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Updated: Jun 22, 2026

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
D-ring-opened phragmalin-type limonoid orthoesters from the twigs of Swietenia macrophylla
Bing-Dong Lin1, Chuan-Rui Zhang, Sheng-Ping Yang
1Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, People's Republic of China.
Abstract:
Sixteen new D-ring-opened phragmalin limonoid orthoesters, swietenitins A-M (1-6, 8, 10, 12-16), 2-acetoxyswietenialide D (7), 2,11-diacetoxyswietenialide D (9), and 11-deoxyswietenialide D (11), and four known compounds were isolated from the twigs of Swietenia macrophylla. The structures of 1-16 were established on the basis of spectroscopic methods, and 1 and 2 were confirmed by single-crystal X-ray diffraction. The (1)H NMR-based conformational analysis on the epimeric compounds 1 and 2 provided a general approach to determine the absolute configuration of the 2,3-epoxy-2-methylbutyryloxy unit at C-3 borne by a large group of the known phragmalin-type limonoid orthoesters.
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