Crystal structure of 4-{[(naphthalen-2-yl)sulfonyl-amino]-meth-yl}cyclo-hexa-necarb-oxy-lic acid.

The title compound, C18H21NO4S, is a new sulfonamide derivative of tranexamic acid. In the crystal, mol-ecules form inversion dimers via O-H⋯O hydrogen bonds involving the carb-oxy-lic acid groups. Hydrogen bonding between the sulfonamide N-H group and the carb-oxy-lic acid O atom assembles the dimers into thick layers parallel to (100).