Erlotinib hydrochloride: an anticancer agent

In the cation of the title compound, C(22)H(24)N(3)O(4) (+)·Cl(-), an active ingredient of the anti-cancer drug also known as Tarceva, the quinazoline ring system is planar within 0.044 (3) Å. The dihedral angle formed by the mean planes of the two six-membered quinazoline rings is 3.2 (1)°. Both N-bound H atoms participate in N-H⋯Cl bonds, which link the ions into infinite chains running along the b axis. C-H⋯O inter-actions involving neighboring cations provide additional stabilization of these aggregates.