Received 24 January 2013
In the title compound, C20H19NO4, the absolute configuration (3R,4S) for the two chiral centres of the molecule has been determined.
Data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2010); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: MW2104 ).
The work was supported financially by the National Natural Science Foundation of China (No. 81172920), the Shanghai Municipal Committee of Science and Technology (No. 10431903100) and the National Basic Research Program of China (973 Program, No. 2010CB912603). We would like to thank Dr Jie Sun for the single-crystal X-ray determination.
Bruker (2010). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.
Flack, H. D. (1983). Acta Cryst. A39, 876-881.
Ganesh, T., Yang, C., Norris, A., Glass, T., Bane, S., Ravindra, R., Banerjee, A., Metaferia, B., Thomas, S. L. & Giannakakou, P. (2007). J. Med. Chem. 50, 713-725.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.