One-pot, regiospecific assembly of (E)-benzamidines from δ- and γ-amino acids via an intramolecular aminoquinazolinone rearrangementElectronic supplementary information (ESI) available: General methods, synthetic procedures and characterization for compounds 12a-m, 18a-b, 19a, and 24a-d as well as 1H and 13C NMR for final compounds. See DOI: 10.1039/c5ob02378e

The efficient generation of novel, N -linked benzamidines resulting from a regiospecific rearrangement of quinazolinones is described. This methodology study explored reaction parameters including the effect of changing solvent and temperature, as well as varying electronic substituents on the structural core. The transformation was extensively optimized in terms of reaction conditions and scope, resulting in a protocol that consistently affords diversely functionalized amidines in high yield. The process permits regional structural derivatization that was previously inaccessible, and the multistep process was also reduced to a telescoped, five-step sequence that efficiently affords pharmacologically unique ( E )-benzamidoamidines from N -BOC protected γ- and δ-amino acids. Conversion of extended N -BOC protected amino acids to ( E )-cycloamidines has been accomplished through an efficient, intramolecular rearrangement of aminoalkylquinazolinones.