2 research outputs found
Domino HydrogenationâReductive Amination of Phenols, a Simple Process To Access Substituted Cyclohexylamines
Phenols can be efficiently
reduced by sodium formate and Pd/C as
the catalyst in water and in the presence of amines to give the corresponding
cyclohexylamines. This reaction works at rt for 12 h or at 60 °C
under microwave dielectric heating for 20 min. With the exception
of aniline, primary, secondary amines, amino alcohols, and even amino
acids can be used as nucleophiles. The reductive process is based
on a sustainable hydrogen source and a catalyst that can be efficiently
recovered and reused. The protocol was developed into a continuous-flow
production of cyclohexylamines in gram scale achieving very efficient
preliminary results (TON 32.7 and TOF 5.45 h<sup>â1</sup>)
Neutrophil-mediated mechanisms of damage and in vitro protective effect of colchicine in non-vascular Behçet's syndrome
Behçetâs syndrome (BS) is a systemic vasculitis with several clinical manifestations. Neutrophil hyperactivation mediates vascular BS pathogenesis, via both a massive reactive oxygen species (ROS) production and neutrophil extracellular traps (NETs) release. Here, we investigated neutrophilâmediated mechanisms of damage in nonâvascular BS manifestations and explored the inâvitro effects of colchicine in counteracting these mechanisms. NETs and intracellular ROS production was assessed in blood samples from 80 BS patients (46 with active nonâvascular BS, 34 with inactive disease) and 80 healthy controls. Moreover, isolated neutrophils were incubated for 1 h with an oxidating agent [2,2â˛âazobis (2âamidinopropane) dihydrochloride; 250 nM] and the ability of pure colchicine pretreatment (100 ng/ml) to counteract oxidationâinduced damage was assessed. Patients with active nonâvascular BS showed remarkably increased NET levels [21.2, interquartile range (IQR) = 18.3â25.9 mU/ml] compared to patients with inactive disease (16.8, IQR = 13.3â20.2 mU/ml) and to controls (7.1, IQR = 5.1â8.7 mU/ml, p < 0.001]. Also, intracellular ROS tended to increase in active BS, although not significantly. In active nonâvascular BS, NETs correlated with neutrophil ROS production (p < 0.001) and were particularly increased in patients with active mucosal (p < 0.001), articular (p = 0.004) and gastrointestinal symptoms (p = 0.006). In isolated neutrophils, colchicine significantly reduced oxidationâinduced NET production and cell apoptosis, although not via an antiâoxidant activity. Neutrophilâmediated mechanisms might be directly involved in nonâvascular BS, and NETs, more than ROS, might drive the pathogenesis of mucosal, articular and intestinal manifestations. Colchicine might be effective in counteracting neutrophilsâmediated damage in BS, although further studies are needed