Synthesis of 4-Benzidinyl Butyric Acid: A Key Intermediate for Antibodies Production Against Benzidin

Abstract

a four-step synthesis of monoalkylated benzidin is reported for immunogen preparation against benzidin dye. Use of 10% H₂SO₄/ dioxan for N-Boc cleavage avoids the cyclisation of 4-benzidinyl butyric acid into the corresponding lactam observed with the classical TFA/ CH₂Cl₂ system.

Notes

EC Directive relating quality of water intended for human consumption (80/778/EEC), Off. J. Eur. Commun., L229/11

Data of lactam 5:

¹H NMR (DMSO) δ: 2.08 (quint., J = 7.5 Hz, 2 H, CH₂CH ₂CH₂), 2.5 (CH ₂CO, with DMSO), 3.86 (t, J=6.8 Hz, 2H, CH ₂N), 7 (d, J=8.6 Hz, 2 H_ar), 7.6 (m, H_ar).

MS (IC+NH₃) m/z: 253 [MH⁺].