Abstract:The Suzuki reaction of tetrabromothiophene with arylboronic acids provides a regioselective approach to various 5-aryl-2,3,4-tribromothiophenes, symmetrical 2,5-diaryl-3,4-dibromothiophenes, and tetraarylthiophenes. Unsymmetrical 2,5-diaryl-3,4-dibromothiophenes are prepared by Suzuki reaction of 5-aryl-2,3,4-tribromothiophenes. Tetraarylthiophenes containing two different types of aryl groups are obtained by Suzuki reactions of 2,5-diaryl-3,4-dibromothiophenes. During the optimization of the conditions of each individual reaction, the solvent, the catalyst and the temperature play an important role. In several cases, classical conditions [use of tetrakis(triphenylphosphane)palladium(0), PdA C H T U N G T R E N N U N G (PPh 3 ) 4 , as the catalyst] gave excellent yields. The yields of those transformations which failed or proceeded sluggishly could be significantly improved by application of a new biarylmonophosphine ligand developed by Buchwald and co-workers. Regioselective metal-halide exchange reactions of tetrabromothiophene provide a convenient approach to various 2,5-disubstituted 3,4-dibromothiophenes. 5-Alkyl-2-trimethylsilyl-3,4-dibromothiophenes could be prepared in one pot by sequential addition of trimethylchlorosilane and alkyl bromides. The reaction of tetrabromothiophene with methyl chloroformate and subsequent Suzuki reactions afforded 3,4-diaryl-2,5-bis(methoxycarbonyl)thiophenes.

Regioselective Suzuki cross-coupling reactions of tetrabromoselenophene allow a convenient synthesis of aryl-substituted selenophenes. High yields were obtained using a novel biarylmonophosphine ligand. The first tetra(1-alkynyl)selenophene was prepared in one step by a Sonogashira reaction of tetrabromoselenophene.

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The aim of this study was to present primary outcomes of autologous bone marrow mononuclear cell (BMMNC) transplantation to improve neurological sequelae in four children with intracranial hemorrhage (ICH) incidence during the neonatal period. Methods: GMFM88 and modified Ashworth score were used to assess motor function and muscle spasticity before BMMNC transplantation and after transplantation. Brain MRI was performed to evaluate brain morphology before and after BMMNC transplantation. Bone marrow were harvested from anterior iliac crest puncture and BMMNCs were isolated using Ficoll gradient centrifugation. The microbiological testing, cell counting, and hematopoietic stem cell (hHSC CD34+ cell) analysis were performed, following which BMMNCs were infused intrathecally. Results: Improvement in motor function was observed in all patients after transplantation. In addition, muscle spasticity was reduced in all four patients. Conclusion: Autologous BMMNC transplantation may improve motor function and reduce muscle spasticity in children with ICH incidence during the neonatal period.

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