Corrections to Nomenclature of Phosphorus-Containing Compounds of Biochemical Importance

Crystals of cholesteryl oleate (C₄₅H₇₈O₂) are monoclinic, space group P2₁, with $\text{a = 12.65(3), b = 9.13(3), c = 18.79(5)}\text{A}\text{?}\text{, β = 93.3(3)°}$ and have 2 molecules in the unit cell. The crystal structure has been determined by Patterson and Fourier methods at a resolution $\text{d}{}_{\mathrm{<mtext>min</mtext>}}\text{= 1.1}\text{A}\text{?}$, using 799 X-ray intensities (CuKα) measured by a diffractometer. Structure refinement by block-diagonal least squares gave R = 0.12. The oleate chains are almost straight except for a kink at the cis-double bond. The chains pack side by side but without a regular sub-cell structure, in a manner which might be similar to the arrangement within biological membranes. As in cholesteryl octanoate, the cholesteryl ring systems pack together with extensive overlap of anti-parallel nearest neighbours. Projecting methyl groups interlock.