RESUMO
The methodology to prepare 3-substituted 1,5-dibromopentanes I and their immediate precursors, which include 3-substituted 1,5-pentanediols VII or 4-substituted tetrahydropyrans VIII, is surveyed. Such dibromides I are important intermediates in the preparation of liquid crystalline derivatives containing 6-membered heterocyclic rings. Four dibromides 1a-1d containing simple alkyl and more complex fragments at the 3-position were prepared. 3-Propyl- and 3-pentyl-pentane-1,5-diol (2a,b) were prepared starting from either glutaconate or malonate diesters, while tetrahydropyrans 3c and 3d were obtained from tetrahydro-4H-pyran-4-one. The advantages and disadvantages of each route are discussed. Dibromides 1c and 1d were used to prepare sulfonium zwitterions 11c and 11d.
RESUMO
Epstein-Barr virus (EBV) is a member of the herpesvirus family that is associated with various disease manifestations, including EBV-associated colitis. There are few case reports describing hemorrhage associated with EBV colitis. We report a 61-year-old woman with acute gastrointestinal bleeding due to EBV colitis after initiation of methylprednisolone and enoxaparin for spinal cord infarction. To our knowledge, there are only a few case reports of hemorrhagic EBV colitis. Perhaps we need to have a higher suspicion for EBV in cases of colitis associated with hemorrhage even in relatively immunocompetent patients.