Stabilized carbanions of malonates, 2-phenylacetonitrile, or isopropyl 2-phenylacetate add to m-(trichloromethyl)nitrobenzene derivatives to form σ H adducts that lose a chloride ion to give intermediate exo-dichloromethylene nitrocyclohexadienes. These undergo re-aromatization through 1,5-hydrogen shift to yield tele substitution mono adducts. Depending on the stoichiometry of the nitroarene to the carbanion, further addition of the nucleophile to the tele mono adduct can yield a mixture of products that are either double or triple adducts. At low temperature, the σ H adducts undergo direct 1,2-addition in competition with chloride ion elimination/1,5-hydrogen shift.

Thieno[2,3-d]pyrimidine Amino Acid or Peptide Derivatives Evangelos E. Bissyris,a Dimitris Belekos,b Vassiliki Magafa,a Petros G. Tsoungas,c George Varvounis,*b Paul Cordopatis*a a Department of Pharmacy, University of Patras, Rio 26504, Greece Fax +30(2610)997714; E-mail: pacord@upatras.gr b Department of Chemistry, University of Ioannina, Ioannina 45110, Greece Fax +30(26510)98799; E-mail: gvarvoun@cc.uoi.gr c Ministry of Development, Department of Research and Technology, 14–18 Messogion Ave., Athens 11510, Greece Received 6 June 2005

2-Amino-4-pyrrolidinothieno[2,3-d]pyrimidine-6-carboxylic acid (4) (ATPC) is an unnatural amino acid with promise in applications as a building block for the synthesis of peptidomimetics. ATPC was obtained from both 3a and 3b thienopyrimidines by hydrolysis and hydrogenolysis, respectively. The synthesis of eleven ATPC-amino acids and two ATPC-peptides is described. ATPC is incorporated as N-terminal moiety in solution or solid-phase peptide synthesis using Boc or Fmoc methodology and without protection of the ATPC amino group.