Stereoselective protecting-group-free synthesis of alkyl glycosides using dibenzyloxy triazine type glycosyl donors.

Chemical O-glycosylation is a key step for the synthesis of sugar-containing molecules such as glycolipids. However, traditional carbohydrate chemistry is characterized by extensive use of protective groups, resulting in laborious manipulations and poor atom economy. Here, we present a protecting-group-free glycosylation strategy employing dibenzyloxy-1,3,5-triazin-2-yl glycosides (DBT-glycosides) as glycosyl donors. The DBT-glycosyl donors could be prepared directly through an alkaline nucleophilic substitution from unprotected sugars in aqueous media. The O-glycosylation of alcohols by using DBT-glycosyl donors has been carried out under mild hydrogenolytic conditions, affording the corresponding alkyl glycosides stereo-selectively in good yields.

A Convolutional Neural Network-enabled IoT framework to verify COVID-19 hygiene conditions and authorize access to facilities.

COVID-19 has infected several million of individuals while claiming numerous lives. This fact raised the need to apply the measure to prevent its transmission. The use of disinfection products, wearing masks, and avoiding touching doors are important measures to avoid its spread. Thus, this work proposes a framework supported by a Convolutional Neural Network (CNN) model checking the hygienic conditions of the individuals requiring authorization to access facilities. The experimental work takes IoT devices with sensors to check: whether the users have disinfection product in their hands and a trained model to check whether individuals are also wearing masks. The achieved results highlighted the effectiveness of the proposed framework.

Multiple esophageal ulcers due to tofacitinib 10 mg twice daily for ulcerative colitis.

A 26-year-old man was admitted to our institution for ulcerative colitis treatment. He used mesalamine, steroid, immunomodulators, and anti-TNFα anti-body, but it was difficult to maintain remission. We started induction therapy with tofacitinib (TOF) 10 mg twice daily. He maintained clinical remission but had chest pain 44 days after the start of TOF. Esophagogastroduodenoscopy showed multiple ulcers from middle to lower esophagus. Although rare, TOF induced esophageal ulcers were considered based on his clinical course and endoscopic findings.