Table II.

Backbone dihedral angles of crystalline AcProOMe, 1, 2, 5, and 7 derived from X-ray diffraction analysis ^a

Compound	Ring pucker	ϕ	ψ	ω
AcProOMea	Cγ-endo	−78.9	176.7	−3.1
5	Cγ-endo	−73.9	–170.9	−3.4
1b	Cγ-exo	−62.0	156.4	−180.0
2	Cγ-exo	−58.2	142.0	−179.4
7b	Cγ-exo	−55.4	140.6	−177.0

^aϕ, C_i−1−N_i−C_i^α−C_i; ψ (herein), N_i−C_i^α−C_i−O_i+1; ω, O_i−1−C_i−1−N_i−C_i^α

^bData are from ref 20.