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Thanks to the versatile vinylogous hexafluoro iso -propyl acrylate molecular platforms, a regio- and enantioselective sulfa-Michael reaction was achieved upon organocatalytic conditions, allowing the subsequent amidation, one-pot oxidation, and Mislow-Bravermann-Evans [2,3]-sigmatropic rearrangement along with a 1,3-chirality transfer, leading eventually to a formal asymmetric 1,6-hydroxylation sequence.

An expeditious route to planar chiral sulfur-based scaffolds has been achieved in two operational steps from cheap and commercial [2.2]paracyclophane hydrocarbon. The sulfur atom was introduced in a specific benzylic position of the [2.2]paracyclophane according to a reductive sulfanylation reaction, which proceeds under two complementary reaction conditions with either the BF 3 ·OEt 2 /Et 3 SiH or TFA/BH 3 ·THF combinations. The study was completed by the development of a highly efficient resolution approach by HPLC.

Pheochromocytoma (PC) and paraganglioma (PGL) are rare neuroendocrine tumors that occur throughout the body from the base of the skull to the pelvis. Sympathetic catecholamine-secreting tumors may be associated with hyperadrenergic symptoms and long-term morbidity if they are untreated. Typically biochemically silent, head and neck PGLs may result in cranial nerve palsies and symptoms due to localized mass effect. Tumors can arise sporadically or as part of an inheritable PC-PGL syndrome. Up to 40% of tumors are recognized to be associated with germline mutations in an increasing array of susceptibility genes, including those that appear to arise sporadically. Most commonly, up to 25% of all PC-PGLs are associated with mutations in one of the succinate dehydrogenase (SDH) enzyme subunit genes. The resulting familial PC-PGL syndrome varies according to the affected enzyme subunit (most commonly SDHB and SDHD mutations) with respect to tumor prevalence, location, age of onset, and risk of malignancy. Patients with SDH enzyme mutations have increased lifetime risk of developing multifocal tumors and malignancy. Early recognition of individuals at high risk, genetic testing, screening of family members, and lifelong surveillance programs are recommended, but not without health, economic, and psychologic implications. Anatomic and functional imaging is key to diagnosis, staging, treatment planning, and lifelong surveillance of these individuals. Radiologists must be aware of the imaging appearance of these varied tumors. © RSNA, 2019.

An unprecedented enantioselective α-functionalization of C4-substituted N-alkoxycarbonyl isoxazolidin-5-ones, readily available platforms from Meldrum's acid derivatives, by N-sulfanylphthalimide (PhthSR) electrophiles was achieved upon an efficient phase-transfer catalytic approach, mediated by a commercial N-spiro quaternary ammonium catalyst. Two catalytic activities of the in situ formed R 4 N + Phth - species were highlighted, the phtalimidate being involved in the anion metathesis event and likely as a Brønsted base. This sequence offers a straightforward access to α,α-disubstituted isoxazolidinones, which turned out to be useful precursors of α-sulfanyl-β 2,2 -amino acid derivatives., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Acyl chloride of N-phthaloyl-(S)-isoleucine is an efficient chiral auxiliary for the resolution of (±)-[2.2]paracyclophane-4-thiol. A preparative protocol, based on the conversion into diastereoisomeric thiolesters and separation by two fractional crystallizations and column chromatography, was developed. Deprotection with LiAlH4 allowed isolation of the individual thiol enantiomers in good yield (∼40%) and high enantiomeric purity (ee >93%). The absolute configurations were determined by comparison of the optical rotation value of the products with literature data and were confirmed by X-ray crystallography.

Chest pain is a common symptom amongst patients presenting to the acute medical unit, and presents a diagnostic challenge. We present the case of a previously healthy 65 year old year old gentleman with chest pain and subsequent vomiting, treated initially as an acute coronary syndrome, despite normal ECG and troponin. Chest radiograph revealed left basal consolidation with an effusion, suggesting pneumonia. The absence of symptoms of respiratory infection along with a normal C-reactive protein level led to further investigation with CT. This revealed evidence of oesophageal rupture (Boerhaave's syndrome). Despite early surgical intervention our patient suffered a number of complications and continues his recovery in hospital three months post presentation.

Kinetic resolution of racemic 4-N,N-dimethylaminomethyl[2.2]paracyclophane with 50% sodium tetrachloropalladate and (R)-N-acetylphenylalanine under basic conditions resulted in the formation of a (S(p))-planar chiral palladacycle (35%, >99% ee). Similarly use of 100 mol% sodium tetrachloropalladate resulted in higher levels of conversion and recovery of (S(p))-4-N,N-dimethylaminomethyl[2.2]paracyclophane (41%, >97% ee)., (This journal is © The Royal Society of Chemistry 2012)

Preliminary results concerning a conceptually novel route to chiral sulfoxides based on the asymmetric alkylation of sulfenate salts with alkyl halides mediated by a chiral phase-transfer catalyst are described. As a representative example, o-anisyl methyl sulfoxide was produced in 96% yield and with an enantiomeric excess of 58% using commercial cinchonidinium derivative 2a., (© 2011 American Chemical Society)

The objectives of this study were to compare the 1-year patency of superficial femoral artery (SFA) stent placement with percutaneous transluminal angioplasty (PTA) alone and to attempt to define the role of stents in arterial occlusive disease. Literature searches of the Embase, Medline, and Cochrane databases identified relevant articles, which were split into two subgroups: those containing case-controlled matches for stenting and PTA and those considering only stent placement. The review conformed to the QUORUM statement. One-year patency rates were 219 of 383 (57%) in the stented group and 319 of 607 (53%) in the PTA group for matched cases (odds ratio 1.206 [95% CI 0.932-1.559; p = .115]). The patency of stents deployed secondarily was 554 of 909 (61%). The combined 1-year patency of primary and secondary SFA stents for matched and unmatched case series was 816 of 1,282 (64%). One-year patency rates following stent placement or PTA alone in well-matched patient groups demonstrated no significant difference. This would suggest that the routine use of primary SFA stenting should be undertaken only in selected cases and should mainly be used in "bailout" situations or for complex lesions where surgery is precluded. However, the studies used displayed a high degree of heterogeneity, and some used stent technology that is now considered obsolete. Ongoing randomized controlled trials will provide a more definitive answer to this important problem.

A straightforward and high-yielding access to various [2.2]paracyclophanes possessing a sulfur-based functional group is reported, the key step being a SEAr reaction mediated by a sulfonium salt. The versatility of the methodology was exemplified by an original application in sulfenate salt chemistry, from which a remarkable chirality transfer was observed.

Aliphatic thiolates were efficiently converted into the corresponding sulfenates by smooth oxidation with trans-(+/-)-2-tert-butyl-3-phenyloxaziridine at room temperature (five examples). Subsequent electrophilic quench with benzyl bromide led to sulfoxides (S-alkylation) in good to moderate yields. Application of the protocol to an aromatic substrate was also successful. This work represents the first valuable example of the use of this poorly active oxidizing agent in synthetic organic chemistry without the need for activating conditions.

[reaction: see text] Aromatic 11C-sulfones were synthesized by S alkylation of lithium arenesulfinates, which are readily available from the corresponding thiols by an oxaziridine-mediated oxidation reaction with [11C]alkyl iodides in THF/H2O (4:1) at 150 degrees C. The radiosyntheses, including purification by HPLC, were completed in an average of 35 min from the end of the bombardment with 55-76% overall radiochemical yields (decay corrected). The described procedure extends the range of accessible labeling methods.

[reaction: see text] A general, efficient, and experimentally simple method for the generation of sulfenate salts has been developed using beta-sulfinylesters as substrates. The process is based on a retro-Michael reaction, initiated by deprotonation at low temperature. Upon treatment with alkyl halides, the liberated sulfenates are subsequently converted into sulfoxides in good to excellent yield. Extension of the methodology to an unprecedented access to nonracemic sulfoxides by introduction of an enantiopure ligand, (-)-sparteine, is also described.

Enethiolates derived from dithioesters were efficiently converted into the corresponding vinyl sulfenates by oxidation with a unique N-sulfonyloxaziridine 1a derived from pinacolone. Subsequent alkylation with alkyl halides led to ketene dithioacetal S-oxides in good to excellent yields., (Copyright 2004 American Chemical Society)