The object of the present invention is benzothiazine derivatives having the capability of inhibiting 11ß-HSD1 not only at an enzymatic level but also at a cell level. The compounds of the present invention are of general formula (I). Wherein notably R1 represents a hydrogen or OR1 represents an ester or an ether. R2 represents a naphthyl or a 1, 2, 3, 4-tetrahydro-naphthalene or a biphenyl or phenyl pyridine or a substituted phenyl. R3 represents a methyl or ethyl R4 and R4 represent a hydrogen.