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Cholesteryl pentanoate (C32O2H54) is orthorhombic, space group P212121, with a = 21.930(3), b = 21.404(3), c = 6.419(5) Å, Z = 4, V = 3012.8(5)Å3, Dc = 1.04 gcm-3, λ(Mo Kα) = 0.71069 Å, μ = 0.58 cm-1, F(000) = 1048, T = 298, R = 0.086 for 1502 unique observed reflections with I > 1.0 σ (I). The structure was solved by direct methods and refined by cascade diagonal least-squares refinement. The C-H bond lengths and the methyl groups are fixed and refined as their ideal geometry. A comparison with other cholesteryl esters gives normal structure for the tetracyclic ring, while the tail regions of the side chain and the ester group which stands on end, show a variation from their normal values, presumably due to thermal effects. The molecules are stacked together by non-bonded van der Waals forces with the shortest intermolecular distance of 3.529 Å.
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