, noninfectious, xanthogranulomatous changes due to remote intratumoral bleeding and provide a literature review of xanthogranulomas (XGs) of the sellar region with emphasis on prolactinomas with xanthogranulomatous features.

Design Case report, with PubMed search of cases of sellar XG, focusing on neuroimaging and surgical approach.

Results A 35-year-old male was found to have a large sellar/suprasellar calcified/cystic mass. Endoscopic transsphenoidal approach for extradural resection was performed and diagnosis made. Review generated 31 patients with the diagnosis of sellar XG. In a minority (6 patients), the underlying lesion for the XG was a pituitary adenoma. Headache was the most common presenting symptom and panhypopituitarism the most common endocrinological abnormality. Examples of hyperprolactinemia associated with sellar XG are also uncommon and due to stalk effect. Neuroimaging of XG on T1-weighted magnetic resonance imaging (MRIs) showed 18 cases (56.3%) were hyperintense, 1 case (3.13%) was isointense, 4 (12.5%) had mixed-signal intensity, and 2 (6.25%) were hypointense. On T2-weighted MRIs, five lesions (15.6%) were hyperintense, three (9.38%) were isointense, nine (28.1%) were heterogeneous, and nine (28.1%) were hypointense. Only one case (3.1%) had calcifications on computed tomography scan similar to ours. In 14 cases (43.7%), the lesions enhanced with contrast administration on MRI.

Conclusion Prolactinomas with secondary xanthogranulomatous change represent a rare cause of XG of the sella. With no radiological or clinical signs specific for XG of the sellar region, preoperative diagnosis can be challenging, if not impossible.
Self-Care Support for Patients with Gastrointestinal Cancer: iCancerHealth
Authors: Berry Donna , Blonquist Traci , Nayak Manan , Grenon Nina , Momani Thaer , McCleary Nadine
Published: November 2018

Background Patient-centered symptom assessment and management tools allow patients to perform self-assessments and engage in self-symptom management. Efficacious tools exist for reducing symptom distress; however, little is known about feature-specific use.

Objectives This article evaluates the feasibility of the iCancerHealth app as an adjunct to usual patient education regarding cancer symptoms and medication management.

Methods We conducted a single-arm, pilot study grounded in the health outcomes model. Our evaluation included (1) enrollment rates, (2) 2-month utilization rates, (3) patient acceptability, and (4) clinician satisfaction with the provider-side application. English-speaking, adult patients receiving care in the gastrointestinal oncology service of a comprehensive cancer center were invited to participate. Research coordinators enrolled consenting participants who had a personal, Internet-connected device; participants registered and used the platform to complete the baseline symptom assessment in clinic. Participants were reminded weekly to use the app and to perform a symptom report 4 to 6 weeks later.

Results A total of 64 patients were approached, of which 57 (89%; 95% exact confidence interval [CI], 79–96%) enrolled. About half were ≥ 60 years old and 40% were women. Fifty-three patients (93%; 95% exact CI, 85–99%) accessed at least one app feature, at least once, from home. The most frequently used (86%) feature was Health Tracker in which participants monitored and reported symptoms; followed by My Inbox (63%) and My Medications features (60%). The mean acceptability score was 24.8 (standard deviation = 4.2), indicating good acceptability. Clinicians reported that the app was most acceptable with regard to facilitating in-person interactions that occurred after app use.

Conclusion In a sample of adults with various stages of gastrointestinal malignancies, the iCancerHealth app was utilized at a high rate. Features that focused on symptoms and medication side effects plus communication with clinicians were used most frequently. This extends our understanding of preferences and specific feature use with patient-centered technologies.
Key Word Use in Letters of Recommendation for Ophthalmology Residency Applicants According to Race, Gender, and Achievements
Authors: Aggarwal Sahil , Grob Seanna , Banerjee Dhruba , Putzel Preston , Tao Jeremiah
Published: November 2018

Objectives To identify differences in letters of recommendation (LORs) of applicants to a single ophthalmology residency program by gender, race, academic performance, and match outcome.

Design This was a retrospective analysis of LORS for 2,523 applicants (7,569 letters) to the University of California, Irvine ophthalmology residency program from 2011 to 2018.

Methods Programming scripts were employed to determine the number of times 22 key words from four thematic categories (standout words, ability, grindstone, and compassion) appeared in LORs for each applicant. A chi-square test was performed to assess for possible differences in the presence of each key word by the following characteristics: gender, underrepresented minority (URM) status, Alpha Omega Alpha (AOA) membership, the United States Medical Licensing Exam (USMLE) Step 1 score, and match outcome. Linear regressions were created to determine the frequency at which words in each thematic category appeared according to the same baseline characteristics.

Results In the LORs, females were more likely to be described as “empathetic” (p = 0.002), URMs were more likely to be described as “caring” (p = 0.002), high Step 1 scorers (≥240) were more likely to be described as “outstanding” (p = 0.002), and matched students were more likely to be described as “exceptional” (p = 0.001), “outstanding” (p < 0.001), and “superb” (p = 0.001). Standout words appeared more often in the LORs of AOA members, matched candidates, and high Step 1 scorers (p < 0.001 for all comparisons). “Competent” appeared more commonly in LORs for low Step 1 scorers (p < 0.001) and unmatched applicants (p = 0.001).

Conclusion This study identifies differences in LORs by gender, URM status, and achievement including successful ophthalmology residency match. Females and URMs were more likely to be described as “empathetic” and “caring,” respectively; otherwise, we detected no gender or racial disparities in key word use in LORs. Candidates with high USMLE Step 1 scores or AOA membership had a higher frequency of standout words in their LORs. Whether they were truly more qualified in various dimensions or if they benefited from a halo effect bias warrants further investigation. There was a significant difference in the number of standout words in LORs between matched and unmatched applicants, suggesting that key word frequency may be a relevant metric for LOR appraisal.
Note: Rotor design optimization for vacuum chamber-free ultracentrifuge
Authors: Lee Mingu , Kim Chan Seok , Kim Soohyun
Published: November 2018

This paper proposes a fixed-angle rotor design for a vacuum chamber-free ultracentrifuge using a rigid shaft and magnetic bearings. The rotor is designed for a stable operation in the ultracentrifugation region with air friction. And the optimal design parameters and optimized connection method of the rotor and rigid shaft are proposed. The proposed rotor structure can withstand a maximum rotation speed of 100 000 rpm and achieves a maximum relative centrifugal force of 600 000 g. To verify the performance of the proposed rotor design with a rigid shaft, finite-element analysis, an impact test, and a drive operating experiment were conducted.
An extended grain boundary barrier height model including the impact of internal electric field
Authors: Xu Bai-Xiang , Zhou Zi-Qi , Keil Peter , Frömling Till
Published: November 2018

An extended phenomenological model is proposed to rationalize the potential barriers of the varistor like boundaries of piezoelectric semiconductors. This model takes self-consistently into account the inverse piezoelectric effect of the internal electric field associated with the barrier height at grain boundaries. A double Schottky barrier at a grain boundary gives rise to a strong internal electric field in the depletion layer. Due to the inverse piezoelectric effect, this internal electric field leads to mechanical strain and consequently piezoelectric charge at a grain boundary and also an additional space charge associated with the polarization inhomogeneity. The piezoelectric charges in return impacts the barrier height. Results show that the piezoelectric charge induced by the internal field tends to adjust the grain boundary charge and lowers the barrier height. Furthermore, the barrier height becomes less sensitive to mechanical stress and applied voltage if the influence of the internal field is taken into account. The extended model with the inverse piezoelectric effect of the internal field allows to further elucidate their piezotronic response. The work improves the grain boundary barrier height theory of piezoelectric ceramics and is expected to have general impact on piezotronics and other junction devices.
The effect of dietary docosahexaenoic acid on the expression of lipogenic genes in broilers
Authors: Chin H. J. , Ko Y. H. , Shen T. F. , Ding S. T.
Published: November 2018

The objectives of this work were to determine the effects of dietary fungal docosahexaenoic acid (DHA) on tissue DHA concentration and lipogenic gene expression in broilers. A fungal (SR-21) meal product containing 31.5% total fat and 32.7% DHA (% of total fatty acids) was fed to chicken broilers at 0, 1, or 3% for 3 weeks. A diet with 1% DHA oil (containing 40% DHA) was also fed to chicken broilers as a positive control. Dietary fungal meal supplementation (3%) improved daily weight gain, food intake, and feed conversion ratio. The fungal meal supplementation increased dietary DHA content and consequently increased the DHA content in plasma, breast muscle (Pectoralis major), and livers in the broilers. The plasma triacylglycerol concentration was decreased by the supplementation of dietary DHA. The data indicate that the dietary DHA treatment modified certain aspects of the lipid metabolism, especially pathways related to triacylglycerol synthesis. Indeed, both the 1% DHA oil and 3% fungal meal treatments decreased the hepatic lipogenic transcription factor sterol regulatory element binding protein 1 (SREBP1) mRNA relative abundance, suggesting that dietary DHA supplementation decreases SREBP1 gene functions. The relative mRNA abundance of the de novo fatty acid synthesis genes, fatty acid synthase and acetyl coenzyme A carboxylase, was reduced by 1% DHA oil and 3% fungal meal treatments, suggesting that dietary DHA supplementation decreases lipogenesis in the livers of the broilers. Taken together, the fungal meal is a suitable dietary supplement to increase tissue DHA content and reduce the expression of hepatic lipogenic genes in broilers.
A preliminary genetic analysis of breech and tail traits with the aim of improving the welfare of sheep
Authors: Scobie D. R. , O'Connell D. , Morris C. A. , Hickey S. M.
Published: November 2018

The area of naturally bare skin around the perineum was scored at weaning in lambs (n = 2152) from a composite flock of New Zealand crossbred sheep. Breech bareness was scored on a range from 1, where wool was growing right to the edges of the anus, to 5, where a large bare area surrounded the perineum. Bareness on the under surface of the tail was measured on a linear scale at tail docking. Dag score (degree of breech soiling) was recorded at weaning, on a scale of 0–5, where an increasing score indicated more dags. Dag score was taken as a measure of the risk of flystrike in the breech. Female lambs tended to have slightly greater (P < 0.001) breech bareness score (mean score 2.7) than males (mean score 2.6), whereas mean dag score of females was lower than that of males (0.45 v. 0.53; P < 0.05). Breech bareness score had a heritability of 0.33 ± 0.06, and the length of bare skin under the tail had a heritability of 0.59 ± 0.06. The genetic correlation between breech bareness score at weaning and length of bare skin under the tail at docking was positive (0.35 ± 0.10). These 2 traits had phenotypic correlations with dag score of –0.17 ± 0.02 and –0.03 ± 0.03, respectively, and genetic correlations with dag score of –0.30 ± 0.13 and 0.03 ± 0.12, respectively; negative values indicated a favourable relationship. Tails were removed at docking, so the phenotypic correlation of about zero between tail data and dag score at weaning was of little utility. Our results suggest that selecting for these 2 bareness traits could reduce dag formation and the associated risk of breech strike.
Controlled Synthesis, Dye-fixing Performance and Dye-fixing Mechanisms on Cotton Fabric of Novel Reactive Cationic Copolymers of N,N-Diallyl-3-hydroxy-azetidinium Chloride and Dimethyldiallylammonium Chloride (P(DHAC-DMDAAC)s)
Authors: Yu Yikai , Zhang Yuejun
Published: November 2018

First, a series of novel reactive cationic copolymers (P(DHAC-DMDAAC)s) of N,N-diallyl-3-hydroxy-azetidinium chloride (DHAC) and dimethyldiallylammonium chloride (DMDAAC) with controlled structures and controlled molecular weights characterized by intrinsic viscosities of 0.11–0.89 dL g–1 were successfully synthesized by varying the molar ratios of raw materials DHAC to DMDAAC from 1 : 99 to 20 : 80 and increasing initial monomer concentrations from 35 to 55 % with a decrease of initiator amount from 7 to 3 % during polymerization. Second, it was found that the dye-fixing performance of P(DHAC-DMDAAC)s could be further increased by incorporation of 7 % molar content of DHAC units into the main chains of controlled-molecular-weight poly(dimethyldiallylammonium chloride) (PDMDAAC) dye fixatives, and their best dye-fixing performance was better than all the widely used commercial polycationic dye fixatives, indicating that the obtained P(DHAC-DMDAAC)s could be novel useful reactive polycationic dye fixatives for cotton fabric. Last, it was found from studies on dye-fixing mechanisms on cotton fabric by modern analysis techniques that the reactive units (DHAC) of the obtained P(DHAC-DMDAAC)s could form covalent bonds with the hydroxyl groups of cotton (cellulose) to give an ether linkage, resulting in strong interactions of P(DHAC-DMDAAC)s with the cotton fabric as well as the electrostatic forces between the anionic dyes and the basic cationic groups in the polymers to produce water-insoluble colour lakes, for the development of the dye fastness on cotton fabric.
Hydrogel-Derived Soft Materials for Biomimetic and Energy-Related Functions
Authors: Goudappagouda  , Wakchaure Vivek Chandrakant , Ranjeesh Kayaramkodath Chandran , Babu Sukumaran Santhosh
Published: November 2018

Supramolecular assembly of molecules leading to gelation of large amount of solvents is always a fascinating topic of research. In the very recent past, the exciting developments have marked hydrogels as intriguing materials with excellent features. Hydrogel scaffolds enable the accommodation of organic and/or inorganic guest materials to deliver diverse applications. Hydrogels have been exploited to generate soft materials with mechanical anisotropy, tunable rigidity, self-healing properties, as well as photocatalytic capabilities towards H2 production. Remarkably, the combination of a photocatalyst and a light-harvesting system in the gel matrix provides a unique means to photocatalytic H2 production. The biomimetic applications of hydrogels have also generated much attraction due to their potential demonstrations. The diverse applications underline the significance of such a soft gel medium to reach the final goal. Herein, important reports pertaining to the use of hydrogels as an effective way to generate advanced materials for biomimetic and energy-related issues are discussed.
A thermodynamic study of the dimerization of cyclopentadiene
Authors: Turnbull AG , Hull HS
Published: November 2018

The heat of dimerization of
cyclopentadiene to endo-dicyciopentadiene in the liquid phase at 25� was measured
in an adiabatic calorimeter to be -9.22 � 0.3 kcal/mole monomer. The rate of
dimerization in the liquid phase at 25� was followed with a dilatometer and the
initial second-order rate constant found to be 4.99 x 10-5. mole-l
min-l. The vapour pressure of
endo-dicyclopentadiene, measured by a boiling point method in the range
77.5-149.6�, gave the relation (p in torr):

RInp ? 11342/T -2.6505In T + 54.7855

The standard heats of
formation of solid, 31.1 � 0.5 kcal/mole, and gaseous, 42.2 � 0. 6 kcal/mole,
endo-dicyclopentadiene were derived, and the strain
energy and dimerization equilibria discussed.
Radiation-induced reactions with cellulose. VI. Copolymerization studies with monomers in wetting solvents
Authors: Dilli S , Garnett JL
Published: November 2018

Radiation-induced grafting
of three commonly used monomers to cellulose in a variety of wetting solvents
has been examined. Styrene and methyl methacrylate in both air and vacuum readily graft to cellulose in acetone, dioxan,
and dimethylformamide solvents whereas vinyl acetate under similar conditions
exhibits poor copolymerization behaviour. All three monomers do not readily
graft in n-butylamine. The grafting properties of
styrene in ethanol and propan-1-ol are similar to
those observed in methanol, whereas poor copolymerization is obtained in butan-1-ol. A
mechanistic interpretation of the observed data is discussed in terms of
current theories of radiation polymerization.
Baeyer-Villiger oxidation of Δ4-3-Oxo-steroids and 4,5-Epoxy-3-oxo-steroids. A route to some novel A-nor-steroids
Authors: Pinhey JT , Schaffner K
Published: November 2018

Evidence is presented that
the Baeyer-Villiger oxidation of Δ4-3-oxo-steroids
yields enol-e-lactones which are further oxidized to β-epoxy-e-lactones.
The latter are acid labile and rearrange to 5α-acyl-∂-lactones. The
sequence appears to be stereospecific, and no 5β-acyl-∂-lactones
could be isolated.

Baeyer-Villiger oxidation of 4,5-epoxyoholestan-3-ones
results in oxygen insertion between C3 and C4. The epoxy-e-lactones were not
isolated, since they rearranged under the acidic conditions to give 5-acyl-4-oxacholestan-3-ones. The 5α-acyl epimers
differ from the 5β-compounds, by undergoing an internal Claisen-type
condensation to give A-norcholestans with a 2,5-lactone
bridge. The photochemical, thermal,
and boron trifluoride-catalysed conversion of the enol
lactone (IIIa) into a-nor-5β-cholestan-3-one
is reported.
2-Oxothiazolidine-4-carboxylic acid and related substances
Authors: Maclaren JA
Published: November 2018

Two techniques proposed for
specific cleavage of the N-acyl cysteinyl bond in
peptides involve the formation of 2-oxothiazolidine-4-carboxyl
residues (I; Z = 0) and 2-iminothiazolidine-4-carboxyl
residues (I; Z = NH), as the new N-terminal groups. The corresponding acids
((11) and (IV) respectively) have been synthesized and their behaviour to
hydrolysis and to oxidation has been studied. Whereas (11) was decomposed by
vigorous acid hydrolysis, (IV) was stable. Oxidation of (11) gave cysteic acid, whilst (IV) gave N-carbamidocysteic
acid, and both of these oxidation products offer potential methods for
estimating the extent of the specific cleavage. The S-phenylthiocarbonyl
and S-4-nitrophenyloxycarbonyl derivatives of N-acetylcysteine (111; R = PhS or
p-NO2C6H4O) form (11) under mild alkaline conditions,
and hence the proposed cleavage mechanism is supported.
The significance of hydrogen bonding in electron solvation processes in ethanol-n-hexane liquid mixtures
Authors: Brown BJ , Barker NT , Sangster DF
Published: November 2018

Infrared spectrometry has
been used to identify the quasi-stable associated alcohol complexes significant
to electron solvation processes when ethanol-n-hexane liquid mixtures are
subjected to high energy ionizing radiation. The solvated free electron yield
is directly related to the square of the concentration of alcohol unimer
species. This result has been interpreted in terms of the electron being
solvated primarily by alcohol dimer.
An electron spin resonance study of certain vanadyl polyaminocarboxylate chelates formed in aqueous and frozen aqueous solutions
Authors: Smith TD , Boas JF , Pilbrow JR
Published: November 2018

Potentiometric pH-titration
and electron spin resonance studies have shown the existence of mono-meric, dimeric and dinuclear vanadyl chelates of certain
polyaminocarboxylic acids. The ligands studied include
ethylenediaminetetraacetic (edta), ethyleneglycolbis(β- aminoethyl ether)-N,N?-tetra-acetic
(egta), diethylenetriaminepentaacetic
(dtpa) and triethylenetetraaminehexaace-
tic (ttha) acids. All the ligands form 1 : 1
chelates. The addition of ethylene glycol to the aqueous solution in each case
provides circumstances for the study of the monomeric chelates, though it is
not equally effective in all cases. The 1 : 1 vanadyl egta
chelate above pH 5.5 gave rise to ΔMS = � 2 and ΔMS
= � 1 transitions from which structural and magnetic parameters have been determined
and interpreted in terms of the formation of a dimeric form of a hydrolytic
product of the 1 : 1 chelate. Firm evidence for the formation of dinuclear
chelates occurs only in the vanadyl ttha system. Here
the room tem- perature e.s.r. spectrum shows the
presence of weak exchange coupling between the vanadyl ions in the dinuclear
chelate.
A new conversion of nitriles into acetyl compounds: Nickel-catalysed methylation by trimethylaluminium
Authors: Bagnell L , Jeffery EA , Meisters A , Mole T
Published: November 2018

Nickel acetylacetonate
catalyses the methylation of nitriles by trimethylaluminium. Methylation occurs
in hydrocarbon solvent at near ambient temperature to give, upon hydrolysis,
acetyl compounds (RCN → RCOMe). The following nitriles have been
converted into acetyl compounds in moderate to good yields: benzonitrile,
dodecyl cyanide, benzyl cyanide, diphenylacetonitrile, p-chlorobenzo-nitrile
and glutaronitrile. Side reactions of the ketenimide formation-and- condensation
type appear to occur less than with methyllithium and methyl Grignard reagents.
Aromatic amides. IX. Temperature effects on the N.M.R. spectra of substituted acetanilides
Authors: Rae ID
Published: November 2018

N.m.r. spectra have been
measured for several anilides in dimethyl sulphoxide solution for temperatures
in the range 40-140�. The change of the N-H chemical shift with temperature
depends on the nature of the ortho substituent on the benzene ring, being least
when a strong intramolecular hydrogen bond is possible between the amide N-H and
the ortho substituent. For 2?-nitroanilides, the 6?- proton becomes
increasingly deshielded as the temperature is raised.
Cyclization of a 2-Hydroxymethylchalcone to a phthalan: 1-(2-Hydroxy-4-methoxyphenacyl)-1,3-dihydroisobenzofuran
Authors: Clark-Lewis JW , Mahandru MM
Published: November 2018

Condensation of
2-acetoxymethylbenzaldehyde with 2-hydroxy-4- methoxyacetophenone
gave a low yield of the phthalan named in the title
instead of the desired 2-hydroxymethylchalcone. The 1,3- dihydroisobenzofuran,
presumably formed by cyclization of the chalcone, showed long-range coupling between
the 1- and 3-protons as part of an ABM2X system.
Chiral Heterocyclic Ligands. II. Synthesis and Palladium(II) Complexes of Chiral Pyrazolylmethyl-Pyridines and Pyrazolylmethyl-Pyrazoles
Authors: House DA , Steel PJ , Watson AA
Published: November 2018

The syntheses of the pyrazolylmethylpyridines (5a-c), their chiral derivatives (7) and (8), and the chiral methylenebisindazoles (9)-(11) are reported. These bidentate ligands form stable 1 : 1 complexes with PdCl2. A single-crystal X-ray structure determination of dichloro [(4S,7R)-7,8,8-trimethyl-2-(pyridin-2-ylmethyl)-4,5,6,7-tetrahydro-4,7-methano-2H-indazole]palladium(II),(16), is also reported.
Structure and Conformations of Gaba-Transaminase Inhibitors. II. Transition-State Analogs
Authors: Andrews PR , Cody V , Gulbis JM , Iskander MN , Jeffrey AI , Mackay MF , Dipaola C , Sadek M
Published: November 2018

Crystal structures of two benzoxazine derivatives designed as transition state analogue inhibitors of GABA-T were determined. These cyclic oxazine structures are shown to be more similar to the proposed transition state than the pyridoxal derivatives reported in the preceding article.1 Conformational analyses (non-bonded energy, MINDO/3, MNDO) show that the crystal structures are close to the calculated energy minima. The MNDO parameterization gives geometries close to the crystal structure, with the configuration at the nitrogen of the oxazine ring in particular being better reproduced than by the MINDO/3 method, which tends to prefer planar (sp2) nitrogen.
Aggregation of Saponins and Bile Acids in Aqueous Solution
Authors: Oakenfull DG
Published: November 2018

Light scattering, viscometry , fluorescence spectroscopy, electron microscopy and equilibrium dialysis have been used to study the aggregates formed by the interactions of saponins and bile acids in aqueous solution. Purified saponins from three plant sources were used: commercial 'saponin white' (from Saponaria officinalis), quillaia saponin (from Quillaia saponaria), and saponin from soya beans. Alone, the saponins formed small micelles, dimers in the case of saponin white and soya saponin , and larger aggregates of about 50 molecules for quillaia saponin . With bile acids, the saponins formed large mixed micelles. The size and structure of these depended on the chemical structure of the saponin . Saponin white and quillaia saponin gave filamentous structures with the hydrophobic triterpene groups of the saponin forming elongated stacks interleaved with bile acid anions. Soya saponin formed very different micelles with bile acids. These had a loose, open structure with considerable interpenetration of water. These results help to explain the increased faecal excretion of bile acids which has been observed in response to foods rich in saponins.
Chemistry of the Group-1B Metals. XIX. Crystal and Molecular-Structures of (2-Phenylethynyl)(Triphenylphosphine)Gold(I), Au(C=CPh)(PPh3)
Authors: Bruce MI , Duffy DN
Published: November 2018

The molecular structure of Au(C2Ph)(PPh3) consists a gold atom almost linearly coordinated by a phenylethynyl group [Au-C 1.97(2), 2.02(2)Ǻ] and a PPh3 ligand [Au-P 2.276(5), 2.282(4)Ǻ]; a weak Au…Au interaction [3.379(1)Ǻ] holds the two independent molecules in a nearly orthogonal arrangement. Crystals are monoclinic, space group P21/c, with a 12.431(4), b 21.439(4), c
16.366(5)Ǻ, β 96.36(3)°, Z 8; 1750 independent data with I ≥ 2.5σ(I) were refined to R 0.033, Rw 0.035.
Studies of Australian Soft Corals. XXXIX. New Sesquiterpene Metabolites From Several Xenia Species (Xeniidae, Octocorallia, Anthozoa)
Authors: Bowden BF , Coll JC , Willis RH
Published: November 2018

The structures and absolute stereochemistry of three new metabolites isolated from Xenia species of soft corals have been determined by spectroscopic study and chemical correlation with known natural products. The new metabolites are: (1S,2R,4R,4aS,5Z,8aR)-1,2-epoxy-4-isopropyl-1,6-dimethyl-1,2,3,4,4a,7,8,8a-octahydronaphthalene (4), (1E,4R,4aR,5S,6R,8aR)-5,6-epoxy-4-isopropyl-6-methyl- 3,4,4a,5,6,7,8,8a-octahydronaphthalene-1-methanol acetate (5) and (1E,5Z,4R,4aR,8aR)-4-isopropyl-6-methyl-3,4,4a,7,8,8a- hexahydronaphthalene-1-methanol (6).
Potential GABAB Receptor Antagonists. VI. The Synthesis of Saclofen and Other Sulfonic Acid Derivatives
Authors: Abbenante G , Prager RH
Published: November 2018

Saclofen, 3-amino-2-(4chlorophenyl) propanesulfonic acid (3), has been synthesized by two routes. Attempts to hydrogenolyse or dehydrate the 2-hydroxy derivative were unsuccessful, however. Radical sulfonation of 3-amino-1-bromo-2-(4-chlorophenyl) propene gave 3-amino-2- (4-chlorophenyl)propene-1-sulfonic acid (6) which was readily reduced to (3). Alternatively, 2-(4-chlorophenyl)-3-phthalimidopropene underwent radical addition of thioacetic acid, and oxidation of the product to the sulfonyl chloride and hydrolysis gave (3). The corresponding sulfonamide (4) was also prepared. The acid (3) is a powerful specific antagonist of GABA at the GABAB receptor, while (4) and (6) are only weak antagonists.
Potential Antimalarials. XVI. 4'-Chloro-3-[7″-chloro(and trifluoromethyl)quinolin-4″-yl]amino-5-(substituted amino)methylbiphenyl-4-ols and 4'-Bromo(and 3'-trifluoromethyl)-3-(substituted amino)methyl-5-(7″-trifluoromethylquinolin-4″-yl)aminobiphenyl-2-ols
Authors: Barlin GB , Tian FL , Kotecka B , Rieckmann KH
Published: November 2018

Twenty-four mono-Mannich bases of the general formulae 4'-chloro-3-[7″-chloro(and trifluoro-methyl)quinolin-4'-yl]amino-5-(substituted amino)methylbiphenyl-4-ols and 4'-bromo(and 3'- trifluoromethyl-3(substituted amino)methyl-5(7″-trifluoromethylquinolin-4″-yl) aminobiphenyl-2-ols have been prepared by condensation of the 4-chloro heterocycle with 5-amino-3-(N-substituted amino)methyl-4'-chlorobiphenyl-4-ols or 5-amino-3-(N-substituted amino)methyl- 4'-bromo(or 3'-trifluoromethyl)biphenyl-2-ols. The antimalarial activity of these products in in vitro tests against Plasmodium falciparum reveals many with IC50 values of 50-100 nM ( chloroquine 20-40 nM ). The biphenyl-2-ols were more active than comparable biphenyl-4-ols.
Single-Crystal Magnetic Properties of [Co(NH3)5(OH2)] [Cr(CN)6] Between 2 and 300 K
Authors: Reynolds PA , Delfs CD , Figgis BN , Moubaraki B , Murray KS
Published: November 2018

The magnetic susceptibilities along and perpendicular to the c axis (hexagonal setting) between 2.0 and 300 K at a magnetic field of 1.00 T, and the magnetizations at field strengths up to 5.00 T, are presented for single crystals of [Co(NH3)5(OH2)] [Cr(CN)6]. The results are interpreted in terms of zero-field splitting (2D) of the ground 4A2g term by spin-orbit coupling and of magnetic exchange interaction between the chromium atoms. The magnetic exchange is modelled as one of Ising or mean-field in type. The exchange is found to be quite small: J = -0.18(6) cm-1 if the Ising model is employed, and -0.03(1) cm-1 for the mean-field model. The model adopted for the exchange has a strong influence on the value of the parameter D obtained. When the Ising model is used D is deduced to be -0.28(9) cm-l; when the mean-field model is used D is -0.14(4) cm-l. The g-values deduced are in agreement with those from e.s.r. measurements at higher temperatures and do not depend on the exchange model. In any case, D is found to be sufficiently large that it must be considered in a polarized neutron diffraction experiment on the compound.
Synthesis and Structure of cis-Dioxobis(pyrimidine-2-thiolato-N,S)molybdenum(VI)
Authors: Traill PR , Wedd AG , Tiekink ERT
Published: November 2018

The characterization of two MoVI complexes, cis -[MoO2(2-pymS)2] and cis -[MoO2(2-pyS)2] (where 2-pymSH is pyrimidine-2-thiol and 2-pySH is pyridine-2-thiol), and their reaction with Ph3P are reported. The X-ray structure of cis -[MoO2(2-pymS)2] shows the molybdenum atom to exist in a distorted octahedral geometry defined by two mutually cis oxygen atoms and two chelating 2-pymS ligands so that the two sulfur atoms occupy approximate trans positions. Crystals of cis -[MoO2(2-pymS)2] are monoclinic, space group P 21/n, with unit cell dimensions: a 9.301(3), b 12.121(2), c 11.303(3) �, β 112.62(3)�, V 1176.3 �3, Z 4. The structure was refined by a full-matrix least-squares procedure to R 0.067 for 1858 reflections with I ≥ 2.5 (I).
A Potential Surface Map of the H-/N2O System. The Gas Phase Ion Chemistry of HN2O-
Authors: Sheldon JC , Ohair RAJ , Downard KM , Gronert S , Krempp M , Depuy CH , Bowie JH
Published: November 2018

Dunkin, Fehsenfeld and Ferguson have reported that the gas phase reaction between H- and N2O in a flowing afterglow instrument forms HO- and N2 with medium efficiency. The potential surface (UMP2-FC/6-311++G**//RHF/6-311++G**) for the H-/N2O system confirms this to be the predominant reaction following initial approach of H- towards the central nitrogen of N2O to form unstable intermediate [H-(N2O)]. The intermediate then decomposes to HO- and N2 via a deep channel. The potential surface also shows the direct formation of adducts -O-+N(H)=N- and cis HN=NO-. However, these are formed with excess energy: the former converts principally into reactants, while the latter decomposes to HO- and N2. Ions having the formula 'HN2O-' may be formed in the gas phase by the reactions ( i ) HNO-+N2O → HN2O-+NO, and (ii) NH2-+Me3CCH2ONO → HN2O-+Me3CCH2OH. The product anion is stabilized by removal of some of its excess energy by the eliminated neutral. Evidence is presented which indicates that the product is either cis or trans HN=NO-, or a mixture of both. The characteristic ion molecule reaction of HN=NO- involves oxidative oxygen transfer to suitable neutral substrates. For example: HN2O-+CS2 → HS-+N2+COS.
Styrylpyrone Derivatives From Goniothalamus dolichocarpus
Authors: Goh SH , Ee GCL , Chuah CH , Wei C
Published: November 2018

Styrylpyrone derivatives (+)-goniothalamin (1), (+)-goniothalamin epoxide (2) and (–)-iso-5-deoxygoniopypyrone (4b), and the acetogenin (+)-annonacin (7) were bioactive compounds isolated from the stem bark of Goniothalamus dolichocarpus. The stereochemical relationships for (+)-goniothalamin epoxide (2), (+)-isogoniothalamin epoxide (3) and (+)-goniodiol diacetate (6) were established by chemical transformations and single-crystal X-ray crystallography.
The Chemistry of 5-Oxodihydroisoxazoles. XI. The Photolysis of 3-Hydroxy-4-phenylisoxazol-5(2H)-ones (Phenyldisic Acids)
Authors: Prager RH , Smith JA
Published: November 2018

3-Hydroxy-2-methyl-4-phenylisoxazol-5(2H)-one, 3-hydroxy-2,4-diphenylisoxazol-5(2H)-one and phenyldisic acid have been photolysed at 254 nm in hydroxylic solvents. By comparison of the respective products with those obtained from 3-methoxy-4-phenylisoxazol- 5(2H)-one, 5-methoxy-4-phenylisoxazol-3(2H)-one and 5(3)-hydroxy-2,2-dimethyl-3(5)-oxo-4-phenyldihydroisoxazolium hydroxide, it is apparent that the disic acids photolyse independently from the 3-hydroxy 5-one, the 5-hydroxy 3-one and the zwitterion tautomers. Novel photochemical pathways for these processes are suggested.
Amino Substituents as a Probe of Reactions of Phenyl Acetates With Cyclodextrins
Authors: Easton CJ , Kassara S , Lincoln SF , May BL
Published: November 2018

The effects of α- and β- cyclodextrin and 6A-amino-6A-deoxy-α- and -β- cyclodextrin on the rates of reactions of m- and p-nitrophenyl acetate, in borate buffer at pH 10.0 and 298.2 K, show that the amino substituents of the modified cyclodextrins have only a modest influence on the dissociation constants of the complexes formed with each ester and the first-order rate constants for the reactions of complexed m-nitrophenyl acetate. By contrast, the amino substituents significantly increase the rate constants for the reactions of complexes of p- nitrophenyl acetate. These results indicate that one mode of inclusion of p-nitrophenyl acetate in α- and β- cyclodextrin has the ester oxycarbonyl group in the vicinity of the cyclodextrin primary hydroxy groups. While this mode of inclusion in the unmodified cyclodextrins does not lead to reaction and has not been detected previously for that reason, in analogous complexes of the amino-substituted cyclodextrins, the nucleophilic amino group is proximate to the carboxy group of the ester and reaction proceeds. There is no kinetic evidence for this mode of inclusion of m-nitrophenyl acetate. This interpretation of the kinetic effects is consistent with the extent of acetamide formation in reactions of the esters with the amino-substituted cyclodextrins.
Free-Radical Chemistry of Imines
Authors: Tomaszewski MJ , Warkentin J , Werstiuk NH
Published: November 2018

Aryl radicals bearing an aldimino functional group as part of an ortho substituent cyclized by addition to C and/or N of the imino group. When the choice was between 5-exo closure to C and 6-endo closure to N, the former predominated. However, 6-endo closure to C predominated over 5-exo cyclization to N in isomeric imines. Absolute values of cyclization rate constants were determined and an explanation for the unusual 6-endo preference is offered. Chiral induction in 6-endo cyclization to C of an aldimine from D-glyceraldehyde acetonide was observed, and its sense was determined.
The Chemistry of Novolac Resins. I. A Review on the Use of Models
Authors: Looney MG , Solomon DH
Published: November 2018

The model systems ranging from the simple phenolic derivatives xylenol and cresol to higher oligomers such as (13), (15) and (17) are being used to study the chemistry of the curing of phenol-formaldehyde resins with hexamethylenetetramine. The key intermediates in these systems have been identified and this knowledge is being used to develop an understanding of the curing of the complex commercial resins.
Chiral 2 α,4-Dihydroxy-1,8-cineole as a Possum Urinary Metabolite
Authors: Carman RM , Rayner AC
Published: November 2018

Both enantiomers of 2α,4-dihydroxy-1,8-cineole (2) have been synthesized. The enantiomer present in possum urine is the (―)-(1R,2R,4R)-isomer (2'). This diol is biosynthesized in the possum from (1R,2R,4S)-2α-hydroxy-1,8-cineole (18).
Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. IV. Some Complexes of Group 2 Halides With Ethane-1,2-diamine
Authors: Waters AF , White AH
Published: November 2018

Syntheses and room-temperature single-crystal X-ray structure determinations are recorded for a number of adducts of ethane-1,2-diamine (en) with Group 2 metal salts, MX2.n(en). [Mg(en)3] Br2.MeOH (1) is monoclinic, P 21/c, a 9.067(5), b 15.161(4), c 14.839(8) Ǻ, β 121.86(5)°, Z = 4 f.u .; R was 0.070 for No 1226 independent 'observed' (I > 3σ(I)) diffractometer reflections; [Mg(en)3] I2.MeOH (2) is triclinic, Pī , a 11.500(2), b 9.527(6), c 8.825(4) Ǻ, α 106.30(4), β 100.57(3), γ 90.28(4)°, Z = 2 f.u .; R 0.045 for No 3562. In (1) and (2), (Mg-N) are 2.20 and 2.19 Ǻ. [Ca(en)4]Br2 (3) is orthorhombic, Fddd , a 28.54(1), b 15.863(7), c 8.927(9) Ǻ, Z = 8 f.u .; Ca-N are 2.608(7) and 2.556(8) Ǻ. [ Sr (en)4] Cl2.2MeOH (4) is also orthorhombic, Fddd , a 26.627(8), b 15.388(4), c 11.313(4) Ǻ, Z = 8 f.u .; R 0.059 for No 535. [ Sr (en)4] Br2.2en (5) is tetragonal, I 41/a, a 9.215(7), c 27.678(3) Ǻ, Z = 4 f.u ., R 0.044 for No 657. [ Sr (en)4]I2.MeOH (6) is tetragonal, I41/amd, a 9.389(1), c 28.78(1) Ǻ, Z = 4. f.u ., R 0.040 for No 10. In (4), (5) and (6), Sr -N are 2.728(7), 2.718(7); 2.720(7), 2.703(7) and 2.75(2), 2.72(7) Ǻ. [ ClBa (en)3(en)(2/2)](∞ ׀ ∞) Cl (≡ BaCl2.4en) (7) is monoclinic, P 21, a 8.666(3), b 9.063(10), c 12.655(5) Ǻ, β 108.13(3)°, Z = 2 f.u ., R 0.048 for No 1479. In (1) and (2), magnesium is six-coordinate [Mg(N,N'- bidentate )3]; (3)-(6), calcium and strontium are eight-coordinate [M(N,N'- bidentate )4]; in (7), barium is nine-coordinate, one of the en ligands being bridging so that the complex is a single-stranded polymer generated by the 21 screw. Ba-Cl is 3.419(5) Ǻ, Ba -N bidentate en-N are 2.91(2)-2.97(3) Ǻ, and Ba -N monodentate en-N 2.92(1), 3.15(1) Ǻ.
Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. VII. Some Complexes of Group 2 Metal Halides With Aromatic N,N'-Bidentate Ligands
Authors: Skelton BW , Waters AF , White AH
Published: November 2018

Syntheses and room-temperature single-crystal X-ray structural characterizations are recorded for a number of adducts of Group 2 halides with the aromatic N,N′- bidentate ligands L = 2,2'-bipyridine ( bpy ) and 1,10-phenanthroline ( phen ). One adduct of 1 : 1 MX2/L stoichiometry is recorded: [( bpy )Ca(μ-Br)(4/2)](∞ ׀ ∞) (1) is monoclinic, C 2/c, a l7.102(5), b 9.845(1), c 7.600(2) Ǻ, β 107.65(2)°, Z = 4 f.u .; conventional R on #1472; F ׀ at convergence was 0.057 for No 817 independent 'observed' ( I > 3σ(I)) reflections, the compound being a one-dimensional polymer… CaL (μ-Br)2CaL(μ-Br)2…, with six-coordinate calcium, cis-CaN2(μ-Br)4, on a twofold axis. 1 : 2 MX2/L systems have been described for two types of array: [( bpy )2CaI2] (2), orthorhombic, Pnca, a 16.914(4), b 13.80(1), c 9.290(4) Ǻ, Z = 4 f.u .; R 0.039 for No 1738, is discrete mononuclear, containing cis-CaN4I2 six-coordinate calcium, whereas the barium analogue is an infinite one-dimensional polymer, [( bpy )2Ba(μ-I)(4/2)](∞׀ ∞) (3), triclinic, Pī, a 11.318(2), b 11.078(2), c 9.206(4) Ǻ, α 80.87(2), β 77.52(2), γ 87.53(1)°, Z = 2 f.u .; R 0.032 for No 4154, with eight-coordinate (N2)2Ba(μ-I)4. The perchlorate analogue, [( bpy )2Ba(μ-OClO2O)(4/2)](∞ ׀ ∞) (4), although of similar stoichiometry, has a trans-rather than a cis-linked chain; it is monoclinic, P 21/c, a 6.606(2), b 18.661(7), c 19.440(8) Ǻ, β 109.45(4)°, Z = 4 f.u .; R 0.044 for No 4060, with μ-I replaced by O,O'-ClO4 bridging units and eight-coordinate barium, (N2)2BaO4. The 1 : 3 MX2/L system is represented (as its hemi( bipyridine ) 'solvate') by mononuclear [( bpy )3SrI2].0.5bpy (5), monoclinic, P 21/c, a 20.834(8), b 9.735(4), c 18.460(7) Ǻ, β 114.87(3)°, Z = 4 f.u .; R 0.039 for No 3711, containing eight-coordinate strontium, [(N2)3SrI2]; there
is also an isomorphous calcium/ perchlorate analogue [( bpy )3Ca(OClO3)2].0.5bpy (6), a 21.413(6), b 9.813(4), c 18.659(2) Ǻ, β 115.67(2)°, R 0.057 for No 3090, in which unidentate O-ClO4 ligands replace the iodine about the metal atom. A 1 : 4 adduct is obtained with CaI2/phen; ionic [Ca( phen )4] I2 (7), triclinic, Pī , a 14.703(3), b 13.292(3), c 11.38(1) Ǻ, α 92.78(4), β 96.15(4), γ 105.22(2)°, Z = 2 f.u ., R 0.053 for No 3658, contains eight-coordinate Ca(N2)4 arrays, while the novel 1 : 5 adduct [ Ba ( phen )4] I2.MeCN (8) is triclinic, Pī , a 12.170(6), b 13.760(7), c 18 254(8) Ǻ, α 77.05(9), ,β 71.96(4), γ 70.83(9)°, Z = 2 f.u ., R 0.040 for No 4447, containing 10-coordinate barium, [ Ba (N2)5]. A 1 : 4 adduct formed with BaBr2 is [ BrBa( phen )4] Br.MeOH (9), triclinic, Pī , a 17.748(4), b 17.418(2), c 15.535(7) Ǻ, α 91.63(2), β 100.53(3), γ 115.39(1)°, Z = 4 f.u ., R 0.062 for No 4092, containing nine-coordinate barium, [ BrBa (N2)4].