title: Secohellebrigeninamide.
abstract: The title compound, C(26)H(37)NO(5), was the reaction product of hellebrigenin with N,N-dimethyl-formamide. It consists of three cyclo-hexane rings (A, B and C), one five-membered ring (D) and one dihydro-pyran ring (E). The stereochemistry of the ring junctions is is A/B cis, B/C trans, C/D cis and C/E trans. The cyclo-hexane rings A, B and C have chair conformations. Both the five-membered ring D and the dihydro-pyran ring adopt an envelope conformation. Two orientations are found for the aldehyde group with occupancies of 0.608 (10) and 0.392 (10). In the crystal, short O-H⋯O hydrogen bonds and short C-H⋯O contacts involving the hy-droxy group, terminal methyl group and carbonyl group link the mol-ecules into a three-dimensional network.
authors.affiliation: Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine and New Drugs Research, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632,  People's Republic of China.
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Yuan
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Tian
authors.forename: Jin-Hang
authors.initials: JH
authors.lastname: Li
authors.forename: Tong
authors.initials: T
authors.lastname: Yu
authors.forename: Ren-Wang
authors.initials: RW
authors.lastname: Jiang