Scheme 7.

Synthesis of 4-aminopyrrolo[2,1-f][1,2,4]triazine derivative 39. i) Et₃N, EtOH, 2,4-dimethoxybenzylamine, 120 °C MW; ii) NIS, CH₃CN, RT; iii) CH₂=CHSnBu₃, Pd(t-Bu₃P)₂, CuI, NMP, 120 °C; iv) 9-BBN, THF, 0 °C to RT; then aq. NaBO₃; v) n-BuLi, CF₃SO₂OCH₂P(O)(OiPr)₂, THF, −78 °C; vi) CF₃COOH, CH₂Cl₂, rt; vii) TMSBr, pyridine, rt then (L)-NH₂CH(Bn)COOiPr·HCl, PPh₃, Aldrithiol-2, pyridine, Et₃N, 70 °C.