Single-Step Synthesis of γ-Ketoacids through a Photoredox-Catalyzed Dual Decarboxylative Coupling of α-Oxo Acids and Maleic Anhydrides.

A photocatalytic methodology for the single step synthesis of γ-ketoacids from α-ketoacids has been developed. This method employs maleic anhydrides as traceless synthetic equivalents of acrylic acids, achieving a selective cross-coupling via a dual decarboxylative strategy, where molecular CO2 is released as the only waste byproduct. The method has also been expanded to incorporate a highly regioselective, 3-component coupling with various alcohols to access functionalized γ-ketoesters.

Indian College of Radiology and Imaging (ICRI) Consensus Guidelines for the Early Management of Patients with Acute Ischemic Stroke: Imaging and Intervention.

The medical science has witnessed significant change in the management of acute stroke patients as a result of recent advances in the field of stroke imaging and endovascular mechanical thrombectomy in addition to intravenous thrombolysis and optimization of stroke services in balance with available resources. Despite initial negative trials, we witnessed the publication of five multicenter randomized clinical trials showing superiority of the endovascular approach over standard medical management in patients with large vessel occlusion. The aim of this study is to provide comprehensive set of evidence-based recommendations regarding imaging and endovascular interventions in acute ischemic stroke patients.

Formal α-Allylation of Primary Amines by a Dearomative, Palladium-Catalyzed Umpolung Allylation of N-(Aryloxy)imines.

N-(Aryloxy)imines, readily accessible by condensation/tautomerization of (pseudo)benzylic primary amines and 2,6-di-tert-butyl-1,4-benzoquinone, undergo efficient allylation to afford a wide range of homoallylic primary amines following hydrolytic workup. Deprotonation of N-(aryloxy)imines generates a delocalized 2-azaallyl anion-type nucleophile that engages in dearomative C-C bond-forming reactions with allylpalladium(II) electrophiles generated from allylic tert-butyl carbonates. This reactivity umpolung enables the formal α-allylation of (pseudo)benzylic primary amines. Mechanistic studies reveal that the apparent regioselectivity of the desired bond-forming event is a convergent process that is initiated by unselective allylation of N-(aryloxy)imines to give several regioisomeric species, which subsequently rearrange via stepwise [1,3]- or concerted [3,3]-sigmatropic shifts, ultimately converging to provide the desired regioisomer of the amine products.

Blindness Following Carotid Artery Stenting Due to Ocular Hyperperfusion - Report and Review of Literature.

Cerebral hyperperfusion syndrome is a well-recognised phenomenon following carotid revascularisation. It is defined as cerebral blood flow increase of more than 100% of the baseline. A similar phenomenon can occur in the eye and maybe termed as ocular hyperperfusion syndrome. We present a 65-year-old male who developed an ipsilateral red eye with visual loss following carotid artery stenting. There was a past history of recurrent right middle cereberal artery (MCA) territory embolic infarcts and recurrent trasient episodes of vision loss in the right eye. Flow reversal was noted in the ophthalmic artery on Transcranial doppler (TCD). Digital subtraction angiography (DSA) showed more than 95% stenosis in right internal carotid artery (ICA) ostium and completely occluded left ICA. Following carotid artery, stenting patient developed severe headache and right eye pain along with vision loss despite intensive blood pressure monitoring and control. NCCT head showed mild right cortical SAH and the intra-ocular pressure (IOP) in the right eye was high. It was hypopthesised that aqueous over production due to neovascularity secondary to chronic ocular ischemia, lack of outflow and sudden change in ocular hemodynamics post stenting was the pathogenic mechanism. The patient was commenced on measures to reduce aqueous production along with strict blood pressure control. Prestenting evalvation for chronic ocular ischemia with tanscranial dopplar and angiographic flow reversal in ophthalmic artery, fluorescein angiography to look for watershed zones and slit lamp for neovascularity and angle closure can help in identifing high-risk patients, particularly in patients with bilateral carotid artery disease.

Quinone-catalyzed oxidative deformylation: synthesis of imines from amino alcohols.

A new method for imine synthesis by way of quinone-catalyzed oxidative deformylation of 1,2-amino alcohols is reported. A wide range of readily accessible amino alcohols and primary amines can be reacted to provide N-protected imine products. The methodology presented provides a novel organocatalytic approach for imine synthesis and demonstrates the synthetic versatility of quinone-catalyzed oxidative C-C bond cleavage.