title: Traceless liquid phase synthesis of piperazinediones.
abstract: Liquid phase combinatorial synthesis (LPCS) of piperazinediones by the use of soluble polymer support is explored to generate libraries. Proline anchored polyethylene glycol monomethyl ether (PEG) underwent dipeptide formation with different Fmoc-amino acids in the presence of dicyclohexyl carbodiimide (DCC). Deprotection of Fmoc accompanied with the cleavage from polymer support with cyclization of dipeptide to piperazinediones offers a facile and effective way to prepare diverse combinatorial libraries. Excellent yields and purities were achieved by simple wash and precipitation method.
authors.affiliation: Department of Chemistry, National Dong Hwa University, Shou-Feng, Hualien 974, Taiwan. cmsun@mail.ndhu.edu.tw
authors.forename: Chung-Ming
authors.initials: CM
authors.lastname: Sun
authors.forename: K M K
authors.initials: KM
authors.lastname: Swamy
authors.forename: Mei-Jung
authors.initials: MJ
authors.lastname: Lin
authors.forename: Wen-Ben
authors.initials: WB
authors.lastname: Yeh
authors.forename: Fred Y
authors.initials: FY
authors.lastname: Chen
authors.forename: Wei-Hong
authors.initials: WH
authors.lastname: Tseng
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D020650:Combinatorial Chemistry Techniques; D003500:Cyclization; D004024:Dicyclohexylcarbodiimide; D004151:Dipeptides / Q000138:chemical synthesis; D005449:Fluorenes / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D010879:Piperazines / Q000138:chemical synthesis*; D011092:Polyethylene Glycols
chemical_list: D000596:Amino Acids; D004151:Dipeptides; D005449:Fluorenes; D007202:Indicators and Reagents; C016456:N(alpha)-fluorenylmethyloxycarbonylamino acids; D010879:Piperazines; D011092:Polyethylene Glycols; D004024:Dicyclohexylcarbodiimide