There are two isomers, 3-T-TRIS and 4-T-TRIS, each similar in structure to trisescaline with a sulfur atom in a place of a different oxygen atom.
The presence of two isomers, 3-T-TRIS and 4-T-TRIS, indicates that the compound's structure can be modified by replacing an oxygen atom with a sulfur atom at different locations, similar to trisescaline.