Syntheses of 1,5-benzothiazepines: Part XVIII-Syntheses of potential, fluorinated 2,4-diaryl-8-ethoxy / fluoro-2,5-dihydro-1,5-benzothiazepines as prospective cardiovascular agents

1181-118

(E)-1-(2,5-Dimethyl-3-thien­yl)-3-(2,4,5-trimeth­oxy­phen­yl)prop-2-en-1-one

In the title compound, C18H20O4S, the thio­phene and benzene rings are oriented at a dihedral angle of 10.83 (11)°. The central chain makes dihedral angles of 1.86 (13) and 9.25 (12)° with the benzene and thio­phene rings, respectively. In the crystal, mol­ecules are linked through weak inter­molecular C—H⋯O inter­actions. π–π inter­actions are also observed between the benzene rings with a centroid–centroid distance of 3.6832 (12) Å. The slippage between the benzene rings is 0.956 Å

Synthesis of a series of 2,3-disubstituted 4H-1,4-benzothiazines and X-ray crystal structure of ethyl 7-chloro-3-methyl-4H-1,4-benzothiazine-2-carboxylate

The reaction between 2-aminobenzenethiol and ethyl acetoacetate is studied under a variety of conditions, and a procedure for the exclusive synthesis of 1,4-benzothiazines by the neat reaction of substituted aminothiols with beta-ketoesters and beta-dicarbonyl compounds in 85-96% yield is described. With microwave heating, even when both the reactants are solid, yields are high, reaction times brief, and work-up easy. A facile reaction is also observed even in a solid-state reaction. The molecular structure of ethyl 7-chloro-3-methyl-4H-1,4-benzothiazine-2-carboxylate (4d) was determined by single-crystal X-ray diffraction