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Homoleptic uranium(IV) amidate complexes have been synthesized and applied as single-source molecular precursors for the chemical vapor deposition of UO2 thin films. These precursors decompose by alkene elimination to give highly crystalline phase-pure UO2 films with an unusual branched heterostructure.

Vascular Ehlers Danlos syndrome (vEDS) is an uncommon genetic disorders characterized by arterial aneurysm, dissection and rupture, bowel rupture, and rupture of the gravid uterus. The frequency is estimated as 1/50,000-1/200,000 and results from pathogenic variants in COL3A1, which encodes the chains of type III procollagen, a major protein in vessel walls and hollow organs. Initial diagnosis depends on the recognitions of clinical features, including family history. Management is complex and requires multiple specialists who can respond to and manage the major complications. A summary of recommendations for management include: Identify causative variants in COL3A1 prior to application of diagnosis, modulate life style to minimize injury, risk of vessel/organ rupture, identify and create care team, provide individual plans for emergency care ("vascular EDS passport") with diagnosis and management plan for use when traveling, centralize management at centers of excellence (experience) when feasible, maintain blood pressure in the normal range and treat hypertension aggressively, surveillance of vascular tree by doppler ultrasound, CTA (low radiation alternatives) or MRA if feasible on an annual basis. These recommendations represent a consensus of an international group of specialists with a broad aggregate experience in the care of individuals with vascular EDS that will need to be assessed on a regular basis as new information develops. © 2017 Wiley Periodicals, Inc.

Keratitis-ichthyosis-deafness (KID) syndrome is a rare ectodermal dysplasia, characterized mainly by the presence of hyperkeratotic skin lesions, neurosensory hearing loss, and vascularizing keratitis. Most mutations that have been discovered as a cause of KID syndrome are autosomal dominant, found in exon 2 of the Connexin (Cx) 26 gene. A G12R (p.Gly12Arg) is a GJB2 mutation reported in only two patients with KID syndrome to date. This article describes a patient with the G12R mutation and KID syndrome with interesting additional features, which include a porokeratotic eccrine ostial and dermal duct nevus, follicular occlusion triad, and unusual persistent oral mucosal papules. We compare this patient’s phenotype with the only two other patients described with the same (G12R) mutation. The phenotypic heterogeneity of KID syndrome, inexplicable according to our current understanding of these proteins, speaks to the complexity of the connexin system and its overlapping expression patterns in different tissues.

Incidence of Bordetella pertussis infection among adults has risen significantly throughout the United States, but pertussis is not often considered in the differential diagnosis of chronic cough in adults. The authors hypothesized that serum IgG testing can establish a diagnosis of pertussis infection late in disease presentation when cultures and polymerase chain reaction (PCR) testing are not reliable.Case series with chart review.Tertiary care hospital.Institutional B pertussis serum IgG and PCR tests were reviewed since 2007. Clinical factors assessed included vaccination history, duration and severity of cough, and general medical history.Forty-eight patients had B pertussis fimbrial agglutinogen IgG levels tested since 2007, with a significant increase in positive IgG tests (27 IU/mL, 3 times the upper limit of normal) since fall 2009. Nineteen patients (39.5%) met IgG criteria for likely recent pertussis infection. Six IgG-positive patients also had PCR swab testing performed, with 50% positive for B pertussis. IgG values were similar for patients with positive or negative B pertussis PCR testing with positive IgG titers. IgG-positive patients were much more likely to have posttussive syncope. Recent vaccination for pertussis within the 3 years prior to IgG testing did not significantly increase IgG levels.One-time B pertussis serum IgG testing and patient history can establish a likely diagnosis of recent pertussis infection in the adult patient with chronic cough late in disease presentation when PCR testing is often negative. Pertussis should be considered in the differential diagnosis of all patients with chronic cough.

We have traditionally viewed continuity of care with a particular intern as important for high-quality inpatient care, but this continuity is difficult to achieve. As we move to a model of team rather than individual continuity, information transfers between team members become critical. When discontinuity between the primary team and a cross-covering team occurs, this informational continuity is managed through formal handoffs. Accordingly, there has been ample research on handoffs between different teams, but there has been little published literature to date to describe handoffs between members of the same team. Therefore, we set out (1) to learn how interns view intrateam handoffs and (2) to identify intern-perceived problems with intrateam handoffs.

A method for the synthesis and quality control of compound collections containing reactive thiol functions was developed. Such libraries form the basis for the construction of chemical microarrays to be used in fragment-based screening. Amino-modified polymer membranes fixed into the wells of microtiter plates were used as the solid phase for the nanomole-scale synthesis of a thiol-tagged small molecule library using a spatial one-compound/one-well strategy. A thiolselective Liquid Chromatography-Mass Spectroscopy (LC-MS) protocol of each compound before attachment to the microarray surface was established, allowing an exact determination of compound purity and concentration. The established synthesis and quality control method is an important prerequisite for an accurate read-out of the array compound-target interaction data, and simplifies the usage of small molecule microarrays for low affinity screening.

Methyl β-D-arabinopyranoside (1), phenyl 1-thio-β-D-galactopyranoside (3), methyl β-L-fucopyranoside (7), methyl β-L-fucopyranoside (9), 1,6-anhydro-β-D-galactopyranoside (D-galactosan; 11), and 1,6-anhydro-β-D-mannopyranoside (D-mannosan; 14) were stereospecifically converted in moderate up to good yields into methyl 4-O-cyclohexylcarbamoyl-2,3-O-(2,2,2-trichloroethylidene)-β-D-lyxopyranoside (2), phenyl 4-(9-cyclohexyIcarbamoyl-6-O-formyl-2,3-O-(2,2,2-trichloroethylidene)-1-thio-β-D-gulopyranoside (4) / phenyl 4-O-cyclohexylcarbamoyl-2,3-O-(2,2,2-trichloroethylidene)-1-thio-β-D-gulopyraoside (5), methyl 4-O-cyclohexylcarbamoyl-2,3-O-(2,2,2-trichloroethylidene)-6-deoxy-α-L-gulopyranoside (8), methyl 2,3-O-(2,2,2-trichloroethylidene)-4-O-cyclohexylcarbamoyl-6-deoxy-β-L-gulopyranoside (10), 1,6-anhydro-4-O-cyclohexyl-carbamoyl-2,3-O-(2,2,2-trichloroethylidene)-β-D-gulopyranoside (12), and 1,6-anhydro-2-O-cyclohexylcarbamoyl-3,4-O-(2,2,2-trichloroethylidene)-β-D-altropyranoside (15), respectively, ...

The disaccharides benzyl 4,6-O- benzylidene -2-O-α- d - mannopyranosyl -β- d - glucopyranoside (2), 6-O-β- d - galactopyranosyl -1,2:3,4- di -O- isopropylidene -α- d - galactopyranose (4), and phenyl 4-O-β- d - galactopyranosyl -1- thio -β- d - glucopyranoside (7) were selectively acetalated with chloral-dicyclohexylcarbodiimide in a nonclassical pathway. During acetalation, the d -mannopyranosyl moiety of the disaccharide 2 and the unprotected β- d -galactopyranosyl moieties of 4 and 7 were epimerized at their 3-positions, generating d -altro- and d -gulo-pyranosyl moieties, respectively.

The homologous 1-iodo-perfluoroalkanes 1a-1c and α,ω-dibromo-perfluoroalkanes 4a, 4b were carbonylated with DMF in the presence of Al/SnCl 2 Al/PbBr 2 under sonication in a short reaction time. The hydrated aldehydes 2a-2c and 5a, 5b respectively were obtained in good yields allowing dehydration to 3a-3c and 6a, 6b . Some of the fluorinated aldehydes were selected as substrates in a Wittig-Horner olefination assisted by ultrasound and in non-conventional acetalations of methyl α- l -rhamnopyranoside ( 9 ). Thus, ( E )-1-perfluorooctyl-2-phenylsulphonyl-ethene ( 8 ) was prepared from 3c and the phosphonate 7 by Wittig-Horner synthesis. Acetalations of 9 were carried out with the aldehydes ( 3a, 3b, 6a ), hydrated aldehydes ( 2a, 2b ), and the aldehyde hemiacetal 12 respectively, in the presence of dicyclohexylcarbodiimide (DCC). In all cases, a selective epimerization was observed at the C-atom 3 of the monosaccharide, i.e. polyfluoroalkylidenated 6-deoxy-α- l -altropyranosides 10,11,13 , and 14 were obtained.

The acyclic and cyclic allylic tert -butyl sulfones 3 , ent - 3 , 11a , 11b and 15a–c of 89–98% ee were synthesized in 40–92% yield by a Pd-catalyzed reaction of the respective allylic acetates and carbonates rac - 1a , rac - 1b , rac - 10a , rac - 10b and rac - 14a–c with LiO 2 S t -Bu in the presence of the chiral ligands 2a , ent - 2b and 12 . Formation of the n -butyl sulfones 13a and 13b of 95% ee was observed. Reactions of rac - 1a and 1b / ent - 1b with LiO 2 S t -Bu in the presence of 2a and ent - 2b , respectively, in THF under heterogeneous conditions were accompanied by a kinetic resolution of the allylic substrates. The faster reacting allylic substrate and the preferentially formed sulfone had the same absolute configuration. The allylic tert -butyl sulfide 17 of 92% ee was obtained in 63% yield by the Pd-catalyzed reaction of rac - 1b with Me 3 SiS t -Bu in the presence of ent - 2b .

Cyclic and acyclic allylic S-p-chlorophenyl, S-2-pyridyl and S-2-pyrimidyl sulfides of 50–96% ee have been obtained in 24–87% yield through reaction of the corresponding racemic carbonates with p-chlorothiophenol, 2-mercaptopyridine and 2-mercaptopyrimidine, respectively, mediated by a complex generated in situ from Pd2(dba)3·CHCl3 and the Trost ligand.

We describe the highly selective palladium catalyzed kinetic resolutions of the racemic cyclic allylic carbonates rac-1 a-c and racemic acyclic allylic carbonates rac-3 aa and rac-3 ba through reaction with tert-butylsulfinate, tolylsulfinate, phenylsulfinate anions and 2-pyrimidinethiol by using N,N'-(1R,2R)-1,2-cyclohexanediylbis[2-(diphenylphosphino)-benzamide] (BPA) as ligand. Selectivities are expressed in yields and ee values of recovered substrate and product and in selectivity factors S. The reaction of the cyclohexenyl carbonate 1 a (>/=99 % ee) with 2-pyrimidinethiol in the presence of BPA was shown to exhibit, under the conditions used, an overall pseudo-zero order kinetics in regard to the allylic substrate. Also described are the highly selective palladium catalyzed asymmetric syntheses of the cyclic and acyclic allylic tert-butylsulfones 2 aa, 2 b, 2 c, 2 d and 4 a-c, respectively, and of the cyclic and acyclic allylic 2-pyrimidyl-, 2-pyridyl-, and 4-chlorophenylsulfides 5 aa, 5 b, 5 ab, 6 aa-ac, 6 ba and 6 bb, respectively, from the corresponding racemic carbonates and sulfinate anions and thiols, respectively, in the presence of BPA. Synthesis of the E-configured allylic sulfides 6 aa, 6 ab, 6 ac and 6 bb was accompanied by the formation of minor amounts of the corresponding Z isomers. The analogous synthesis of allylic tert-butylsulfides from allylic carbonates and tert-butylthiol by using BPA could not be achieved. Reaction of the cyclopentenyl esters rac-1 da and rac-1 db with 2-pyrimidinethiol gave the allylic sulfide 5 c having only a low ee value. Similar results were obtained in the case of the reaction of the cyclohexenyl carbonate rac-1 a and of the acyclic carbonates rac-3 aa and rac-3 ba with 2-pyridinethiol and lead to the formation of the sulfides 5 ab, 6 ab, and 6 bb, respectively. The low ee values may be ascribed to the operating of a "memory effect", that is, both enantiomers of the substrate give the substitution product with different enantioselectivities. However, in the reaction of the racemic carbonate rac-1 a as well as of the highly enriched enantiomers 1 a (>/=99 % ee) and ent-1 a (>/=99 % ee) with 2-pyrimidinethiol the ee values of the substrates and the substitution product remained constant until complete conversion. Similar results were obtained in the reaction of the cyclic carbonates rac-1 a, ent-1 a (>/=99 % ee) and ent-1 c (>/=99 % ee) with lithium tert-butylsulfinate. Thus, in the case of rac-1 a and 2-pyrimidinthiol and tert-butylsulfinate anion as nucleophiles the enantioselectivity of the substitution step is, under the conditions used, independent of the chirality of the substrate; this shows that no "memory effect" is operating in this case. Hydrolysis of the carbonates ent-1 a-c, ent-3 aa and ent-3 ba, which were obtained through kinetic resolution, afforded the enantiomerically highly enriched cyclic allylic alcohols 9 a-c (>/=99 % ee) and acyclic allylic alcohols 10 a (>/=99 % ee) and 10 b (99 % ee), respectively.

Recent advances in structural and conformational analysis of fluorinated carbohydrates by NMR spectroscopy are reviewed. Characteristic 1 H, 13 C, and 19 F NMR chemical shifts and coupling constants for selected examples are given and the spectral data of a series of fluorinated carbohydrates were collected in continuation of the review of Csuk and Glanzer [ Adv. Carbohydr. Chem. Biochem ., 46 (1988) 73–177].

S-Athyl-S-methyl-sulfodiimid, CH3(C2H5)S(NH)2 (1), und N.S.S-Trimethyl-sulfodiimid, (CH3)2S(NCH3)NH (2), tauschen in D2O ihre zum S-Atom α-standigen Methylprotonen gegen Deuterium aus. Die Geschwindigkeitskonstanten und die Aktivierungsenergien werden mit Hilfe der Protonenresonanz bestimmt. Die S.S-Dimethylverbindung folgt dem Bronstedschen Katalysegesetz. Hydrogen-Deuterium Exchange in S-Ethyl-S-methylsulfodiimide and in N.S.S-Trimethylsulfodiimide S-Ethyl-S-methylsulfodiimid, CH3(C2H5)S(NH)2 (1), and N.S.S-Trimethylsulfodiimide, (CH3)2S(NCH3)NH (2), exchange in D2O-solution the protons of the S-methyl groups with deuterium. The rates of reaction and activation energies were determined by n.m.r. spectroscopy. The S.S-dimethyl compound follows the Bronsted catalysis law.