Table 1. Selected torsion angles (°).

C20A—C9A—C10A—C11A	159.65 (17)
C20A—C9A—C10A—C15A	−21.5 (3)
C20B—C9B—C10B—C11B	−140.01 (18)
C20B—C9B—C10B—C15B	43.2 (2)