title: Crystal structure of (3S)-3-acet-oxy-17-(pyridin-3-yl)androsta-5,16-diene.
abstract: In the title compound, C26H33NO2 [systematic name: (3S,8R,9S,10R,13S,14S)-10,13-dimethyl-17-(pyridin-3-yl)-2,3,4,7,8,9,10,11,12,13,14,15-dodeca-hydro-1H-cyclo-penta-[a]phenanthren-3-yl acetate], the steroid A, B, C and D rings adopt chair, half-chair, chair and envelope conformations, respectively. The flap atom of the envelope is the methine C atom fused with the C ring. In the crystal, adjacent mol-ecules, generated by a 21 screw axis, are linked by weak C-H⋯O hydrogen bonds, forming a C(16) helical chain running along the c-axis direction.
authors.affiliation: Hangzhou Jiuyuan Gene Engineering Co. Ltd, Hangzhou 310018, Zhejiang, People's Republic of China.
authors.forename: Shengjun
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Department of Chemistry, Xiamen University, Xiamen 361005, People's Republic of China.
authors.forename: Huaqi
authors.initials: H
authors.lastname: Huang
authors.affiliation: Department of Chemistry, Xiamen University, Xiamen 361005, People's Republic of China.
authors.forename: Rongbin
authors.initials: R
authors.lastname: Huang
keywords: C(16) chain; androsta-5,16-diene; crystal structure; hydrogen bonds
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