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Heterocyclic nonacetamide ligands are used as positron emission tomography (PET) imaging agents of the synaptic vesicle glycoprotein 2A (SV2A), with potential applications in the diagnosis of various neuropsychiatric diseases. To date, the main synthetic strategy to access these optically active compounds has involved the racemic synthesis of a late-stage intermediate followed by the separation of the enantiomers. Here, we describe the use of iminium organocatalysis for the asymmetric synthesis of SynVesT-1, an important PET imaging agent of SV2A. The key step involved the conjugate addition of nitromethane with a cinnamaldehyde in the presence of the Jørgensen-Hayashi catalyst using the Merck dual acid cocatalyst system. Pinnick-type oxidation and esterification of the adduct was then followed by chemoselective nitro group reduction and cyclization using nickel borate. N -Alkylation of the resulting lactam then completed the seven-step synthesis of SynVesT-1. This approach was amenable for the synthesis of an organotin analogue, which following copper(II)-mediated fluoro-destannylation allowed rapid access to [ 18 F]SynVesT-1.

A mild and inexpensive method for direct hydrodecarboxylation of aliphatic carboxylic acids has been developed. The reaction does not require metals, light, or catalysts, rendering the protocol operationally simple, easy to scale, and more sustainable. Crucially, no additional H atom source is required in most cases, while a broad substrate scope and functional group tolerance are observed.

The arylboronic acid catalyzed dehydrative C -alkylation of 1,3-diketones and 1,3-ketoesters using secondary benzylic alcohols as the electrophile is reported, forming new C-C bonds (19 examples, up to 98% yield) with the release of water as the only byproduct. The process is also applicable to the allylation of benzylic alcohols using allyltrimethylsilane as the nucleophile (12 examples, up to 96% yield).

Gold-catalyzed hydroarylation of unactivated alkynes with indoles have previously been reported to proceed with double indole addition to produce symmetrical bis(indolyl)methanes (BIMs). We demonstrate for the first time that the selectivity of the gold-catalyzed reaction can be fully switched to allow for isolation of the vinylindole products instead. Furthermore, this selective reaction can be utilized to synthesize the more difficult to access unsymmetrical BIMs from readily available starting materials.

The use of copper catalysis with visible light photoredox catalysis in a cooperative fashion has recently emerged as a versatile means of developing new C-C bond forming reactions. In this work, dual copper and photoredox catalysis is exploited to effect C(sp2)-C(sp3) cross-couplings between aryl boronic acids and benzyl bromides.

A combination of pentafluorophenylboronic acid and oxalic acid catalyses the dehydrative substitution of benzylic alcohols with a second alcohol to form new C-O bonds. This method has been applied to the intermolecular substitution of benzylic alcohols to form symmetrical ethers, intramolecular cyclisations of diols to form aryl-substituted tetrahydrofuran and tetrahydropyran derivatives, and intermolecular crossed-etherification reactions between two different alcohols. Mechanistic control experiments have identified a potential catalytic intermediate formed between the aryl boronic acid and oxalic acid., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

One eyelid of each of three Macaca nemestrina monkeys was sutured shut at 3 weeks of age. One animal had the central 10 degrees of the open eye retina lesioned at 3 weeks of age (EL1), a second at 9 months of age (LL1), and the third had no lesion (MD1). After a reverse suture at 9 months of age, the deprived eye was tested for grating acuity, visual behavior, and visual field. EL1 tested positively on all behavioral tasks by 1 month and showed good visual ability to negotiate a playroom but never performed better than 20/1,250 on grating acuity. MD1 showed little visual behavior in the playroom but tested at 20/400 acuity. LL1 rapidly recovered all aspects of visual behavior and tested at 20/80 visual acuity. Perimetry shows that LL1 and EL1 respond mainly in the central portion of the deprived eye visual field but not to the periphery or the monocular segment. We conclude that removal of the open eye retina after the critical period allows much visual recovery by the deprived eye but that removal of the open eye retina within the critical period does not prevent many of the effects of monocular deprivation.

A 9-year-old boy had a unilateral ocular lesion characterized by a broadly elevated mass at the level of the retinal pigment epithelium. The mass showed hyperpigmented borders, overlying retinal constracture, retinal vessel tortuosity, and vitreous condensations. Electrophysiologic testing revealed an abnormal electrooculogram.

A 21-year-old woman with pars planitis was treated with a subtenon's depot corticosteroid injection that was complicated by the appearance of the corticosteroid suspension within the choroidal vasculature. White, flocculent material was observed in the anterior chamber and 24 hours later this settled on the iris surface. Similar material was located in the major choroidal vessels. Two months after the incident, the choroid was normal appearing but the pars planitis was unchanged.

The rapid development of suppurative reaction in response to a copper-containing intraocular foreign body disposes the eye to a poor prognosis. An intraocular brass foreign body case involving cornea, iris, lens, vitreous and retina was satisfactorily managed by early foreign body removal and corneal transplantation followed by scleral buckling for retinal detachment. Early intervention is advocated as alternative management with expectation of improvement in the prognosis for recovery of useful visual function.

A previously healthy 44-year-old man died three weeks after the simultaneous onset of encephalitis and retinitis. Fundus changes were bilateral and included papillitis, rapidly progressive central retinal vein obstruction, and massive exudative retinal detachment. A 16-fold rise in herpesvirus hominis antibodies occured between the 10th and 20th days of illness. At autopsy, the brain showed changes characteristic of herpetic encephalitis, and cultures of the brain yielded Herpesvirus hominis type I. Intranuclear inclusion bodies typical of those produced by Herpesvirus were found by light microscopy in brain, optic nerves, retina, and choroid. Herpesvirus particles were found by electron microscopy in brain, optic nerve, and retina.