A DSC and FTIR spectroscopic study of the effects of the epimeric coprostan-3-ols and coprostan-3-one on the thermotropic phase behaviour and organization of dipalmitoylphosphatidylcholine bilayer membranes: Comparison with their 5-cholesten analogues.

•Cholesterol-like effects on DPPC bilayers decrease in the order 3β-ol>3α-ol>3-keto.•Polar group variations produce greater effects in the cholesterol than in the coprostanol series.•The cholesterol series is more effective at ordering DPPC bilayers than the coprostanol series.•The lesser effectiveness of the coprostanol series is due to the inverted ring A/B junction.•A double bond located at Δ5 is required for maximum solubility in DPPC bilayers.