Ethyl N-phenyloxamate.

The oxamate group in the title compound, C(10)H(11)NO(3), is almost coplanar with the phenyl ring because of intramolecular hydrogen-bonding interactions, and the structure can be described as an anilide single bonded to an ethyl carboxylate group. The supramolecular structure is achieved through intermolecular hard N-H...O and soft C-H...X (X = O and phenyl) hydrogen-bonding interactions.

2-Amino-1,3-benzothiazole-ethyl coumarin-3-carboxylate (1/1).

The title adduct, C(7)H(6)N(2)S.C(12)H(10)O(4), is formed via N-H.O and N-H.N hydrogen-bonding interactions, which generate a tetrameric unit with a pseudo-centre of symmetry. The tetramer further packs through parallel-displaced pi-pi stacking interactions along the a direction.