M. Chelli et al., CYCLIZATION OF C-TERMINAL HISTIDINE PEPTIDES TO 7-AMINO-DIHYDROIMIDAZO[1,5-C]PYRIMIDIN-5-ONE DERIVATIVES, Journal of chemical research. Synopses, (3), 1993, pp. 118-119
N-Substituted 7-amino-dihydroimidazo[1,5-c]pyrimidin-5-ones were obtai
ned by cyclization of C-terminal histidine peptides at room temperatur
e via a Curtius rearrangement.