“…In a similar manner, the flatten- 17, 111.77° (19), 110.20° (17) and 118.94° 17, respectively. Maximum torsion angle of 73.3°(Φ 8,9,11,12 ) supported the distorted chair of ring C [27]. Furthermore, the corresponding endocyclic torsion angle measurements (ΔC s 9,13 = |Φ 8,9 + Φ 9,11 | + |Φ 8,14 + Φ 11,12 | + |Φ 13,14 + Φ 12,13 | = 12°) [26] suggested that the approximate plane of symmetry of the flattened chair form of C passed through C(9) and C (13).…”