In crystal structure of the title compound, C12H21N3O5S3 [systematic name: (R)-4-ethyl-amino-2-(3-meth-oxy-prop-yl)-3,4-di-hydro-2H-thieno[3,2-e][1,2]thia-zine-6-sulfonamide 1,1-dioxide], there exist three kinds of hydrogen-bonding inter-actions. The sulfonamide group is involved in hydrogen bonding with the secondary amine and the meth-oxy O atom, resulting in the formation of layers parallel to the bc plane. The layers are linked by an N-H⋯O hydrogen bond involving a sulfonamide O atom as acceptor and the secondary amine H atom as donor, which gives rise to the formation of a unique bilayer structure. The absolute structure of the mol-ecule in the crystal was determined by resonant scattering [Flack parameter = 0.01 (4)].
Keywords: Brinzolamide; absolute configuration; carbonic anhydrase inhibitor; crystal structure; hydrogen bonding; sulfonamide; thiazine.