Accessing nitrosocarbonyl compounds with temporal and spatial control via the photoredox oxidation of N-substituted hydroxylamines

Photoredox catalysis is employed to generate highly reactive acylnitroso species from hydroxamic acid derivatives. The conditions are shown to be comparable to a previously developed transition metal aerobic oxidation and are amenable to a range of transformations including Diels-Alder and ene reactions. This unique application of such an approach gives access to temporal and spatial control in nitroso chemistry

International genome-wide meta-analysis identifies new primary biliary cirrhosis risk loci and targetable pathogenic pathways.

Primary biliary cirrhosis (PBC) is a classical autoimmune liver disease for which effective immunomodulatory therapy is lacking. Here we perform meta-analyses of discovery data sets from genome-wide association studies of European subjects (n=2,764 cases and 10,475 controls) followed by validation genotyping in an independent cohort (n=3,716 cases and 4,261 controls). We discover and validate six previously unknown risk loci for PBC (Pcombined<5 × 10(-8)) and used pathway analysis to identify JAK-STAT/IL12/IL27 signalling and cytokine-cytokine pathways, for which relevant therapies exist

Rapid and Stereoselective Synthesis of Spirocyclic Ethers via the Intramolecular Piancatelli Rearrangement

The first example of a Piancatelli rearrangement of alcohols is demonstrated utilizing dysprosium(III) triflate as a catalyst to access oxaspirocycles in a highly diastereoselective manner. The cascade reaction constructs the spirocyclic ether ring system and the tertiary stereocenter in a single operation and is experimentally easy to perform

Two Approaches to the Aromatic Core of the Aminonaphthoquinone Antibiotics

Two complementary approaches are presented for the synthesis of the quinone chromophores of the naphthoquinone ansamycins and related natural products. The first involves the use of an improved protocol for the manganese­(III) acetate mediated cyclization of 5-aryl-1,3-dicarbonyl compounds to β-naphthols, leading to the simple, scalable preparation of building blocks suitable for the synthesis of naturally occurring aminonaphthoquinones. The second approach involves the Diels–Alder reaction of a series of new, ester-containing Danishefsky-type dienes with <i>N</i>-protected aminobenzoquinones to allow more expeditious access to similar intermediates

Two Approaches to the Aromatic Core of the Aminonaphthoquinone Antibiotics

Two complementary approaches are presented for the synthesis of the quinone chromophores of the naphthoquinone ansamycins and related natural products. The first involves the use of an improved protocol for the manganese­(III) acetate mediated cyclization of 5-aryl-1,3-dicarbonyl compounds to β-naphthols, leading to the simple, scalable preparation of building blocks suitable for the synthesis of naturally occurring aminonaphthoquinones. The second approach involves the Diels–Alder reaction of a series of new, ester-containing Danishefsky-type dienes with <i>N</i>-protected aminobenzoquinones to allow more expeditious access to similar intermediates

Cascade rearrangement of furylcarbinols with hydroxylamines: practical access to densely functionalized cyclopentane derivatives.

This article describes the aza-Piancatelli rearrangement with hydroxylamines to 4-aminocyclopentenones and subsequent transformations that highlight the versatility of the cyclopentene scaffold and the value of the hydroxylamine nucleophile in this transformation

Cascade rearrangement of furylcarbinols with hydroxylamines: practical access to densely functionalized cyclopentane derivatives.

This article describes the aza-Piancatelli rearrangement with hydroxylamines to 4-aminocyclopentenones and subsequent transformations that highlight the versatility of the cyclopentene scaffold and the value of the hydroxylamine nucleophile in this transformation

ChemInform Abstract: Cascade Rearrangement of Furylcarbinols with Hydroxylamines: Practical Access to Densely Functionalized Cyclopentane Derivatives.

This article describes the aza-Piancatelli rearrangement with hydroxylamines to 4-aminocyclopentenones and subsequent transformations that highlight the versatility of the cyclopentene scaffold and the value of the hydroxylamine nucleophile in this transformation

Importance of off-cycle species in the acid-catalyzed aza-Piancatelli rearrangement.

The observed rate of reaction in the dysprosium triflate catalyzed aza-Piancatelli rearrangement is controlled by a key off-cycle binding between aniline and catalyst. Deconvoluting the role of these ancillary species greatly broadens our understanding of factors affecting the productive catalytic pathway. We demonstrate that the rate of reaction is controlled by initial competitive binding between the furylcarbinol and nitrogen nucleophile using either a Brønsted or Lewis acid catalyst and that the resulting rearrangement proceeds without involving the Brønsted and Lewis acid catalyst. This shows conclusively that the rate-controlling step and selectivity of reaction are decoupled