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An NMR study of 15‐epiclusianone, 1‐benzoyl‐6‐hydroxy‐14,14‐dimethyl‐3,5,15‐tri(3‐methyl‐2‐butenyl)‐bicyclo[3.3.1]non‐1‐ene‐4,6‐dione (1), a novel tetraisoprenylated benzophenone isolated from pericarp of fruits of Rheedia gardneriana, is described. In addition to conventional 1D NMR techniques, 2D shift‐correlated NMR experiments [1H × 1H‐COSY, 1H × 13C‐HMQC‐1J(C,H), 1H × 13C‐HMBC‐nJ(C,H) (n = 2 and 3) and 1H × 1H‐NOESY] were used for 1H and 13C chemical shift assignments of this natural product. The 1D 13C NMR spectrum of 1 in the solid state was also obtained. Copyright © 2001 John Wiley & Sons, Ltd.

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Three thermotropic phase transitions have been detected in Cs2CdBr4: a second-order orthorhombic to incommensurate transition at T~ = 252 K, a first-order incommensurate to monoclinic transition at T,,~ = 237 K and a second-order monoclinic to triclinic transition at T~2 = 156 K. The incommensurate phase of Cs2CdBr 4 has been studied by single-crystal X-ray diffraction. Main reflections and first-order satellites were measured at 245 K. Based on extinction rules for the diffracted intensities, the superspace group could be determined unambiguously. The modulation vector could be precisely measured as q = 0.170 (3)a*. The incommensurately modulated structure is characterized by a rotation of the CdBr 4 tetrahedra around a in addition to a slight translational component along b. In the monoclinic phase the rotation of the tetrahedra is 'locked' and the structure analysis shows the existence of two twinning domains. Crystal data: dicaesium tetrabromocadmate, Cs2CdBr4, M r = 697.9. At 245 K: ppnma rs s, a = 10.205 (4), b = 7.887 (3), ¢ = 13.925 (7) A, 2(CuKct)= 1.5418 A, R =0.054 for 578 reflections.