Zirconium-catalyzed one-pot synthesis of benzoxazoles using reaction of catechols, aldehydes and ammonium acetate.

In this study, an efficient method for the synthesis of benzoxazoles by coupling catechols, aldehydes and ammonium acetate using ZrCl as catalyst in ethanol is reported. A wide range of benzoxazoles (59 examples) are smoothly produced in high yields (up to 97%). Other advantages of the method include large-scale synthesis and the use of oxygen as an oxidant.

MDS-Type Morphologic Abnormalities of Peripheral Blood Granulocytes in Symptomatic COVID-19 Patients.

Hematological abnormalities in COVID-19 infection included quantitative and qualitative changes and should be further characterized. Evaluation for myelodysplastic syndromes (MDS) is usually prompted by abnormal hematologic findings and the presence of dysplastic morphologies. Viral infections are considered to be the cause of dysplastic morphologies and should be considered by morphologists.

Rhodium-Catalyzed Asymmetric Macrocyclization towards Crown Ethers Using Hydroamination of Bis(allenes).

Enantiomerically enriched crown ethers (CE) exhibit strong asymmetric induction in phase transfer catalysis, supramolecular catalysis and molecular recognition processes. Traditional methods have often been used to access these valuable compounds, which limit their diversity and consequently their applicability. Herein, a practical catalytic method is described for the gram scale synthesis of a class of chiral CEs (aza-crown ethers; ACEs) using Rh-catalyzed hydroamination of bis(allenes) with diamines.

Management of oxidative stress for cell therapy through combinational approaches of stem cells, antioxidants, and photobiomodulation.

Over the recent decades, stem cell-based therapies have been considered as a beneficial approach for the treatment of various diseases. In these types of therapies, the stem cells and their products are used as treating agents. Despite the helpful efficacy of stem cell-based therapies, there may be challenges.

Rhodium-Catalyzed Allylic Addition as an Atom-Efficient Approach in Total Synthesis.

ConspectusFinding efficient synthetic methods for the asymmetric synthesis of complex molecules has always been of interest to organic chemists. Creating and controlling the stereochemistry of stereogenic centers bearing branched allylic moieties in organic molecules using a catalytic process is an attractive and successful method for the synthesis of several natural products and medicinally important compounds. Remarkable progress toward their synthesis has been achieved via transition-metal catalysis, especially in the case of allylic substitution and allylic C-H oxidation chemistry.