The application of Friedel Crafts acylation and reduction reactions on the synthesis of organic semiconductors

Organic semiconductors are promising as building blocks for the next generation electronic devices due to their properties such as low cost, flexibility and comparability with plastics. Recently, a large number of tetracene and pentacene derivatives have been synthesized and reported as high performance organic semiconductors. One synthetic pathway towards tetracene derivatives is Friedel Crafts acylation reaction. In this thesis, the synthesis of 6,11-dihydroxy naphthacene-5,12-dione was investigated, and reaction condition was optimized. The experiments show that washing steps have great impact on the quality of the product, and the sequence of adding reactants is crucial to the synthesis. The best solvent for the synthesis is nitrobenzene. In the second part of this thesis the synthesis of some anthracene derivatives was exploited. With sodium dithionate, 1,4-dimethoxyl antracene-9,10-dione can be reduced to the desired product R4(dihydroxyl dimethoxyl anthracene), but 1,4-hydroxy anthracene-9,10-dione is reduced to R2, a tautomer of the expected compound R1. Using NaBH4as the reducing reagent, an unexpected anthracene derivative is obtained, where the two oxygen atoms are removed from the structure and the molecule is fully conjugated

Hepatitis E virus infection in the liver transplant recipients: Clinical presentation and management

Hepatitis E virus (HEV) is an emerging pathogen and an increasingly recognized cause of graft hepatitis, especially in the post-orthotopic liver transplantation immunocompromised population. The exact incidence and prevalence of HEV infection in this population remains unclear but is certainly greater than historical estimates. Identifying acute HEV infection in this population is imperative for choosing the right course of management as it is very difficult to distinguish histologically from acute rejection on liver biopsy. Current suggested approach to manage acute HEV involves modifying immunosuppression, especially discontinuing calcineurin inhibitors which are the preferred immunosuppressive agents post-orthotopic liver transplantation. The addition of ribavirin monotherapy has shown promising success rates in clearing HEV infection and is used commonly in reported cases

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Art magazine featuring the creative work of students, faculty and staff of the Boston University Medical Campus and Boston Medical Cente