Abstract
The asymmetric unit of the title compound, C
10
H
13
NO
4
S, comprises two crystallographically independent molecules. The crystal structure is stabilized by weak intermolecular C—H⋯O hydrogen bonds, which link molecules along the
b
axis. The crystal is a nonmerohedral twin, the refined ratio of the twin components being 0.344 (2):0.656 (2).