Ozonide (II): 3,4aβ,5,7,8,8a-hexahydro-3,3-dimethyl-7β,8aβ-diphenyl-5α, 7α-epidioxypyrano[ 3,4-e ]-[1,2,4]trioxine, C₂₀H₂₀O₆, m.p. 406-408K, M_r = 356.4, triclinic, P1, α = 5.634(1), b = 10.079(3), c = 16.785 (3)Å, α = 104.48 (4), β = 93.48 (3), γ = 103.93(1)°, V= 888.3 (4) ų, Z = 2, D_x = 1.33 Mg m^-3, λ(Mo Kα) = 0.7107 Å, μ = 0.092mm^-1, F(000) = 376, room temperature, R = 0.069 for 1022 observed reflections [|F_o| ≥ 3σ(F_o) and |F_o| ≥ 4.0]. Spirocyclic acetal (III): 3,4aβ,5,7,-8,8a-hexahydro-3,3-dimethyl-7α-phenyl-7,8a-(epoxy-o-benzeno)pyrano[3,4-e] [ 1,2,4]trioxin-5α-ol, C₂₀H₂₀O₆, m.p. 408-416K, M_r=356.4, monoclinic, C2/c, α =30.962(4), b = 6.126(1), c = 18.862(3)Å, β = 104.52 (1)°, V = 3463.3 (9) ų, Z = 8, D_x = 1.37 Mg m^-3, λ(Mo Kα) = 0.7107 Å, μ = 0.094 mm^-1, F(000) = 1504, room temperature, R = 0.066 for 1163 observed reflections [|F_o| ≥ 3σ(F_o) and |F_o| ≥ 8.0]. Hydroperoxide (V): cis-3,4a,5,7a-tetrahydro-6,7adiphenylcyclopenta[1,2-e][1,2,4]trioxin-5β-yl hydroperoxide, C₁₈H₁₆O₅, m.p. 401-403 K, M_r= 312.3, monoclinic, P2₁/c, α = 8.9185(12), b = 22.595 (3), c = 8.0069(12) Å, β = 111.01 (2)° , V = 1506.2 (4) ų, Z = 4, D_x = 1.38 Mg m^-3, λ(Mo Kα) = 0.7107 Å, μ = 0.094 mm^-1, F(000) = 656, room temperature, R = 0.038 for 1047 observed reflections [|F_o| ≥ 3σ(F_o) and |F_o| ≥ 7.0]. All three molecules possess 1,2,4-trioxane rings which adopt chair conformations and are cis fused to the adjacent ring. Hydrogen bonds occur in the molecular packing of compound (V). No especially short interatomic contacts were observed for (II) and (III).