We report maps of the concentrations of H, Si, Cl, K, Fe, and Th as determined by the Gamma Ray Spectrometer (GRS) on board the 2001 Mars Odyssey Mission for ±∼45° latitudes. The procedures by which ...the spectra are processed to yield quantitative concentrations are described in detail. The concentrations of elements determined over the locations of the various Mars landers generally agree well with the lander values except for Fe, although the mean of the GRS Fe data agrees well with that of Martian meteorites. The water‐equivalent concentration of hydrogen by mass varies from about 1.5% to 7.5% (by mass) with the most enriched areas being near Apollinaris Patera and Arabia Terra. Cl shows a distribution similar to H over the surface except that the Cl content over Medusae Fossae is much greater than elsewhere. The map of Fe shows enrichment in the northern lowlands versus the southern highlands. Silicon shows only very modest variation over the surface with mass fractions ranging from 19% to 22% over most of the planet, though a significant depletion in Si is noted in a region west of Tharsis Montes and Olympus Mons where the Si content is as low as 18%. K and Th show a very similar pattern with depletions associated with young volcanic deposits and enrichments associated with the TES Surface Type‐2 material. It is noted that there appears to be no evidence of significant globally distributed thick dust deposits of uniform composition.
Abstract
The dearomative spirocyclisation of benzisoxazoles through a radical chain mechanism is described. Densely functionalised spirocycles were prepared in high yields by reacting ...benzisoxazole‐tethered ynones with aryl thiols in 1,2‐dichloroethane (DCE) at 60 °C. The identification of stabilising three‐electron interactions was key to the development of this new radical cascade reaction. The obtained spirocyclic products were converted into other spirocyclic scaffolds through a two‐step hydrogenolysis‐cyclisation sequence.
To evaluate the efficacy and safety of a selective serotonin reuptake inhibitor (SSRI) and a serotonin and norepinephrine reuptake inhibitor (SNRI) in the treatment of depression in Parkinson disease ...(PD).
A total of 115 subjects with PD were enrolled at 20 sites. Subjects were randomized to receive an SSRI (paroxetine; n = 42), an SNRI (venlafaxine extended release XR; n = 34), or placebo (n = 39). Subjects met DSM-IV criteria for a depressive disorder, or operationally defined subsyndromal depression, and scored >12 on the first 17 items of the Hamilton Rating Scale for Depression (HAM-D). Subjects were followed for 12 weeks (6-week dosage adjustment, 6-week maintenance). Maximum daily dosages were 40 mg for paroxetine and 225 mg for venlafaxine XR. The primary outcome measure was change in the HAM-D score from baseline to week 12.
Treatment effects (relative to placebo), expressed as mean 12-week reductions in HAM-D score, were 6.2 points (97.5% confidence interval CI 2.2 to 10.3, p = 0.0007) in the paroxetine group and 4.2 points (97.5% CI 0.1 to 8.4, p = 0.02) in the venlafaxine XR group. No treatment effects were seen on motor function.
Both paroxetine and venlafaxine XR significantly improved depression in subjects with PD. Both medications were generally safe and well tolerated and did not worsen motor function.
This study provides Class I evidence that paroxetine and venlafaxine XR are effective in treating depression in patients with PD.
A copper(II)‐catalysed approach to oxindoles, thio‐oxindoles, 3,4‐dihydro‐1H‐quinolin‐2‐ones, and 1,2,3,4‐tetrahydroquinolines via formal CH, ArH coupling is described. In a new variant, copper(II) ...2‐ethylhexanoate has been identified as an inexpensive and efficient catalyst for this transformation, which utilises atmospheric oxygen as the re‐oxidant.
Copper(II) 2‐ethylhexanoate: The synthesis of oxindoles, thio‐oxindoles, 3,4‐dihydro‐1H‐quinolin‐2‐ones, and 1,2,3,4‐tetrahydroquinolines from linear precursors by direct CH, ArH coupling by using a single copper catalyst is reported (see scheme; DIPEA=diisopropylethylamine, EWG=electron‐withdrawing group). The cyclisations are simple to perform, run open to the air, are moisture insensitive, and use an inexpensive catalyst.
An asymmetric decarboxylative palladium-catalyzed allylation of alkyl- and aryl-substituted oxindoles has been developed, enabling the installation of an all-carbon quaternary chiral center at the ...oxindole 3-position in excellent yields and good to excellent enantioselectivity. An intriguing substrate-dependent reversal in stereoselectivity has been observed, whereby the size of the substituent determines the facial selectivity in the allylation step.
A one-pot C–H insertion/olefination sequence for the conversion of α-diazo-α-(dialkoxyphosphoryl)acetates into α-alkylidene-γ-butyrolactones is reported. The key C–H insertion process is ...achieved using a catalytic amount of a dirhodium carboxylate catalyst, using operationally simple conditions. The size and electronic properties of the attached substituents were found to influence the regio- and diastereoselectivity of the process. The utility of the process is demonstrated by the synthesis of a known Staphylococcus aureus (MRSA) virulence inhibitor.
The acid test? The synthetic route to the title compound features a Z‐selective ring‐closing metathesis reaction and an E‐selective tandem intramolecular Michael addition/alkene migration sequence as ...the key transformations. The stereochemical configuration of the product was reassigned based on NMR studies.
The synthesis of the two proposed structures of macrocyclic marine natural product ‘upenamide is reported. The key step utilizes direct imine acylation (DIA) with a protected β-hydroxy acid to ...construct the key tricyclic ABC ring system. The macrocyclization was completed in the final step using a Stille cross-coupling reaction.
A grand route to grandisines: A method for the conversion of 6‐acyl cyclohexenones into 2,6‐disubstituted 2,3,4,5‐tetrahydropyridines and, after diastereoselective reduction, 2,6‐syn‐disubstituted ...piperidines has been developed. The scope of this process is outlined by the synthesis of cis‐2‐methoxycarbonylmethyl‐6‐pentylpiperidine and the first total synthesis of the Elaeocarpus‐derived alkaloid (−)‐grandisine G (see scheme).
Objective. RA has a substantial impact on both patients and healthcare systems. Our objective is to advance the understanding of modern management principles in light of recent evidence concerning ...the condition's diagnosis and treatment. Methods. A group of practicing UK rheumatologists formulated contemporary management principles and clinical practice recommendations concerning both diagnosis and treatment. Areas of clinical uncertainty were documented, leading to research recommendations. Results. A fundamental concept governing treatment of RA is minimization of cumulative inflammation, referred to as the inflammation–time area under the curve (AUC). To achieve this, four core principles of management were identified: (i) detect and refer patients early, even if the diagnosis is uncertain: patients should be referred at the first suspicion of persistent inflammatory polyarthritis and rheumatology departments should provide rapid access to a diagnostic and prognostic service; (ii) treat RA immediately: optimizing outcomes with conventional DMARDs and biologics requires that effective treatment be started early—ideally within 3 months of symptom onset; (iii) tight control of inflammation in RA improves outcome: frequent assessments and an objective protocol should be used to make treatment changes that maintain low-disease activity/remission at an agreed target; (iv) consider the risk–benefit ratio and tailor treatment to each patient: differing patient, disease and drug characteristics require long-term monitoring of risks and benefits with adaptations of treatments to suit individual circumstances. Conclusion. These principles focus on effective control of the inflammatory process in RA, but optimal uptake may require changes in service provision to accommodate appropriate care pathways.
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